Whole Brain Atlas (med.harvard.edu)
Brain Cells More Powerful Than You Think (healthfinder.gov 19.12.2007)
The Human Brain and Muscular System (academicearth.org)
In animals, they said, brain damage prompts the birth of new cells. "Our study provides the foundation for this possibility in the adult human brain," they wrote in their report, published in the journal Science. (reuters.com 16.2.2007)
Carlsen blir hyllet som «sjakkens Mozart» i USA (CBS) (dagbladet.no 20.2.2012)
Når hjernen misser grepet (uib.no 13.11.2007)
Appelsinens hemmelighet (aftenposten.no 20.6.2008)
- Det siste vi har på plass, er det vi trenger mest (aftenposten.no 21.2.2008)
Brain Turns to Positive Thoughts When Faced With Death
(healthfinder.gov 28.12.2007)
Protein avgjør hvor godt du takler motgang (vg.no 25.10.2007)
Avhengig? Hjernen har svaret (aftenposten.no 3.1.2008)
Blir ruset av sukker (aftenposten.no 10.11.2009)
Verdensledende hjerneforskning i 70 år (apollon.uio.no 8.1.2008)
Ständig smärta stör hjärnans återhämtning (lakemedelsvarlden.se 19.2.2008)
Kan hindre hjernen i å gjøre feil (vg.no 22.4.2008)
- Studie viser at hjernen kan produsere nye celler
Ny stamcell funnen i hjärnan
cisionwire.se 18.4.2012
Forskare vid Lunds universitet har hittat en ny stamcell i den vuxna hjärnan. Resultaten visar att dessa celler kan föröka sig och bilda flera olika celltyper. Viktigast av allt, de kan bilda nya hjärnceller. Nu hoppas forskarna kunna dra nytta av fyndet för att utveckla metoder som kan reparera sjukdomar och skador i hjärnan.
Den nyupptäckta cellen sitter kring små blodkärl i hjärnan. En liknande celltyp har tidigare identifierats i flera andra organ där ger den upphov till återuppbyggnad av muskler, ben, brosk och fettväv. Genom att analysera hjärnvävnad från biopsier och hjärnsnitt har forskarna nu för första gången påträffat stamcellen hjärnan. Vilken specifik funktion cellen har i hjärnan är ännu oklart men dess rörliga egenskaper tyder på stor potential.
- Våra fynd har efterhand visar att cellernas kapacitet är mycket större än vi först trodde. Dessa celler är väldigt mångsidiga. Mest intressant är att de har förmågan att bilda nervceller, men de kan även utvecklas till andra celltyper. Våra resultat bidrar nu med ökad förståelse för hur hjärncellernas plasticitet fungerar och öppnar upp nya möjligheter att utnyttja precis dessa egenskaper, säger Gesine Paul-Visse, en av studiens författare.
I andra organ har det funnits tydliga tecken på att just dessa celler medverkar till reparation och sårläkning. Forskarna tror att de botande egenskaperna kan gälla även för hjärnan. Nästa steg blir att försöka kontrollera och förstärka stamcellernas självläkande egenskaper med målsättningen att utföra riktade terapier mot ett specifikt område i hjärnan.
- Vi hoppas att vårt fynd kan leda till en ny och bättre förståelse av hjärnans egna reparationsmekanismer. I förlängningen är målsättningen att förstärka dessa mekanismer och ta fram nya behandlingar som kan reparera den sjuka hjärnan, säger Gesine Paul-Visse.
Resultaten i rapporten, som publiceras i tidskriften PLoS ONE, är av intresse för brett spektra inom hjärnforskningen. Framtida möjliga terapeutiska måltavlor sträcker sig från neurodegenerativa folksjukdomar till stroke. (...)
Voksen hjerne kan vokse raskt
nrk.no 8.4.2011
Hjernen din kan bli større når du lærer på samme måte som barn. Ny grå materie ble dannet etter bare to timer med språklæring hos forsøkspersoner.
Hos spedbarn vokser og utvikler hjernen seg raskt. Nervecellene i hjernen blir både flere, mer spesialiserte og danner flere koblinger med hverandre.
Den voksende hjernen er plastisk, den har evnen til å endre seg under påvirkning av forholdene som omgir den.
Til nå har forskerne trodd at hjernen hos voksne ikke endrer seg noe særlig, og har mistet sin plastisitet. (...)
Ny motorväg för stamceller identifierad i den mänskliga hjärnan
sahlgrenska.gu.se 16.2.2007
Ett unikt forskningssamarbete har lett till upptäckten av en ny anatomisk struktur för transport av stamceller i människans hjärna. Den nyupptäckta strukturen tros ha betydelse vid skada eller sjukdom i hjärnan. (...)
Human brain can make new cells, study finds (Studie viser at menneskelig hjerne kan produsere nye celler)
By Maggie Fox, Health and Science Editor
reuters.com 16.2.2007
WASHINGTON (Reuters) - New evidence shows that the human brain can manufacture fresh brain cells, researchers said on Thursday in a study that may lead to better ways to treat brain damage and disease.
Scientists had known that other animals, such as rats and mice, make new brain cells throughout their lives and there had been indirect evidence that humans being can, too.
Using magnetic resonance imaging, or MRI, scans and electron microscope images of tissue donated from the brains of people who died, Maurice Curtis of the University of Auckland in New Zealand and Peter Eriksson of Sahlgrenska Academy in Goteborg, Sweden, and colleagues found the elusive cells.
Just as in mice and rats, these cells are born in one part of the brain and then migrate to the olfactory bulb, where smells are processed. They mature into neurons on the way.
In animals, they said, brain damage prompts the birth of new cells. "Our study provides the foundation for this possibility in the adult human brain," they wrote in their report, published in the journal Science.
Humans have far more developed brains, so searching for these cells has been harder than it was in rodents.
In mice and rats it has been clear these cells are born in the forebrain and then migrate to the smell center. There, they can help the animals learn and adapt to new smells.
Smell is less important for humans, but it is still important for sensing dangers from smoke, for instance, or rotten food.
And studies show that the loss of smell may be an early sign of brain-destroying illnesses such as Parkinson's, the researchers said -- a hint that these cells may be important.
"This study is exciting because it reveals a group of brain cells in the adult human brain that are continuously regenerating," said Dr. Mark Baxter of Britain's Oxford University.
"Animal studies have pointed to the existence of such groups of cells, but it has been difficult to determine whether they exist in the human brain as well," Baxter, who was not involved in the research, said in a statement.
"This opens another direction by which we may discover ways to repair human brains that are damaged from injury or diseases, and underscores the importance of animal research in guiding biomedical research in humans," Baxter said.
Another expert, Sebastian Brandner, head of the Division of Neuropathology at the Institute of Neurology at University College London, agreed.
"These findings are important for several reasons: Understanding stem cell biology is essential to study brain repair in neurodegenerative diseases such as Alzheimer's and it is even possible that stem cells are the source of some brain tumors," Brandner said in a statement. (...)
(Anm: Science. Published Online February 15, 2007.)
- Hvordan hjerner kommer seg etter fysisk skade
How Brains Bounce Back from Physical Damage (- Hvordan hjerner kommer seg etter fysisk skade)
sciencedaily.com 20.5.2011
After a traumatic injury, neurons that govern memory can regenerate
For most of the past century the scientific consensus held that the adult human brain did not produce any new neurons. Researchers overturned that theory in the 1990s, but what role new neurons played in the adult human brain remained a mystery. Recent work now suggests that one role may be to help the brain recover from traumatic brain injury.
Cory Blaiss, then at the University of Texas Southwestern Medical Center, and her colleagues genetically engineered mice such that the researchers could selectively turn neurogenesis on or off in a brain region called the hippocampus, a ribbon of tissue located under the neocortex that is important for learning and memory. (...)
The finding may lead to much needed therapeutic techniques. Deficits in learning and memory are nearly universal after a traumatic brain injury. The ability to stimulate more robust neurogenesis could lead to faster healing times or perhaps even more complete recovery of cognitive functions, a potentially life-changing prospect for the millions of people who suffer from traumatic brain injury every year. (...)
- Hvor mye kan hjernen restituere seg etter år med overdreven alkoholinntak
How much can the brain recover from years of excessive alcohol consumption? (Hvor mye kan hjernen restituere seg etter år med overdreven alkoholinntak)
scientificamerican.com 8.10.2011
Richard Ridderinkhof, professor of neurocognitive development and aging at the University of Amsterdam, answers
Evidence shows that heavy alcohol use modifies the structure and physiology of the brain, although the extent of recovery after years of abstinence is unclear.
Recent neuroimaging studies have revealed that chronic alcoholism can damage the cerebellum, which plays an important role in regulating motor control, attention and language. It can also cause the prefrontal cortex to shrink and degrade, potentially impairing decision-making skills and social behavior. Studies have also found damage in the white matter of the brain, which connects these regions.
The question remains, however, whether such extensive damage can be reversed after abstaining from alcohol. Researchers have studied the effects of abstinence on the brains of alcohol-dependent individuals by comparing subjects recovering from years of alcohol abuse with those who do not drink or drink minimally. Scientists have also investigated changes in brain volume in initial versus sustained abstinence in one set of subjects.
Several of these studies have shown that years of abstaining from booze can allow brain regions to return to their original volume and can repair neural connections across different regions. Much of this restoration occurs in the system most adversely affected by chronic alcoholism—the frontocerebellar circuitry, which regulates decision making, reasoning and problem solving.
Other reports, however, have found sustained injury in certain areas. Some former alcohol abusers show permanent damage to the hippocampus, a brain region that regulates long-term memory and spatial navigation, and only partial resolution of lesions on the white matter.
Although the effects of abstinence on the alcohol-abused brain vary, it appears that we display at least some ability to recover from the effects of excessive drinking. Future neuroimaging studies should clarify the full extent and potential for recuperation.
(...)
- Antipsykotika og hjernevolum (Trenger vi å være bekymret?)
Antipsychotic Medications and Brain Volume (Antipsykotika og hjernevolum)
Arch Gen Psychiatry. 2011;68(2):126-127 (February)
Do We Have Cause for Concern? (Trenger vi å være bekymret?)
Since the initiation of antipsychotic drug therapy for schizophrenia, clinical observations and empirical studies have demonstrated that these medications bring benefit and harm. Consequently, efforts to develop new antipsychotic medications during the past 50 years have been motivated, at least partly, by the desire to enhance the benefit to harm ratio relative to existing medications. In this issue of the Archives, Ho and colleagues1 examine one arm of this ratio by asking whether antipsychotic medications contribute to progressive brain volume reductions in schizophrenia. Individuals early in the course of schizophrenia (n = 211) were treated with antipsychotic medications according to standard clinical practice and followed up longitudinally with clinical assessments and serial magnetic resonance imaging (MRI) scans (between 2 and 5 scans per individual) for a mean of 7 years. The authors found that the amount of exposure to antipsychotic medication predicted decrements in cerebral gray and white matter volumes and increased the volume of the putamen. Illness duration and severity were also associated with smaller brain volume measures, but the relationship between antipsychotic medication use and brain volume remained significant after accounting for the effects of illness severity and duration and substance abuse history. Interestingly, changes in brain volume with time were similar for all classes of antipsychotic medications (ie, typical antipsychotics, atypical [ie, excluding clozapine] antipsychotics, and clozapine). (...)
(Anm: Antipsykotika (psykofarmaka etc.) (mintankesmie.no).)
Antipsychotics May Shrink Brain Volume (Antipsykotika kan krympe hjernevolumet)
medpagetoday.com 8 .2.2011
A long-term imaging study suggests that brain volume in patients with schizophrenia progressively declined with increasing duration of antipsychotic therapy.
The study, conducted among more than 200 patients, found that during an average follow-up of 7.2 years, brain-tissue volumes decreased -- and more intense antipsychotic therapy was associated with generalized and specific reductions in brain tissue, according to Beng-Choon Ho, MD, of the University of Iowa in Iowa City, and colleagues.
Progressive loss of both gray matter and white matter was associated with increasing time on antipsychotics, the investigators reported in the February issue of the Archives of General Psychiatry. However, sulcal cerebrospinal fluid volumes increased with longer follow-up, they added.
"Viewed together with data from animal studies, our study suggests that antipsychotics have a subtle but measurable influence on brain tissue loss over time, suggesting the importance of careful risk-benefit review of dosage and duration of treatment as well as their off-label use," Ho's group wrote in conclusion. (...)
- Studie finner link mellom hjertesvikt og hjerneforandringer
Study Finds Link Between Heart Failure, Brain Changes (Studie finner link mellom hjertesvikt og hjerneforandringer)
health.yahoo.com 1.2.2012
WEDNESDAY, Feb. 1 (HealthDay News) -- Heart failure is associated with a loss of gray matter in the brain and a decline in mental processes, according to a new study.
These changes can make it more difficult for heart failure patients to remember and perform health care instructions such as taking the correct medications at the right times, the Australian researchers said.
They conducted memory and other mental performance tests on 35 heart failure patients, 56 patients with ischemic heart disease (which sometimes but not always accompanies heart failure), and 64 healthy people. MRI exams were used to assess gray matter volume in different parts of the brain.
In heart failure, the heart muscle is unable to pump enough oxygen-rich blood to the body, while ischemic heart disease affects the supply of blood to the heart.
Heart failure patients had worse immediate and long-term memory and reaction speeds than healthy people. The brain scans showed that heart failure was associated with losses of gray matter in areas believed to be important for memory, reasoning and planning.
The study appears online Feb. 1 in the European Heart Journal. (...)
(Anm: Antidepressiva (SSRI-selvmord) (mintankesmie.no).)
- Antidepressiva linket til forverring av hvit substans hos eldre
Antidepressant linked to worsening white matter in elderly (Antidepressiva linket til forverring av hvit substans hos eldre)
rehabpub.com/reuters_article.asp 17.3.2008
NEW YORK (Reuters Health) - The results of a study employing serial cranial MRI suggest that elderly adults who use tricyclic antidepressants may be at increased risk for progression of white matter lesions, which have been linked with late-life depression by previous studies. (...)
The use of an antidepressant from any class during the study period hastened the progression of white matter disease, according to the report in the March issue of Stroke.
Contrary to what the investigators had hypothesized, SSRI use did not reduce, but slightly increased the risk of worsening white matter on multivariate analysis. Still, the 36% increased risk seen with these agents was not statistically significant.
The use of a tricyclic antidepressant, however, was associated with a significantly elevated risk of worsening white matter lesions. Compared with those who used no antidepressants, patients receiving an agent in this drug class had an increased risk of 77%. (...)
(Anm: hvit substans; hvit substans, margkledde nervefibrer, utløpere fra nervecellene i hjerne og ryggmarg. Den hvite fargen skyldes myelin, et fettholdig stoff som danner margskjeder omkring nervefibrene. Kilde: Store norske leksikon.)
(Anm: white matter (hvit substans); Multiple Sclerosis (MS) is one of the most common disease which affects white matter (wikipedia.org).)
Selective serotonin reuptake inhibitor use associates with apathy among depressed elderly: a case-control study (Bruk av selektive serotoninreopptakshemmere er assosiert med apati blant deprimerte eldre: en case-control studie)
Annals of General Psychiatry 2007, 6:7
Background (Bakgrunn)
Det er det siste ti år rapportert at bruk av selektive serotoninreopptakshemmere (SSRI-er) kan være assosiert med forekomst av apati. (...) (It has been reported for over the past decade that the use of selective serotonin reuptake inhibitors (SSRI's) may associate with the emergence of apathy.)
Conclusion (Konklusjon)
Selv om depresjon ble bedre hos eldre pasienter som fikk antidepressiva, opptrådte apati oftere hos pasienter som ble behandlet med SSRI enn hos pasienter som ikke ble behandlet. Dysfunksjon i frontal lobe på grunn av serotonerge endringer er ansett som en av mulighetene. (...) (Even though depression was improved in elderly patients receiving antidepressants, apathy appeared to be greater in patients who were treated with SSRI than that found in patients who were not. Frontal lobe dysfunction due to alteration of serotonin is considered to be one of the possibilities.)
(Anm: apati (av gr. nektende a og 'affekt'), psykologisk og psykiatrisk begrep som betyr mangel på sjelelige følelser (affekter). Som regel ledsaget av interesseløshet. Sees særlig ved svære depressive og schizofrene tilstander.
(Anm: pannelappen; lobus frontalis, hjernens frontallapp; jf frontallappssyndromet EN frontal lobe.
frontallappssyndromet; eit særleg huglag (sinnelag) som kan koma etter skade i ein pannelapp i hjernen, t d etter lobotomi; pasienten får eit grunt kjensleliv, vert urimeleg overflatisk og lett til sinns, likesæl og godtruande; også kalla frontal psyke; jf Witzelsucht (ty.) EN frontal lobe syndrome. Kilde: Norsk medisinsk ordbok.)
- Spor av "tregere" atferd påvist i hjernen, ifølge studie
Clues to 'Slacker' Behavior Found in Brain, Study Says (Spor av "tregere" atferd påvist i hjernen, ifølge studie)
philly.com 2.5.2012
WEDNESDAY, May 2 (HealthDay News) -- Chemistry in three areas of the brain may influence your motivation levels, a new, small study says.
Along with providing new information about how the brain works, this study could prove important in finding ways to treat depression, schizophrenia, attention-deficit disorder and other types of mental illness linked with decreased motivation, Vanderbilt University researchers said.
The researchers monitored brain activity in 25 volunteers, aged 18 to 29, as they performed a task designed to assess their willingness to work for a cash reward.
The results showed that "go-getters" who were willing to work hard for a reward had higher release of the neurotransmitter dopamine in areas of the brain known to play an important role in reward and motivation -- the striatum and ventromedial prefrontal cortex.
But "slackers" -- those who were less willing to work hard for a reward -- had higher levels of dopamine in a brain area involved in emotion and risk perception, known as the anterior insula. Dopamine's role in this area of the brain surprised the researchers.
"Past studies in rats have shown that dopamine is crucial for reward motivation, but this study provides new information about how dopamine determines individual differences in the behavior of human reward-seekers," study author Michael Treadway, a post-doctoral student, said in a university news release.
The study appears in the May 2 issue of the Journal of Neuroscience. (...)
Willingness to Work Hard Linked to Dopamine Response in Brain Regions (Villighet til å arbeide hardt linket til dopaminrespons i hjerneregioner)
JAMA 2012 (May 2)
Individuals who are willing to work hard even in the face of long odds have a stronger response to dopamine in regions of the brain associated with the reward centers of the brain, according to a new study published the Journal of Neuroscience. Conversely, individuals who are less willing to expend such effort have a greater response to dopamine in an area of the brain linked with social behavior and perception.
Previous work in animals had suggested that the dopamine system in the brain is an important mediator of cost benefit decision-making. These studies had probed the effects of manipulating the dopamine system on animals willingness to pursue food rewards. These studies had either enhanced or blocked the dopamine receptors in the animals. A few human studies had suggested that such manipulations of the dopamine system may also dampen or enhance an individuals willingness to pursue a reward. However, a team of researchers from Vanderbilt University wondered how much individual differences effected human decision-making. So the team recruited 25 healthy volunteers and subjected them both to behavioral testing of their willingness to complete tasks for potential monetary reward and positron emission tomography to measure individual brain responses to dopamine. (...)
- Kokainvaner medfører tidlig aldring av hjernen
Cocaine Habit Ages Brain Prematurely (Kokainvaner medfører tidlig aldring av hjernen)
blogs.scientificamerican.com 24.4.2012
Selv om kokain får folk til å føle seg mer oppmerksom og helt på topp i øyeblikket kan det føre til at brukerne opplever at hjernen fungerer dårligere på lengre sikt. En ny studie viser at viktige deler i hjernen ved kronisk bruk i akselererende grad eldes. Resultatene ble publisert online den 24. april i Molecular Psychiatry. (Although cocaine makes people feel more alert and on top of things in the moment, it can leave users vulnerable to a much slower brain in the long run. A new study shows that chronic use ages key parts of the brain at an accelerated rate. The findings were published online April 24 in Molecular Psychiatry.)
Brukere som regelmessig inntar kokain erfarer ofte kognitiv svikt og hjernesvinn (hjerneatrofi), og nye funn viser hvordan disse brukerne faktisk mister grå hjernemasse mye raskere enn de som ikke bruker midlet. (Regular cocaine users often experience early cognitive decline and brain atrophy, and the new findings show how these users are, indeed, actually losing gray matter in their brain much faster than people who don’t take the drug. )
Karen Ersche ved Behavioral and Clinical Neuroscience Institute ved University of Cambridge og medforfatter av den nye studien uttalte at “vi alle mister grå hjernemasse” når vi eldes. Men hun bemerket at “kroniske kokainbrukere mister grå hjernemasse i signifikant raskere grad, hvilket kan være et tegn på for tidlig aldring.” (“As we age we all lose gray matter,” Karen Ersche of the Behavioral and Clinical Neuroscience Institute at the University of Cambridge and co-author of the new study, said in a prepared statement. But, she noted, “chronic cocaine users lose grey matter at a significantly faster rate, which could be a sign of premature aging.”)
Ersche og hennes kolleger brukte magnetresonanstomografi (MRI) for å studere hjernene til 60 mennesker i alderen 18 til 50 år, som brukte kokain jevnlig, og 60 friske mennesker i tilsvarende alder og IQ, som ikke var brukere. De fant at i gjennomsnitt hos friske individer som ikke brukte midlet årlig mistet 1,7 milliliter grå masse, mens kokainbrukere årlig mistet nærmere 3,1 milliliter. (Ersche and her colleagues used magnetic resonance imaging (MRI) to study the brains of 60 people ages 18 to 50 who used cocaine habitually and 60 healthy people of similar ages and IQs who did not. They found that on average, healthy individuals who didn’t use the drug lost about 1.7 milliliters of grey matter annually, whereas cocaine users were losing closer to 3.1 milliliters each year. )
Kokainbrukere mistet mye mer grå masse i prefrontale og temporale regioner—som hjelper å kontrollere hukommelse, beslutningstaking og oppmerksomhet—enn ikkebrukere gjorde. (Cocaine users lost much more gray matter in the prefrontal and temporal regions—which help control memory, decision-making and attention—than non-users did.)
The find brings a new insight into “why the cognitive deficits typically seen in old age have frequently been observed in middle aged chronic users of cocaine,” Ersche said. Even after the researchers excluded the 16 people from the cocaine group who also had alcohol problems, the trend of accelerated brain mass loss held up.
Of the estimated 21 million cocaine users worldwide, about 1.9 million lived in the U.S. as of 2008. And the largest segment of U.S. users were people ages 18 to 25—some 1.5 percent of whom said they had used cocaine in the past month, according to the National Institutes of Health.
“Unge mennesker som bruker kokain trenger informasjon om langtidsrisiko for tidlig aldring,” sier Ersche. Men hun og hennes kolleger bemerket også at resultatene også bør være oppmerksom på de ekstra kognitive vansker som middelaldrende og eldre voksne substansbrukere i stor grad kan ha i tillegg til avhengighetsproblemer. (...) (“Young people taking cocaine today need to be educated about the long-term risk of aging prematurely,” Ersche said. But she and her colleagues also noted that the results also underscore the extra cognitive needs that middle-aged and older adult drug users seem more likely have in addition to their addiction problems.)
(Anm: Cocaine (benzoylmethylecgonine) (INN) is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant.[5] The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is a stimulant of the central nervous system, an appetite suppressant, and a topical anesthetic. Specifically, it is a serotonin–norepinephrine–dopamine reuptake inhibitor (also known as a triple reuptake inhibitor (TRI)), which mediates functionality of these neurotransmitters as an exogenous catecholamine transporter ligand. It is addicting because of the way it affects the mesolimbic reward pathway.[6] (en.wikipedia.org).
(Anm: Hjernesvinn eller hjerneatrofi er et vanlig trekk ved mange av sykdommene som rammer hjernen. Atrofi av ethvert vev betyr tap av celler. I hjernevevet betyr atrofi tap av nerveceller (nevroner) og forbindelsene mellom dem (nervetrådene, aksoner). Atrofien kan være generell og utbredt, hvilket betyr at hele hjernen har skrumpet, eller den kan være avgrenset (fokal) og rammer bare et mindre område av hjernen. Ved et generelt hjernesvinn vil således mange hjernefunksjoner svekkes, mens fokalt hjernesvinn medfører tap av funksjoner som kontrolleres fra dette området av hjernen. Generelt hjernesvinn der begge hjernehalvdelene er skrumpet, kan føre til mental svekkelse og forstyrrelser av aktiviteter som styres av vår vilje. (nhi.no).)
- Dette er din hjerne på substanser
This Is Your Brain on Drugs (Dette er din hjerne på substanser)
scientificamerican.com 15.5.2012
To the great surprise of many, psilocybin, a potent psychedelic, reduces brain activity (...)
Mescaline, together with psilocybin, another natural psychoactive compound produced by “magic” mushrooms, and lysergic acid diethylamide (LSD or, simply, acid), a potent synthetic psychedelic drug, became widely popular in the 1960s counterculture. The striking similarities between the reports of LSD users and symptoms of acute psychosis led researchers to postulate that serotonin, a chemical-signaling compound or neurotransmitter released by certain groups of neurons in the brain stem, helped to mediate both types of experiences. Indeed, it is now quite certain that the characteristic subjective and behavioral effects of psychedelics are initiated via stimulation of serotonin 2A receptors (known as 5-HT2A) on cortical neurons.
All these hallucinogens were declared controlled drugs in the late 1960s and early 1970s for a variety of medical, political and cultural reasons. Their use moved underground, and research on their psychological, physiological and neuronal effects all but ceased. With the realization of possible therapeutic benefits of psychedelics to reduce anxiety and chronic pain, however, the societal taboos against scientific research on their neurobiology have somewhat relaxed. A number of well-controlled European studies have carefully explored the action of hallucinogens on the brains of normal volunteers [see “Psychedelic Healing?” by David Jay Brown; Scientific American Mind, December 2007/January 2008]. (...)
Turn On, Tune In and Drop Out
The British scientists injected either a harmless saltwater concoction (a placebo) or two milligrams of psilocybin directly into the veins of 30 volunteers while they were lying inside a magnetic scanner. As expected, the subjects experienced within a minute or two the effects of the drug. During their short “trip,” their brains were scanned with one of two different functional MRI techniques. Both gave consistent but very surprising results.
Brain activity was widely reduced! That is, these mind-altering drugs decreased hemodynamic activity, including blood flow, in selected regions, such as the thalamus, the medial prefrontal cortex (mPFC), the ACC and the posterior cingulate cortex (PCC). Activity in these regions dropped by up to 20 percent, relative to before the injection. Even more striking, the deeper the reduction in activity in the ACC and mPFC, the stronger the subject felt the effects of the hallucinogen. Nowhere did activity show an increase. Furthermore, the communication between the PFC and cortical regions in the back of the brain was also disrupted. The surprise is not that reduction of hemodynamic activity in specific sectors of the brain is unheard of. Nor was the activity completely turned off—that would lead within minutes to permanent damage and brain death. (...)
What is intriguing is that the regions that show the strongest reduction in activity are among the most heavily interconnected in the brain. They act like traffic circles or hubs that link disparate regions. Thus, the brain on psilocybin becomes more disconnected, more fragmented, which might explain some of the dissociative aspects of acid trips. Yet why this state should cause the mind-expanding effects that are the prime reason these drugs are treasured is utterly unclear. The study once again highlights how elusive our knowledge of the mind-brain hinge remains. (...)
(Anm: Mescaline. Meskalin (3,4,5-trimetoksyfenetylamin) er et psykedelisk fenetylamin, og er beslektet med stoffer som LSD, psilocybin og 2C-B. Det forekommer naturlig i peyote- og san pedro-kaktusene, og også i en del andre planter i lavere konsentrasjon. (no.wikipedia.org).)
(Anm: Psilocybin er et psykedelisk tryptamin som finnes naturlig i mange sopper i artene Psilocybe (fleinsopper) og Panaeolus. Disse kalles derfor Psilocybinsopper. (no.wikipedia.org).)
Psilocybin Quiets Brain's Control Centers (Psilocybin roer ned hjernens kontrollsenter)
scientificamerican.com 1.5.2012
Psychedelic drugs may work by dialing down brain activity in control centers
Researchers have long suspected that the altered perception, kaleidoscopic visions and mood changes produced by psych¬edelic drugs reflect a jump in brain activity. Not so, say neuroscientists at Imperial College London and elsewhere. They used functional MRI to peek at the brains of 30 participants experiencing a “trip” induced by intravenously delivered psilocybin, a psychedelic found in magic mushrooms. As they reported in the Proceedings of the National Academy of Sciences USA online in January, investigators saw psilocybin-related dips in brain activity, particularly in control centers such as the thalamus, the anterior and posterior cingulate cortices, and the medial prefrontal cortex. The more placid these regions appeared in a participant’s brain, the more intense the subject’s self-reported psychedelic experiences. The scientists conclude that psychedelics temporarily flip off cognition-constraining pathways—including some that are overactive during depression. [For more on this study, click here.] (...)
- Regelmæssig træning øger antallet af mitokondrier i hjernecellerne hos mus
Motion giver mental gevinst
videnskab.dk 28.9.2011
Regelmæssig træning øger antallet af mitokondrier i hjernecellerne hos mus. Det kan forklare nogle af de mentale gevinster, vi oplever ved at holde kroppen i form, mener forskere.
I hver eneste celle i kroppen er der små kraftværker, kaldet mitokondrier. Her omdannes næringsstoffer til energi, som cellerne skal bruge for at fungere.
Tidligere forskning har vist, at regelmæssig træning øger antallet af mitokondrier i muskelcellerne. Det er blevet brugt som del af forklaringen på mange af de positive fysiske effekter af træning – såsom øget udholdenhed og styrke.
Samtidig er det kendt, at træning også virker positivt på det mentale, for eksempel ved at gøre os mere modstandsdygtige over for stress og depressioner.
Det er uklart, hvilke mekanismer der er bag disse mentale træningseffekter. Forskere fra University of South Carolina fremsætter nu en mulig forklaring.
Træning som behandling for psykiske lidelserI et studie af mus har de opdaget, at regelmæssig træning øger antallet mitokondrier i hjernecellerne, skriver forskerne i en pressemeddelelse fra The American Physiological Society.
Forskerne tror, dette er med til at styrke udholdenheden under træning ved at gøre hjernen mere modstandsdygtig mod træthed, som påvirker den fysiske ydeevne.
De antyder også, at forøgelsen af antallet mitokondrier i hjernen kan have kliniske implikationer for psykiske lidelser. Måske kan fysisk træning være en del af behandlingen af psykiske problemer?
»Resultaterne kan føre til bedre atletiske præstationer gennem reduceret mental og psykisk udmattelse.«
»De kan også føre til udvidet brug af træning som en terapeutisk mulighed for at svække de negative effekter af ældning, og til at behandle eller forebygge neurodegenerative sygdomme,« skriver forskerne i deres videnskabelige artikel. (...)
(Anm: Mitochondria (mitokondrie). (mintankesmie.no).)
(Anm: Fysisk trening (aktivitet / løping / jogging). (mintankesmie.no).)
- The one clearly established way to ensure increased BDNF levels in your brain is physical activity
Aging Brain's Decline May Hinge on a Gene (Aldrende hjerne's svekkelse kan være avhengig av et gen)
health.yahoo.com 25.10.2011
TUESDAY, Oct. 25 (HealthDay News) -- Researchers have identified a gene variation that seems to have a major effect on the rate at which men experience an age-related decline in intellectual function.
The study included 144 experienced U.S. male pilots over the age of 40 who took a Federal Aviation Administration-approved flight simulator test three times over two years. The participants included recreational pilots, certified flight instructors and airline pilots.
Using blood and saliva samples from the pilots, the researchers also conducted genetic analyses, looking for the gene that produces a protein called brain-derived neurotropic factor (BDNF). The BDNF gene is considered critical to the development and maintenance of the central nervous system. Levels decline gradually with age, but the findings of this study suggest that a variant of the gene hastens that process.
To test their theory, the researchers divided the pilots into two groups -- those with at least one copy of a BDNF gene that contained the methionine, or "met," variant and those without the variant.
Previous research has linked the "met" variant with increased risk of depression, stroke, anorexia nervosa, anxiety-related disorders, schizophrenia and suicidal behavior. (...)
The study was published online Oct. 18 in the journal Translational Psychiatry.
Staying active can help maintain healthy BDNF levels, the researchers said. "The one clearly established way to ensure increased BDNF levels in your brain is physical activity," Salehi said. (...)
- To minutters daglig træning mod hovedpine
To minutters daglig træning mod hovedpine
arbejdsmiljoviden.dk 10.10.2011
Effektiv styrketræning hver dag kan være med til at forebygge hovedpine hos kontoransatte.
Effektivt middel mod hovedpine
Bare to minutters daglig træning kan mindske kontoransattes anfald af hovedpine markant. Det viser en undersøgelse fra Det Nationale Forskningscenter for Arbejdsmiljø.
Jævnlig hovedpine var noget de 198 kontoransatte i studiet kunne nikke genkendende til. Derfor blev de sat til at styrketræne dagligt med træningselastikker. Og det havde altså en tydelig effekt.
Effekten af styrketræning på hovedpine undersøgt
Hovedpine er ubehageligt og gør det ofte sværere at koncentrere sig om sit arbejde. Personer med smerter i bevægeapparatet har fire gange hyppigere hovedpine end personer uden disse smerter.
Personer med smerter i nakke og skuldre er mere tilbøjelige til at lide af hovedpine end personer med smerter i andre dele af bevægeapparatet. Forskere undersøgte i dette studie, om styrketræning med træningselastikker har nogen effekt på forekomsten af hovedpine. (...)
(Anm: Fysisk trening (aktivitet / løping / jogging). (mintankesmie.no).)
- Streng diett kan holde hjernen frisk
Streng diett kan holde hjernen frisk
vg.no 20.12.2011
Ved å spise mindre kan man holde hjernen frisk, ifølge italienske forskere.
Forskerne har gjennomført en undersøkelse hvor mus ble gitt kun 70 prosent av den næringen de vanligvis ville fått. Dietten førte til aktivering av CREB1, et proteinmolekyl som er viktig for hjernens funksjonsevne.
- Vårt håp er at vi nå kan finne en måte å aktivere CREB1 på, for eksempel gjennom legemidler, slik at hjernen kan holdes ung uten at man trenger å følge en streng diett, sier Giovambattista Pani, som ledet forskningsprosjektet.
Forskernes resultater er lagt fram i siste utgave av forskningstidsskriftet Proceedings of the National Academy of Sciences. (...)
(Anm: Eating less 'can boost your brain and help you remember more'. (dailymail.co.uk 20.12.2011).)
Study: Eating less keeps the brain young
medicalxpress.com 19.12.2011
Overeating may cause brain aging while eating less turns on a molecule that helps the brain stay young.
A team of Italian researchers at the Catholic University of Sacred Heart in Rome have discovered that this molecule, called CREB1, is triggered by "caloric restriction" (low caloric diet) in the brain of mice. They found that CREB1 activates many genes linked to longevity and to the proper functioning of the brain.
This work was led by Giovambattista Pani, researcher at the Institute of General Pathology, Faculty of Medicine at the Catholic University of Sacred Heart in Rome, directed by Professor Achille Cittadini, in collaboration with Professor Claudio Grassi of the Institute ofHuman Physiology. The research appears this week in the Proceedings of the National Academy of Sciences (PNAS).
"Our hope is to find a way to activate CREB1, for example through new drugs, so to keep the brain young without the need of a strict diet," Dr Pani said.
Caloric restriction means the animals can only eat up to 70 percent of the food they consume normally, and is a known experimental way to extend life, as seen in many experimental models. Typically, caloric-restricted mice do not become obese and don't develop diabetes; moreover they show greater cognitive performance and memory, are less aggressive. Furthermore they do not develop, if not much later, Alzheimer's disease and with less severe symptoms than in overfed animals. (...)
- Hjerneslag er hjernens største trussel
Det evig tapte slag?
Are Brean & Christian Lundin, leder og nestleder, Norsk nevrologisk forening (NNF)
aftenposten.no 17.3.2011
Alle tanker og følelser, all bevegelse og all kunnskap har sitt utgangspunkt i hjernen. Samtidig er hjernen ytterst sårbar, skriver kronikkforfatterne.
HJERNESLAG. Hjerneslag er hjernens største trussel. For få hjerneslagpasienter får moderne diagnostikk og behandling i de avgjørende første timene. (...)
Akutt hjerneslag
Ved akutt hjerneslag vil billedundersøkelse med CT eller MR i løpet av minutter fortelle legen hvor i hjernen problemet sitter, om det foreligger en hjerneblødning eller et hjerneinfarkt, og om det er én eller flere blodpropper som stenger for blodstrømmen. Kommer legen raskt til med behandling, det vil si innen tre til fire timer etter starten på hjerneslaget, vil en blodpropp ofte kunne løses opp med «proppløsende» medisin. Slik vil blodstrømmen kunne «skrus på igjen» slik at millioner til milliarder av hjerneceller allikevel overlever.
Jo raskere slik behandling settes i gang, jo bedre er resultatet. Én time etter et hjerneslag har én av to pasienter god effekt av «proppløsende» behandling, etter fire til seks timer dessverre veldig liten. Ved de største hjerneslagene kan man også i noen tilfeller «fiske ut» blodproppen ved hjelp av et kateter som føres fra pulsårene og inn i hjernen. Slik behandling krever høy kompetanse og erfaring, og kan bare utføres ved de aller største sykehusene. Også ved slik behandling er tidsfaktoren helt avgjørende. (...)
Ikke vilje til handling
I organiseringen av hjerteinfarktbehandlingen er moderne kunnskap og nye medisinske behandlingsmuligheter systematisk tatt i bruk. En slik vilje til handling ser ikke ut til å finnes når det gjelder de hjerneslagrammede. Tvert imot. Svært mange slagpasienter sendes til sykehus som hverken kompetansemessig eller teknisk er utstyrt til å tilby god nok diagnostikk og behandling. (...)
Mange sykehus hadde dessuten ingen god oversikt over hvor mange slagpasienter de tok imot eller hvor mange de behandlet med «proppløsende» medisin. (...)
- Ingen søvn betyr ingen nye hjerneceller
No sleep means no new brain cells (Ingen søvn betyr ingen nye hjerneceller)
bbc.co.uk 10.2.2007
Missing out on rest could harm brain cell production
Missing out on sleep may cause the brain to stop producing new cells, a study has suggested.
The work on rats, by a team from Princeton University found a lack of sleep affected the hippocampus, a brain region involved in forming memories.
The research in Proceedings of the National Academy of Science showed a stress hormone causes the effect.
A UK expert said it would be interesting to see if too little rather than no sleep had the same consequence. (...)
(Anm: Søvn (mintankesmie.no).)
(Anm: Sovemidler (sovemedisiner) og beroligende midler (mintankesmie.no).)
- Sömn sorterar ut viktiga minnen
Sömn sorterar ut viktiga minnen
sverigesradio.se 7.2.2011
Att sömn är bra för minnet har forskare tidigare visat. Men nu visar ny forskning från Tyskland att det är när vi sover som hjärnan befäster viktiga minnen och sållar bort andra.
I ett försök fick en grupp personer bland annat lära sig att komma ihåg ord och matcha ihop bilder på djur med bilder på olika saker.
Tio timmar senare testades deltagarna för att se hur mycket de kom ihåg. Några visste om att de skulle testas, men inte alla.
Det visade sig att de som fick sova innan de testades kom ihåg sina uppgifter bättre än de som inte fått sova något. Men allra bäst presterade de som fick sova och visste att de skulle testas senare. Mätningar visade också att de som presterade bäst hade en ökad hjärnaktivitet under djupsömnen.
Forskarna föreslår att det är den främre delen av hjärnbarken som väljer ut vilka minnen som är av störst vikt när vi är vakna, Men att själva utsållningen av minnen sen sker i hippocampus medan vi sover.
- Nytt ljus på hjärnans åldrande
Nytt ljus på hjärnans åldrande
sverigesradio.se 13.12.2010
Forskarna menar att de här fynden ifrågasätter resultaten som flera rådande teorier om hjärnans åldrande kommer ifrån.
Svenska forskare presenterar nu en delvis ny syn på hur vår hjärna förändras med tiden. Deras slutsatser borde enligt dom själva ifrågasätta tidigare forskningsstudier. (...)
Svenska forskare presenterar nu en delvis ny syn på hur vår hjärna förändras med tiden. Deras slutsatser borde enligt dom själva ifrågasätta tidigare forskningsstudier.
För att upptäcka skillnader så har man då jämfört bilder av yngre personers hjärnor med äldre personers och funnit att frontalloberna hos de äldre tycks visa högre aktivitet. Dessa resultat har framkommit ur så kallade tvärsnittsstudier, alltså studier som jämfört olika grupper vid ett undersökningstillfälle.
Stor uppmärksamhet
Fynden har väckt stor uppmärksamhet eftersom de tolkats som att hjärnan kan omorganisera sitt sätt att fungera för att kompensera åldersförändringarna.
Men, enligt denna nya studies forskare är det svårt att dra sådana slutsatser från enkla tvärsnittsstudier. De menar att det krävs en longitudinell studie, alltså en studie där man följer personer över en längre tid för att säkerställa bevisen. (...)
- Magbakterier hjälper hjärnan att utvecklas
Magbakterier hjälper hjärnan att utvecklas
sverigesradio.se 1.2.2011
Vanliga bakterier kan ha stor betydelse för hjärnans utveckling. Det visar en studie på möss som svenska forskare har gjort. Mössen i studien som inte utsattes för några bakterier fick beteendestörningar som påminner om människors ADHD.
Magbakterier på nyfödda möss hjälper hjärnan att utvecklas bra. Hans Forssberg, professor i neurovetenskap på Karolinska institutet i Solna. Reporter Lars Broström, Lägg till i spelkö Spara som favoritklipp Dela Facebook Twitter Digg Del.icio.us Direkt länk till ljudet Öppna i spelaren
– Det vi ser är att de djur som inte får bakteriesignalen när de föds, de är hyperaktiva och tar större risker, säger Hans Forssberg, som är professor i neurovetenskap på Karolinska institutet i Solna och en av förskarna bakom studien. (...)
- Hvordan alkohol skader hjernen
How Alcohol Damages the Brain (Hvordan alkohol skader hjernen)
Ivanhoe.com 17.6.2011
(Ivanhoe Newswire) -- Although alcohol affects many areas in the body, the brain is the primary target. Previously, not much was known about the molecular mechanisms by which alcohol alters brain activity, but now researchers have discovered interaction between alcohol and brain proteins thought to underlie alcohol actions in the brain.
"Alcohol is the most common drug in the world, has been used by diverse human communities longer than recorded history, yet our understanding of its effects on the brain is limited when compared to other drugs," Rebecca J. Howard, a postdoctoral fellow at The University of Texas at Austin Waggoner Center for Alcohol & Addiction Research and corresponding author for this study, was quoted as saying.
Howard explained that neuroscientists have discovered how marijuana, cocaine, and heroin each bind to a special type of protein on the surface of brain cells, fitting like a key into a lock to change that protein's normal function. Yet alcohol has special properties that make it difficult to characterize its lock-and-key binding in detail, for example, alcohol is much smaller than other drugs, and appears to interact with several different types of proteins.
"One major problem in studying alcohol binding to brain proteins is that the alcohol key does not fit very tightly into any particular protein lock," said Howard. (...)
- Fire faktorer som kan krympe din hjerne
Study: 4 Factors That May Shrink Your Brain (Studie: Fire faktorer som kan krympe din hjerne)
healthland.time.com 3.8.2011 (Time)
Your brain is bound to shrink as you age — it's unavoidable. But there are certain lifestyle factors that hasten the process, according to a new study by researchers at University of California, Davis.
The four factors that were associated with faster declines in brain volume were:
- High blood pressure
- Diabetes
- Cigarette smoking
- Being overweight or obese
The study included 1,352 adults who had an average age of 54 and did not have dementia at the start of the study. All were participants of the Framingham Offspring Cohort Study (the children of the participants of the original Framingham Heart Study).
To start, researchers administered a battery of tests, including measures for obesity, high blood pressure, diabetes and high cholesterol. Starting seven years later, they measured the participants' brain size using MRI scans and also gave participants cognitive tests to gauge executive function, planning and organizational skills.
The researchers found that all four risk factors were associated with faster declines in brain size: people with high blood pressure in midlife more quickly developed a condition called white matter change, in which areas of blood vessels in the brain are damaged, compared with those who had normal blood pressure.
People with diabetes had faster shrinkage in a brain region called the hippocampus, which is involved with memory. Smokers had more rapid overall brain shrinkage than nonsmokers, and also showed faster white matter changes. (...)
Brain 'can beat early blindness'
Brain 'can beat early blindness'
bbc.co.uk 17.2.2007
The brain can learn to see in later life even if it has been deprived of visual input early on, work suggests.
One woman, who had her vision restored at the age of 12 by a cataract operation, performed almost normally on vision tests at the age of 32.
US experts say their studies show the brain is malleable in older children - which was doubted previously - and that the risks of surgery can be worth it.
And they have launched an initiative to treat blind children living in India. (...)
Science Tracks How the Brain's 'Clock' Ticks
Science Tracks How the Brain's 'Clock' Ticks
healthfinder.gov 2.2.2007
-- Scientists have developed a new model of how the brain tells time, which challenges the popular theory of an internal clock that generates and counts regular fixed moments.
Researchers at the University of California, Los Angeles, suggest that a series of physical changes to the brain's cells help it track the passage of time. (...)
- Duke scientists map part of brain
Duke scientists map part of brain
heraldsun.com 14.1.2007
Neuroscientists at Duke University have mapped the timing and sequence of neural activations that unfold in the brain when people focus their attention on specific locations in their visual fields. (...)
The findings appear in the January issue of the journal Public Library of Science Biology. The research was supported by the National Institute of Mental Health and the National Institute of Neurological Diseases and Stroke.
In this study, the researchers combined information from two different technologies for measuring brain activity in order to provide insight into the basic mechanisms by which humans orient and focus their visual spatial attention. (...)
An example of the kind of focused visual attention the researchers investigated is what happens as a motorist watches traffic in front of his car while also monitoring out of the corner of his eye the movement of a bicyclist pedaling on the side of the road. This example is illustrated on Woldorff's laboratory Web site at www.mind.duke.edu/faculty/woldorff.
"When we direct our attention to such specific locations or events -- in this case, the bicyclist off to the side -- we tend to more quickly discriminate or detect changes there than at other locations in our visual field that are not so attended," Woldorff said. (...)
- Brain power unlocked frontal cortex mystery
Brain power unlocked frontal cortex mystery
latimes.com 2.4.2007
Pinpointing regions responsible for certain personality traits started with a railroad foreman's unfortunate accident.
It took centuries for scientists to figure out that the brain's frontal cortex, which sits just behind the forehead, governs emotions and reasoning. One important early clue came from an accident a young railroad worker suffered in 1848. The worker, Phineas Gage, went on to become one of the most famous brain-injury patients of all time. (...)
- Hukommelsen kan undertrykkes
Hukommelsen kan undertrykkes
Tidsskr Nor Lægeforen 2007; 127: 2213
Undertrykkelse av emosjonell hukommelse kan betraktes som en dynamisk prosess som skjer i to faser og som involverer prefrontale regioner.
Det er uavklart om hukommelsen kan manipuleres og undertrykkes. Amerikanske forskere har nå undersøkt om uønskede erindringer lar seg undertrykke og hvordan dette i så fall skjer (1). (...)
- Hjärna aktiv även i koma
Hjärna aktiv även i koma
svd.se 8.9.2006
Hjärnundersökningar av en 23-årig brittisk kvinna som varit i det som kallas vegetativt tillstånd i fem månader avslöjar tidigare otänkbara aktiviteter i hennes hjärna. Otroligt fascinerande och spektakulärt, säger experterna om de nya upptäckterna som kan leda till nya sätt att undersöka svåra hjärnskador. (...)
- Hjernen tar valg før du vet det
Kan hindre hjernen i å gjøre feil
vg.no 22.4.2008
Ny forskning viser at hjernen oppfører seg annerledes ca. 30 sekunder før folk gjør en rutinefeil. I fremtiden kan personer som har arbeid med stort ansvar bli varslet før de begår en feil, håper hjerneforskere. (...)
Hjernen tar valg før du vet det
vg.no 15.4.2008
(VG Nett) Ved å skanne aktiviteten i hjernen din, kan forskerne forutsi hvilke valg du tar flere sekunder før du selv vet det. (...)
- Vi mener våre beslutninger er bevisste, men disse dataene viser at bevisstheten er bare toppen av isfjellet, sier John-Dylan Haynes fra Max Planck Institute for Human Cognitive and Brain Science i Leipzig til Nature News. (...)
Rutinefeil skyldes omkobling i hjernen
uib.no 22.4.2008
Ny forskning viser at hjernen oppfører seg annerledes ca 30 sekunder før folk gjør en rutinefeil. I fremtiden kan personer som har arbeid med stort ansvar, bli varslet før de begår en feil.
Tradisjonelt har forskerne ment at når vi gjør en feilhandling er det «den menneskelige faktor» som slår inn. Vi gjør en tilfeldig feil på slump, slik er det bare. Man har trodd at det først er i etterkant av feilhandlingen at hjernen reagerer.
Men nye resultater fra fMRI-gruppen ved Psykologisk fakultet og Haukeland universitetssykehus snur opp ned på den vante forestillingen. Når vi gjør feil i en rutinepreget handling, kommer hjernens aktivitet på en måte ut av spor i forkant av handlingen. Dette skyldes at nevronene ikke er synkronisert på den måten de er når man gjør en riktig handling.
Resultatene publiseres i dag i det amerikanske tidsskriftet PNAS, med Tom Eichele som førsteforfatter. Funnene er så viktige at grunnleggende litteratur om emnet må skrives om. (...)
- Psykologi: Hvorfor noen ikke lærer av sine feil
Oops, I Did It Again
msnbc.msn.com 24.4.2007
New brain research may help explain why some people don't seem to learn from their mistakes.
New brain research may help explain why some people don't seem to learn from their mistakes.
- Benjamin Franklin was no brain scientist. He was a keen observer of human behavior, and of the natural world, but he was a couple centuries too early to explore the intricate neuronal interplay of physics and biochemistry that makes us the people we are: healthy, wise, quirky, self-destructive. So, when he famously defined insanity as "doing the same thing over and over and expecting different results," this 18th-century polymath was really being more intuitive than rigorously scientific. (...)
- Nye teorier linker depresjon til kronisk hjernebetennelse
New Theory Links Depression To Chronic Brain Inflammation (Nye teorier linker depresjon til kronisk hjernebetennelse)
medicalnewstoday.com 21.10.2010
Chronic depression is an adaptive, reparative neurobiological process gone wrong, say two University of California, San Diego School of Medicine researchers, positing in a new theory that the debilitating mental state originates from more ancient mechanisms used by the body to deal with physical injury, such as pain, tissue repair and convalescent behavior.
In a paper published in the September online edition of Neuroscience and Biobehavioral Review, Athina Markou, PhD, professor of psychiatry, and Karen Wager-Smith, a post-doctoral researcher, integrate evidence from diverse clinical, biological and behavioral studies to create a novel theory they hope will lead to a shift in thinking about depression.
"In contrast to other biological theories of depression, we started with a slightly different question," said Wager-Smith. "Other theories address the question: 'What is malfunctioning in depression?' We took a step back and asked the question: 'What is the biology of the proper function of the depressive response?' Once we had a theoretical model for the biology of a well-functioning depressive response, it helped make sense of all the myriad differences between depressed and non-depressed subjects that the biomedical approach has painstakingly amassed." (...)
- Depresjoner og nedsatt læringsevne settes i sammenheng med forurensa luft etc. (og betennelsesskader i hjernen)
Luftforurensning kan skade hjernen
nrk.no 6.7.2011
Depresjoner og nedsatt læringsevne settes i sammenheng med forurensa luft i ny forskningsrapport.
At hjerte og lunger påvirkes av forurensa luft er noe vi har visst lenge. Men nå viser en ny rapport at også hjernen kan ta skade av luftforurensning.
– Resultatene viser at det å være eksponert for forurensa luft over lang tid kan ha tydelige negative konsekvenser for hjernen, noe som kan føre til flere forskjellige helseproblemer, sier Laura Fonken til Science Daily.
Et halvt museliv
Fonken har leda undersøkelsa, som nylig ble publisert i Molecular Psychiatry.
Forskergruppa eksponerte mus for enten filtrert eller forurensa luft - seks timer daglig, fem dager i uka i ti måneder. Dette tilsvarer omtrent halve livet for ei mus.
Den forurensa lufta inneholdt ultrafine partikler på rundt 2,5 mikrometer i diameter, og konsentrasjonen tilsvarte den mennesker kan bli utsatt for i enkelte forurensa bymiljø.
Les: Forurensning gjør frosk tvekjønnet (...)
Betennelsesskader i hjernen
For å finne ut mer om den konkrete sammenhengen mellom forurensning og hjernevirksomhet studerte forskerne de utsatte musenes hjerner.
– Vi ville se nøye på hippocampus siden den er knytta til læring, hukommelse og depresjon, forklarer Fonken.
De fant tydelige fysiske forskjeller mellom musehjernene som hadde vårt utsatt for forurensning og de som ikke hadde vært det.
De skada hjernene hadde blant annet kortere utløpere fra nervecellene i hippocampus, og redusert cellekompleksitet.
– Tidligere forskning har vist at disse typer skader kan knyttes til nedsatt læring- og huskeevne, forteller professor Randy Nelson, som også har vært med på studien, til Science Daily.
Flere tidligere studier har vist at massiv eksponering for forurensa luft kan føre til betennelser i kroppen.
– Hippocampus er spesielt sensitiv for skader som er forårsaka av betennelse, sier Fonken. (...)
(Anm: Cytokiner Cytokiner är små proteiner (under kDa) som fungerar som signalmolekyler mellan celler och produceras av immunförsvaret, både det medfödda och det adaptiva immunförsvaret. (sv.wikipedia.org).)
Air pollution impairs cognition, provokes depressive-like behaviors and alters hippocampal cytokine expression and morphology (Luftforurensning svekker kognisjon, utløser depresjonsliknende atferd og endrer hippocampal cytokin uttrykk og morfologi)
Mol Psychiatry. 2011 Jul 5. doi: 10.1038/mp.2011.76. [Epub ahead of print]
Abstract Particulate matter air pollution is a pervasive global risk factor implicated in the genesis of pulmonary and cardiovascular disease. Although the effects of prolonged exposure to air pollution are well characterized with respect to pulmonary and cardiovascular function, comparatively little is known about the impact of particulate matter on affective and cognitive processes. The central nervous system may be adversely affected by activation of reactive oxygen species and pro-inflammatory pathways that accompany particulate matter pollution. Thus, we investigated whether long-term exposure to ambient fine airborne particulate matter (<2.5 μm (PM(2.5))) affects cognition, affective responses, hippocampal inflammatory cytokines and neuronal morphology. Male mice were exposed to either PM(2.5) or filtered air (FA) for 10 months. PM(2.5) mice displayed more depressive-like responses and impairments in spatial learning and memory as compared with mice exposed to FA. Hippocampal pro-inflammatory cytokine expression was elevated among PM(2.5) mice. Apical dendritic spine density and dendritic branching were decreased in the hippocampal CA1 and CA3 regions, respectively, of PM(2.5) mice. Taken together, these data suggest that long-term exposure to particulate air pollution levels typical of exposure in major cities around the globe can alter affective responses and impair cognition.Molecular Psychiatry advance online publication, 5 July 2011; doi:10.1038/mp.2011.76. (...)
- Ständig smärta stör hjärnans återhämtning
Ständig smärta stör hjärnans återhämtning
lakemedelsvarlden.se 19.2.2008
Kronisk smärta stör balans och viloläge i hjärnan och kan leda till andra hälsoproblem som depression, oro, sömnstörningar och svårigheter att fatta enkla beslut. Det visar en ny studie i Journal of Neuroscience. (...)
Detta påslag av smärtsignaler stör i jämvikten i hjärnan och kan förändra nervsignalerna permanent och skada hjärnan, menar forskarna. (...)
I en frisk hjärna samverkar alla områden i hjärnan och uppehåller en form av jämvikt och när en region är aktiv dämpas aktiviteten i andra områden. Men hos personer med kronisk smärta dämpas aldrig aktiviteten, vilket förändrar balansen med andra områden. (...)
Forskarna poängterar att dessa förändringar kan göra det svårt för personer att fatta beslut eller att vara på gott humör och utvilad när man stiger upp på morgonen. (...)
Beyond Feeling: Chronic Pain Hurts the Brain, Disrupting the Default-Mode Network Dynamics
Journal of Neuroscience 2008;28(6):1398-1403
Chronic pain patients suffer from more than just pain; depression and anxiety, sleep disturbances, and decision-making abnormalities (Apkarian et al., 2004a) also significantly diminish their quality of life. (...)
These findings demonstrate that chronic pain has a widespread impact on overall brain function, and suggest that disruptions of the DMN may underlie the cognitive and behavioral impairments accompanying chronic pain. (...)
Chronic Pain Harms Brain's Wiring
yourtotalhealth.ivillage.com 11.2.2008
Feb. 11 (HealthDay News) -- Chronic pain can disrupt brain function and cause problems such as disturbed sleep, depression, anxiety and difficulty making simple decisions, a U.S. study finds. (...)
But in people with chronic pain, the front region of the cortex mostly associated with emotion "never shuts up," study author Dante Chialvo, an associate research professor of physiology, said in a prepared statement.
This region remains highly active, which wears out neurons and alters their connections to each other. This constant firing of neurons could cause permanent damage.
"We know when neurons fire too much they may change their connections with other neurons or even die, because they can't sustain high activity for so long," Chialvo said. (...)
These changes "may make it harder for you to make a decision or be in a good mood to get up in the morning. It could be that pain produces depression and the other reported abnormalities, because it disturbs the balance of the brain as a whole," he said. (...)
- Hjernen og immunsystemet
Glutenintolerans kopplas till psykos
dagensmedicin.se 11.5.2012
Barn som föds av mammor med antikroppar mot gluten kan senare i livet ha en ökad risk att drabbas av psykos, visar en svensk studie i tidskriften American Journal of Psychiatry.
Det är forskare vid bland annat Karolinska institutet i Solna som undersökt 211 svenskar som fått diagnosen icke affektiv psykossjukdom, det vill säga psykossjukdom som inte präglas av återkommande maniska eller depressiva perioder.
Forskarna analyserade nivåerna av antikroppar mot glutenämnet gliadin som studiedeltagarna hade vid födseln. Höga nivåer av sådana antikroppar antyder att modern är intolerant mot gluten.
Resultaten visar att personerna med psykos oftare hade höga nivåer av antikroppar mot gliadin, jämfört med en grupp kontrollpersoner med motsvarande ålder, kön, födelsesjukhus och hemort.
Barn till mödrar som har höga nivåer av sådana antikroppar skulle enligt forskarnas beräkningar ha 70 procents ökad risk att senare i livet drabbas av psykossjukdom.
– Det finns studier som visar att personer som diagnostiserats med schizofreni oftare också drabbas av olika former av immunreaktioner mot gluten. Vi ska nu göra en uppföljande studie för att undersöka om kopplingen mellan schizofreni och gluten enba rt gäller de som har en genetisk förutsättning eller om det kan vara någon annan mekanism inblandad, säger forskaren Håkan Karlsson i ett pressmeddelande från Karolinska institutet.
Läs abstract till studien:
Autoimmunity in psychiatry
The British Journal of Psychiatry (2012) 200: 353-355 (May)
Abstract
Current knowledge of the role of autoimmunity in the pathogenesis of the main psychiatric disorders is briefly outlined. The significance of immunological effects on synaptic transmission and associated neuropsychiatric syndromes is emphasised. Clinical psychiatrists are encouraged to keep abreast of developments in this increasingly important area. (...)
Prevalence of autoimmune diseases in in-patients with schizophrenia: nationwide population-based study
British Journal of Psychiatry 2012 (Published online ahead of print March 22)
Background
The association between autoimmune diseases and schizophrenia has rarely been systematically investigated.
Aims
To investigate the association between schizophrenia and a variety of autoimmune diseases and to explore possible gender variation in any such association.
Method
Taiwan’s National Health Insurance Research Database was used to identify 10 811 hospital in-patients with schizophrenia and 108 110 age-matched controls. Univariate and multiple logistic regression analyses were performed, separately, to evaluate the association between autoimmune diseases and schizophrenia. We applied the false discovery rate to correct for multiple testing.
Results
When compared with the control group, the in-patients with schizophrenia had an increased risk of Graves’ disease (odds ratio (OR) = 1.32, 95% CI 1.04–1.67), psoriasis (OR = 1.48, 95% CI 1.07–2.04), pernicious anaemia (OR = 1.71, 95% CI 1.04–2.80), celiac disease (OR = 2.43, 95% CI 1.12–5.27) and hypersensitivity vasculitis (OR = 5.00, 95% CI 1.64–15.26), whereas a reverse association with rheumatoid arthritis (OR = 0.52, 95% CI 0.35–0.76) was also observed. Gender-specific variation was found for Sjögren syndrome, hereditary haemolytic anaemia, myasthenia gravis, polymyalgia rheumatica and dermatomyositis.
Conclusions
Schizophrenia was associated with a greater variety of autoimmune diseases than was anticipated. Further investigation is needed to gain a better understanding of the aetiology of schizophrenia and autoimmune diseases. (...)
Bone Marrow Transplants Alleviate Symptoms of Rett Syndrome in Mice
sciencemag.org 2012 (18 March)
(...) The new study hints at a very different approach. A team led by neuroimmunologists Noël Derecki and Jonathan Kipnis of the University of Virginia in Charlottesville set out to explore a hypothesis that had received little if any previous consideration: that immune cells called microglia might play a role in Rett syndrome. (...)
Infeksjon hos gravide kan gi økt risiko for epilepsi hos barnet
fhi.no 20.3.2012
En studie Folkehelseinstituttet har vært med på antyder økt fare for epilepsi hos barnet dersom mor brukte antibiotika eller var sykehusinnlagt for infeksjon under svangerskapet.
Studien er utført i Danmark ved Avdeling for klinisk epidemiologi ved Århus universitets hospital. Fra Folkehelseinstituttet har professor og overlege Leiv Sigmund Bakketeig deltatt.
Studien antyder en 40 % økt risiko for epilepsi dersom mor brukte antibiotika i svangerskapet eller var sykehusinnlagt for infeksjon. (...)
Antibody-mediated encephalitis: a treatable cause of schizophrenia
Editorial
The British Journal of Psychiatry (2012) 200: 92-94 (February)
Psychiatrists need to be vigilant for the newly recognised and treatable disorder of antibody-mediated encephalitis. Psychiatric symptoms are common, and individuals with the disorder often present initially to psychiatric services. We describe the clinical features of the disorder and make recommendations for further investigations. (...)
Kirurgi kan försämra minnet
svd.se 29.12.2011
Kirurgiska ingrepp påverkar minnet och koncentrationen. En ny studie har kartlagt signalvägarna och upptäckt att kirurgiska ingrepp kan ge skador på blodhjärnbarriären som leder till inflammation i hjärnan viket kan förhindras genom tillförsel av nikotinliknande läkemedel. (...)
Många patienter som genomgått kirurgiska ingrepp kan drabbas av störningar av koncentration, minne och inlärningsförmåga. Komplikationerna kan drabba i övrigt helt friska patienter en längre tid efter ingreppet. Studien har gjorts av en forskargrupp vid Karolinska institutet tillsammans med forskare vid University of California i San Francisco, USA.
– Denna typ av störningar är en av de vanligaste långtidseffekter efter ett kirurgiskt ingrepp. Även om operation har förlöpt bra så hänger det kvar en oförmåga att koncentrera sig. Ett exempel kan vara att man har svårt att koncentrera sig under ett samtal, säger Lars I Eriksson, professor i anestesiologi och intensivvård vid Karolinska Institutet.
Mellan 20 och 25 procent av patienterna drabbas av dessa problem under de första veckorna efter ingreppet. För cirka 10 procent kvarstår effekterna i tre månader och för enstaka fall kan det vara problem med koncentrationen, minnet och inlärningsförmågan i över ett år.
– Det är ett stort problem för många människor, ett problem som ökar och som vi hittills inte känt till vad det beror på. Det vi har märkt av är att äldre har en större risk att drabbas än yngre, säger Lars I Eriksson.
Studien som enligt forskarna är ett genombrott i förståelsen av hur störningar uppstår efter kirurgi visar att ingreppet orsakar inflammatoriska förändringar i de delar av hjärnan som deltar i kognitiva funktioner.
– Vi visar hur ingreppet ökar inflammatoriska proteiner som i sin tur skadar blodhjärnbarriären, vilket möjliggör för immunkompetenta blodceller passerar in i de delar av hjärnan som deltar i kognitiva processer, säger Lars I Eriksson som även undersökt en lösning på problemet. (...)
Childhood disorder bolsters research on infection link
seattletimes.nwsource.com 14.12.2011
Children have obsessive-compulsive disorder that occurs suddenly — and often dramatically — within days or weeks of a simple infection, such as strep throat. (...)
The bizarre illness, first recognized in the mid-1990s, has been cloaked in controversy. Now, however, studies are reinforcing the belief that some psychiatric illnesses can be triggered by ordinary infections and the body's immune response. The theory remains unproved, but the research raises the possibility that some cases of mental illness might be cured by treating the immune system dysfunction.
"Some people get sick with whatever infection, and they recover and they're fine," says M. Karen Newell Rogers, an immunologist at Texas A&M University School of Medicine in Temple, Texas, who studies such illnesses. "Other people get sick and recover, but they are not the same."
PANDAS is thought to be caused by antibodies generated as a result of an infection, usually strep. Normally, the antibodies fight the infection and promote healing. But in PANDAS, the antibody response is thought to go awry, attacking brain cells and resulting in OCD symptoms.
A greater understanding of the link between strep and OCD has opened the door to the study of other psychiatric or neurological illnesses that may be linked to improper immune response, including cases of autism, schizophrenia and anorexia.
"The whole area of mental illness caused by infections is being looked at more closely because of PANDAS," says Dr. Michael A. Jenike, a professor of psychiatry at Harvard Medical School and chairman of the International OCD Foundation's scientific advisory board. "If you can prevent lifelong suffering by using antibiotics or some acute intervention, that would be huge." (...)
Are Telomere Tests Ready for Prime Time?
Science 2011;332 (6028):414-415
Summary
Can the length of our telomeres, the protective caps at the ends of chromosomes that wear down as we get old, predict how well our bodies will age and our vulnerability to chronic diseases? Two new companies, both with heavyweight academic backing, are betting on it and have started or are planning to start performing telomere tests for the general public this year. But other leading telomere scientists say such tests are premature, if not virtually useless. On opposite sides of the issue are former collaborators Elizabeth Blackburn and Carol Greider, who, along with Jack Szostak of Harvard Medical School, shared the 2009 Nobel Prize in physiology or medicine for their telomere discoveries. (...)
(Anm: Are Telomere Tests Ready for Prime Time? Science 22 April 2011: 414-415 (22 April).)
Chronic Depression Linked To Accelerated Immune Cell Aging
medicalnewstoday.com 6.4.2011
Certain cases of major depression are associated with premature aging of immune cells, which may make people more susceptible to other serious illness, according to findings from a new UCSF-led study.
The findings indicate that accelerated cell aging does not occur in all depressed individuals, but is dependent upon how long someone is depressed, particularly if that depression goes untreated. The study was published online in March 2011 by the journal PLoS One.
"There's a lot more to depression than feeling blue," said first author Owen Wolkowitz, MD, a professor of psychiatry at UCSF. "As if feeling depressed is not bad enough, we are finding that long-term depression may be associated with damage to cells in the body, and this may predispose patients to certain physical diseases."
Previously considered a mental illness affecting only the brain, major depressive disorder, or MDD, now is believed to be tied to significant physical damage outside the brain, explained Wolkowitz. For example, depressed individuals are more likely to develop the diseases of advanced age, including diabetes, heart disease, osteoporosis, stroke and dementia.
In probing the links between depression and physical disease, the research team explored aging of the immune system as measured by the shortening of telomeres in immune cells taken from the blood.
Telomeres are tiny units of DNA-protein complexes that seal off and protect the ends of chromosomes and act as a biological clock controlling a cell's life. Telomere shortening predicts earlier onset of several major age-related diseases and earlier mortality, and may serve as one index of human longevity. (...)
Cannabis hemmer immunforsvaret
aftenposten.no 1.4.2011
Den kjemiske forbindelsen tetrahydrocannabinol, THC, i cannabis påvirker immunforsvaret. Det er også denne forbindelsen som gjør en «høy» når man røyker hasj eller marihuana. Forsøk med mus viser at THC forårsaker en massemobilisering av celler som demper immunforsvaret, har forskere ved universitetet i south Carolina funnet ut. Cellene kalles MDsCs (myeloidderived suppressor cells), og deres effekt på immunforsvaret gjør kroppen åpen for infeksjoner av alle slag, samt visse former for kreft. (...)
Cannabis Use and Earlier Onset of Psychosis (Bruk av cannabis og tidlig utvikling av psykose)
Arch Gen Psychiatry. 2011;68(6):555-561 (June)
A Systematic Meta-analysis
Conclusions The results of meta-analysis provide evidence for a relationship between cannabis use and earlier onset of psychotic illness, and they support the hypothesis that cannabis use plays a causal role in the development of psychosis in some patients. The results suggest the need for renewed warnings about the potentially harmful effects of cannabis. (...)
Neuroleptic malignant syndrome: a neuroimmunologic hypothesis
CMAJ 2010;182 E834-E838 (December)
Are Depressed People Too Clean? (Er deprimerte mennesker for rene)
medicalnewstoday.com 9.12.2010
In an effort to pinpoint potential triggers leading to inflammatory responses that eventually contribute to depression, researchers are taking a close look at the immune system of people living in today's cleaner modern society.
Rates of depression in younger people have steadily grown to outnumber rates of depression in the older populations and researchers think it may be because of a loss of healthy bacteria.
In an article published in the December issue of Archives of General Psychiatry, Emory neuroscientist Charles Raison, MD, and colleagues say there is mounting evidence that disruptions in ancient relationships with microorganisms in soil, food and the gut may contribute to the increasing rates of depression. (...)
Cannabis hämmar immunförsvaret
svt.se 29.11.2010
Cannabis kan ge ökad risk för cancer och infektioner.
Marijuanarökning kan utlösa en dämpning av kroppens immunförsvar. Nu har forskarna funnit varför brukare av cannabis är mer mottagliga för vissa typer av cancer och infektioner.
Cannabis är en av de mest använda missbruksdrogerna i världen. Man har länge misstänkt att en av effekterna är en försvagning av immunförsvaret. Nu tror forskarna att orsaken till dämpningen är en nyligen upptäckt typ av immunceller, kallade MDSC. (...)
(Anm: cannabis, eller cannabispreparater, fellesnavn for de narkotiske stoffene som utvinnes av en underart av hamp (...) Det er toppskuddene og hunnblomsterstanden som gir de forskjellige produktene: marihuana, hasjisj, hasjolje og andre cannabispreparater. Kilde: Store norske leksikon.)
(Anm: Marihuana (marijuana) (mintankesmie.no).)
Barnmisshandel kan påskynda kroppens åldrande
dn.se 21.11.2009
Fysisk eller psykisk misshandel under uppväxten kan påskynda kroppens åldrande, det visar en stuide utförd av amerikanska forskare.
Det är ett team från Brown University som forskar kring telomererna, de skyddande locken på kromosomerna som håller cellens DNA stabilt, som kommit fram till resultatet.
Teamet fann att telomererna hos personer som utsatts för misshandel eller övergrepp under barndomen tenderade att kortas ned snabbare än hos andra människor, skriver brittiska BBC. (...)
Studien utfördes på 31 personer. Professor Tim Spector vid King's College i London, som forskar om telomerer och åldrande, säger till BBC att studien är intressant, men att den måste upprepas i större skala för att vi ska kunna vara säkra på dess slutsatser.
2009 års Nobelpris i medicin gick till tre forskare som bidrog till upptäckten av telomerer. (...)
(Anm: Barnevern, omsorgssvikt, barnemishandling og barnedrap. (mintankesmie.no).)
Hjernen og immunsystemet
Tidsskr Nor Lægeforen 1995; 115: 954-8
Hjernen er ekstremt følsom for endringer i det lokale miljø. En lokal immunreaksjon i hjernen kan være fatal, selv om den kan stanse en infeksjon. Fra et utviklingsmessig standpunkt er dette problem løst ved at hjernen er isolert, både fra invaderende mikroorganismer og fra immunsystemet som skulle angripe disse mikroorganismene. Denne isolasjon skyldes spesielle trekk ved nervesystemets oppbygning: blod-hjerne-barrieren, hjernens antatte mangel på lymfedrenasje og fravær av vevsantigener (major histocompatibility complex) - MHC-molekyler - på hjernecellene. Blod-hjerne-barrieren blokkerer immunceUer og sirkulerende molekyler fra immunsystemet fra å nå hjernen.
Mangelen på lymfeårer forhindrer at immunogent materiale når regionale lymfeknuter. Og mangelen på MHC-molekyler fører til et immunologisk inaktivt miljø. Hjernen mangler således enkelte komponenter av immunsystemet, og den deltar under normale forhold ikke i immunreaksjoner.
Men denne isolasjon fører til at hjernen er særlig vulnerabel overfor infeksjoner. Forsvarssystemene er så svake at infeksjoner som i seg selv kan være uskyldige, kan få alvorlige konsekvenser om de kommer innenfor hjernens barrierer. Det er også likhetspunkter mellom nervesystemet og immunsystemet. Begge består av celler som påvirker hverandre ved kjemiske signaler. Det er økende holdepunkter for at de to systemer også kan kommunisere; at hjernens transmittere kan påvirke lymfocyttenes funksjon, og at enkelte lymfokiner som produseres under en immunreaksjon, også kan virke som signalsubstanser i hjernen.
Forholdet mellom hjernen og immunsystemet er derfor et samspill mellom hjernens immunologiske isolasjon, dens følsomhet for immunologiske reaksjoner og spørsmålet om hjernen også kan ha funksjoner som et overordnet immunologisk organ. (...)
Blod-hjerne-barrieren
Hjernen er meget godt beskyttet mot påvirkninger utenfra. Skallen og hjernehinnene gir et vern mot ytre infeksjoner. Det er også effektive beskyttelser mot infeksjoner fra innsiden.
For å vise hvordan de fungerer. Kan det være nyttig å sammenlikne to viktige organer: hjernen og leveren.
Begge organer har en rik blodforsyning. Arteriene deler seg i mindre grener som til sist ender i et kapillærnett. Men mens leverens kapillærer har fenestrerte endotelceller med store åpninger mellom de enkelte celler, har hjernens kapillærer et helt forskjellig endotel: et vegg-til-vegg-teppe, der de endotel cellene er sveiset sammen til en tett
membran. Pga. denne nesten ugjennomtrengelige membranen, er filtreringen fra plasma til vevsvæske betydelig redusert. Bare væske og salter kan passere denne membran.
Membranen er impermeabel for mange små peptider og aminosyrer, og filtratet blir derfor
nærmest proteinfritt. Det sirkulerer gjennom et nettverk av perivaskulære rom til det
blander seg i spinalvæsken. Til sammen utgjør dette ultrafiltrat trolig ca. 10-15 % av
spinalvæsken. I rottehjernen er produksjonen i størrelsesorden 0.25 µ/g hjernevev/min (l). (...)
Antidepressant Use and Risk of Incident Cardiovascular Morbidity and Mortality Among Postmenopausal Women in the Women's Health Initiative Study
Arch Intern Med. 2009;169(22):2128-2139 (Dec 14/28)
(...) Background Antidepressants are commonly prescribed medications, but their effect on cardiovascular morbidity and mortality remains unclear. (...)
Conclusions In postmenopausal women, there were no significant differences between SSRI and TCA use in risk of CHD, stroke, or mortality. Antidepressants were not associated with risk of CHD. Tricyclic antidepressants and SSRIs may be associated with increased risk of mortality, and SSRIs with increased risk of hemorrhagic and fatal stroke, although absolute event risks are low. These findings must be weighed against quality of life and established risks of cardiovascular disease and mortality associated with untreated depression. (...)
Antidepressants May Raise Women's Stroke Risk (Antidepressiva kan øke kvinners risiko for hjerneslag)
minorityhealth.hhs.gov 14.12.2009
(…) It found that women on selective serotonin uptake inhibitors (SSRIs, which include Celexa, Paxil, Prozac and Zoloft) had a 45 percent increase in risk for stroke and a 32 percent increase in risk for death from any cause, compared to non-users. Similar results were found for women on tricyclic antidepressants. (…)
Immune cells cause more post-stroke brain damage: study (Immunceller forårsaker ytterligere hjerneskade etter slag, ifølge studie)
reuters.com 2.8.2009
HONG KONG (Reuters) - Scientists have identified a class of immune cells that floods the brain soon after a stroke, causing inflammation and more neurological damage.
In an experiment, Japanese researchers showed how mice that were deficient in these immune cells suffered far less brain damage after a stroke compared to normal mice.
The lead author of the study, Akihiko Yoshimura at Keio University's School of Medicine in Tokyo, explained that while the initial damage from a stroke cannot be prevented, drugs can be used to limit secondary damage caused by immune cells that rush to the site of the infarction, or stroke.
"The first damage happens immediately after a stroke, we can't block this because it is very rapid," Yoshimura said. (...)
Stroke May Trigger Memory Trouble
healthfinder.gov 10.4.2006
Decline can happen in the absence of other cognitive problems, such as dementia, researchers note
-- Stroke may harm memory without necessarily causing dementia or other cognitive impairment, researchers report.
Columbia University researchers in New York performed an initial assessment of nearly 1,300 people, averaging just over 76 years of age, with no cognitive impairment or dementia. The evaluations were done between January 1992 and December 1994, and the study volunteers were then re-examined at 18-month intervals until November 1999. (...)
Vår renlighet kan orsaka stroke
svt.se 12.2.2010
Allt mer forskning visar idag att vårt sätt att leva i den utvecklade delen av världen kan vara orsaken till många av våra allvarliga sjukdomar. Nu visar svenska forskare att även stroke kan kopplas till brister i immunförsvaret.
Allergier, ms, reumatism, diabetes typ 1 och många andra sjukdomar finns framförallt i den rika delen av världen. Det här är sjukdomar som man idag kopplar till immunförsvaret - eller rättare sagt till problem med immunförsvaret. Vårt immunförsvar överreagerar eller "tänder snett" och slår tillbaka på fel sätt vilket leder till sjukdomar. Och att vårt immunförsvar inte uppför sig som det ska beror troligen på att vi lever så renligt, att vi städar bort bakterier och parasiter från vår omgivning och vår mat.
Nu menar kan alltså svenska forskare vid Karolinska Institutet för första gången visa att även stroke - slaganfall - hänger ihop med brister i immunförsvaret. (...)
Hjärnans immunsystem kan var aktivt vid schizofreni
dagensmedicin.se 19.11.2009
Personer som nyligen insjuknat i schizofreni har förhöjda nivåer av inflammatoriska ämnen i ryggmärgsvätskan. Det visar en studie från Karolinska institutet. (...)
Nu har svenska forskare undersökt ryggmärgsvätska från patienter som nyss insjuknat i schizofreni och jämfört med en kontrollgrupp med friska försökspersoner.
Det visade sig att personerna med schizofreni hade förhöjda nivåer av interleukin-1beta, en signalsubstans som frisätts vid inflammation, i ryggmärgsvätskan. Hos kontrollpersonerna var nivåerna knappt mätbara.
– Det tyder på att hjärnans immunsystem är aktiverat vid schizofreni. Det återstår nu att se om det finns en bakomliggande infektion eller om aktiveringen av immunsystemet uppstår på ett annat sätt, säger Göran Engberg, professor vid Karolinska institutet i Solna, som lett studien.
Den dominerande hypotesen om schizofreni är att hjärnans dopaminsystem är överaktiverat. Det stämmer också överens med det nya fyndet, eftersom interleukin-1beta visat sig rubba dopaminsystemet hos råttor på ett sätt som liknar schizofreni.
De nya fynden väcker hopp om att schizofreni skulle kunna behandlas med läkemedel som påverkar immunsystemet, enligt ett pressmeddelande från Karolinska institutet. (...)
(Anm: Activation of brain interleukin-1 in schizophrenia. Molecular Psychiatry 2009;14:1069–1071.)
Nytt håp i Alzheimer-gåten?
mozon.no 2.2.2007
Dårlig motorikk kan være et tegn på svekket hukommelse hos eldre. Videre forskning kan vise om det har sammenheng med Alzheimers sykdom. (...)
Stroke May Trigger Memory Trouble
healthfinder.gov 10.4.2006
Decline can happen in the absence of other cognitive problems, such as dementia, researchers note
-- Stroke may harm memory without necessarily causing dementia or other cognitive impairment, researchers report.
Columbia University researchers in New York performed an initial assessment of nearly 1,300 people, averaging just over 76 years of age, with no cognitive impairment or dementia. The evaluations were done between January 1992 and December 1994, and the study volunteers were then re-examined at 18-month intervals until November 1999. (...)
Nya forskningsrön kan hjälpa strokepatienter
gp.se 23.2.2006
Uppdaterad: 2006-02-23 22:42
Samma immunsystem som bidrar till skada efter en stroke hjälper också till att reparera skadan. Upptäckten av denna dubbla roll kan på sikt leda till nya sätt att behandla stroke.
Den del av immunförsvaret det handlar om kallas för komplementsystemet. Det består av ett 20-tal proteiner som snabbt aktiveras när kroppen utsätts för fara i form av bakterier, virus eller skada. Komplementsystemet utgör ett slags förtrupper till de mer specificerade cellerna i immunförsvaret.
Nu har forskare vid Sahlgrenska Akademin studerat hur dessa proteiner beter sig på möss som får stroke. Fram tills nu har man ansett att komplementsystemet bidragit till de vävnadsskador man ser efter en stroke, främst genom den inflammation som uppstår. Men nu har docent Marcela Pekna, professor Milos Pekny och deras medarbetare upptäckt att proteinerna är viktiga aktörer också när det gäller att reparera skadorna.
Forskarna upptäckte till sin förvåning att både nervstamceller och omogna nervceller hade mottagare, receptorer, för komplementproteiner på sina ytor. Det visade sig att komplementsystemet spelar en aktiv roll i reparationsarbetet genom att reglera utmognaden av nya nervceller. En hittills helt okänd roll för vårt äldsta immunförsvarssystem.
- När vi tog bort signaleringen genom receptorerna minskade också nybildningen av de reparerande cellerna, säger Marcela Pekna. Det skedde i såväl den normala som i den strokedrabbade hjärnan.
Nu hoppas man kunna använda denna nya kunskap för att så småningom kunna stimulera tillväxt av nya nervceller efter stroke. Men först återstår det mödosamma arbetet att identifiera vilka mekanismer som ligger bakom den här positiva effekten. Det håller man som bäst på med.
- Hittar vi detta finns det goda möjligheter att både utveckla effektiva metoder att begränsa de negativa följderna av immunsvaret och stimulera de mekanismer som skyddar och reparerar nervcellerna, säger Marcela Pekna.
I ett större perspektiv syftar den här typen av forskning till att klarlägga vilka strategier man kan utnyttja för att ersätta skadade eller sjuka nervceller efter sjukdomar som Alzheimer, multipel skleros och stroke eller efter olyckor där nervsystemet skadats.
Senare i år hoppas man komma igång med en undersökning av strokepatienter i Göteborg. Studien presenteras i den ansedda medicintidskriften EMBO Journal, som ges ut av Nature. (...)
- The use of these cognitive enhancing drugs is spreading to younger and younger people. That's a concern.
Cocaine Habit Ages Brain Prematurely (Kokainvaner medfører tidlig aldring av hjernen)
blogs.scientificamerican.com 24.4.2012
Selv om kokain får folk til å føle seg mer oppmerksom og helt på topp i øyeblikket kan det føre til at brukerne opplever at hjernen fungerer dårligere på lengre sikt. En ny studie viser at viktige deler i hjernen ved kronisk bruk i akselererende grad eldes. Resultatene ble publisert online den 24. april i Molecular Psychiatry. (Although cocaine makes people feel more alert and on top of things in the moment, it can leave users vulnerable to a much slower brain in the long run. A new study shows that chronic use ages key parts of the brain at an accelerated rate. The findings were published online April 24 in Molecular Psychiatry.)
Brukere som regelmessig inntar kokain erfarer ofte kognitiv svikt og hjernesvinn (hjerneatrofi), og nye funn viser hvordan disse brukerne faktisk mister grå hjernemasse mye raskere enn de som ikke bruker midlet. (Regular cocaine users often experience early cognitive decline and brain atrophy, and the new findings show how these users are, indeed, actually losing gray matter in their brain much faster than people who don’t take the drug. )
Karen Ersche ved Behavioral and Clinical Neuroscience Institute ved University of Cambridge og medforfatter av den nye studien uttalte at “vi alle mister grå hjernemasse” når vi eldes. Men hun bemerket at “kroniske kokainbrukere mister grå hjernemasse i signifikant raskere grad, hvilket kan være et tegn på for tidlig aldring.” (“As we age we all lose gray matter,” Karen Ersche of the Behavioral and Clinical Neuroscience Institute at the University of Cambridge and co-author of the new study, said in a prepared statement. But, she noted, “chronic cocaine users lose grey matter at a significantly faster rate, which could be a sign of premature aging.”)
Ersche og hennes kolleger brukte magnetresonanstomografi (MRI) for å studere hjernene til 60 mennesker i alderen 18 til 50 år, som brukte kokain jevnlig, og 60 friske mennesker i tilsvarende alder og IQ, som ikke var brukere. De fant at i gjennomsnitt hos friske individer som ikke brukte midlet årlig mistet 1,7 milliliter grå masse, mens kokainbrukere årlig mistet nærmere 3,1 milliliter. (Ersche and her colleagues used magnetic resonance imaging (MRI) to study the brains of 60 people ages 18 to 50 who used cocaine habitually and 60 healthy people of similar ages and IQs who did not. They found that on average, healthy individuals who didn’t use the drug lost about 1.7 milliliters of grey matter annually, whereas cocaine users were losing closer to 3.1 milliliters each year. )
Kokainbrukere mistet mye mer grå masse i prefrontale og temporale regioner—som hjelper å kontrollere hukommelse, beslutningstaking og oppmerksomhet—enn ikkebrukere gjorde. (Cocaine users lost much more gray matter in the prefrontal and temporal regions—which help control memory, decision-making and attention—than non-users did.)
The find brings a new insight into “why the cognitive deficits typically seen in old age have frequently been observed in middle aged chronic users of cocaine,” Ersche said. Even after the researchers excluded the 16 people from the cocaine group who also had alcohol problems, the trend of accelerated brain mass loss held up.
Of the estimated 21 million cocaine users worldwide, about 1.9 million lived in the U.S. as of 2008. And the largest segment of U.S. users were people ages 18 to 25—some 1.5 percent of whom said they had used cocaine in the past month, according to the National Institutes of Health.
“Unge mennesker som bruker kokain trenger informasjon om langtidsrisiko for tidlig aldring,” sier Ersche. Men hun og hennes kolleger bemerket også at resultatene også bør være oppmerksom på de ekstra kognitive vansker som middelaldrende og eldre voksne substansbrukere i stor grad kan ha i tillegg til avhengighetsproblemer. (...) (“Young people taking cocaine today need to be educated about the long-term risk of aging prematurely,” Ersche said. But she and her colleagues also noted that the results also underscore the extra cognitive needs that middle-aged and older adult drug users seem more likely have in addition to their addiction problems.)
(Anm: Cocaine (benzoylmethylecgonine) (INN) is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant.[5] The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is a stimulant of the central nervous system, an appetite suppressant, and a topical anesthetic. Specifically, it is a serotonin–norepinephrine–dopamine reuptake inhibitor (also known as a triple reuptake inhibitor (TRI)), which mediates functionality of these neurotransmitters as an exogenous catecholamine transporter ligand. It is addicting because of the way it affects the mesolimbic reward pathway.[6] (en.wikipedia.org).
(Anm: Hjernesvinn eller hjerneatrofi er et vanlig trekk ved mange av sykdommene som rammer hjernen. Atrofi av ethvert vev betyr tap av celler. I hjernevevet betyr atrofi tap av nerveceller (nevroner) og forbindelsene mellom dem (nervetrådene, aksoner). Atrofien kan være generell og utbredt, hvilket betyr at hele hjernen har skrumpet, eller den kan være avgrenset (fokal) og rammer bare et mindre område av hjernen. Ved et generelt hjernesvinn vil således mange hjernefunksjoner svekkes, mens fokalt hjernesvinn medfører tap av funksjoner som kontrolleres fra dette området av hjernen. Generelt hjernesvinn der begge hjernehalvdelene er skrumpet, kan føre til mental svekkelse og forstyrrelser av aktiviteter som styres av vår vilje. (nhi.no).)
Cocaine dependence: a fast-track for brain ageing?
Molecular Psychiatry , (24 April 2012)
Abstract Cocaine-dependent individuals anecdotally appear aged and their mortality rates are estimated up to eight times higher than in the healthy population.1 Psychological and physiological changes typically associated with old age such as cognitive decline, brain atrophy, or immunodeficiency are also seen in middle-aged cocaine-dependent individuals.2, 3 These observations raise the question of whether cocaine abuse might accelerate the process of normal ageing. Although this is a little-studied area, there are several reasons for assuming that chronic cocaine exposure interferes with the processes of brain ageing. (...)
Decreased dopamine activity predicts relapse in methamphetamine abusers
Molecular Psychiatry , (12 July 2011) | doi:10.1038/mp.2011.86
Abstract Studies in methamphetamine (METH) abusers showed that the decreases in brain dopamine (DA) function might recover with protracted detoxification. However, the extent to which striatal DA function in METH predicts recovery has not been evaluated. Here we assessed whether striatal DA activity in METH abusers is associated with clinical outcomes. Brain DA D2 receptor (D2R) availability was measured with positron emission tomography and [11C]raclopride in 16 METH abusers, both after placebo and after challenge with 60 mg oral methylphenidate (MPH) (to measure DA release) to assess whether it predicted clinical outcomes. For this purpose, METH abusers were tested within 6 months of last METH use and then followed up for 9 months of abstinence. In parallel, 15 healthy controls were tested. METH abusers had lower D2R availability in caudate than in controls. Both METH abusers and controls showed decreased striatal D2R availability after MPH and these decreases were smaller in METH than in controls in left putamen. The six METH abusers who relapsed during the follow-up period had lower D2R availability in dorsal striatum than in controls, and had no D2R changes after MPH challenge. The 10 METH abusers who completed detoxification did not differ from controls neither in striatal D2R availability nor in MPH-induced striatal DA changes. These results provide preliminary evidence that low striatal DA function in METH abusers is associated with a greater likelihood of relapse during treatment. Detection of the extent of DA dysfunction may be helpful in predicting therapeutic outcomes. (...)
TAR ADHD-PILLER FOR Å BLI SMARTERE
dn.no 20.11.2009
Medisiner mot søvnforstyrrelser, Alzheimer og ADHD setter friske menneskers hjerner i høygir. (...)
- Hjernedop kan økonomisere utdanningssystemet
etikkom.no 30.10.2009
(...) Professor John Harris, Universitetet i Manchester, har offentlig tatt til orde for fordelene med bruk av kognitivt forbedrende midler; blant annet i tidsskriftet Nature. Harris åpnet møtet om dette tema i Vitenskapsakademiet i går. Han startet med et sitat av Oscar Wilde. - Å være egoistisk er ikke å leve slik man selv vil, men å få andre til å leve slik en selv vil. Dette var hans utgangspunkt. Hvis hjerneforbedrende midler er sikre nok, hvorfor ikke bruke dem, spurte han ut i salen. (...)
Mer akademisk doping
forskning.no 7.10.2009
Bruk av prestasjonsfremmende narkotiske stoffer øker blant engelske og amerikanske studenter. I Norge finnes det ingen tall på problemet. (...)
- Ritalin bør kunne gis til friske
nrk.no 25.6.2009
- Hvorfor skulle man nekte noen å bli smartere, mer fokusert og mer produktiv? spør professor. – Uhørt, mener Legemiddelverket. (...)
I British Medical Journal (BMJ) tar en professor i bioetikk ved universitetet i Manchester til orde for at også friske mennesker bør få nyte godt av de positive effektene av ADHD-medisiner. (...)
Professoren, som heter John Harris, bruker stoffet metylfenidat som eksempel. Metylfenidat brukes blant annet i Ritalin og kan i noen tilfeller fungere som ”hjernedoping” som forbedrer hjernefunksjonen. (...)
- Trygt betyr alltid trygt nok. Og siden ingen legemidler er uten bivirkninger, betyr det at konsumenten har vurdert risikoen for bivirkninger som verdt å ta, gitt de sannsynlige fordelene. (...)
Forskere vil legalisere «IQ-piller»
aftenposten.no 13.12.2008
Friske mennesker tar spesialmedikamenter for å prestere bedre i akademia. Men dette er ulovlig. Nå går en gruppe anerkjente forskere inn for å legalisere mental doping. (...)
Dette spørsmålet tvinges universitetene i USA nå til å tenke over, etter at det viser seg at på enkelte læresteder har hver fjerde student begynt å bruke medikamentene. I gjennomsnitt bruker 7 prosent av studentene i landet medikamentene, mange av dem uten å ha en ADHD-diagnose. Ritalin inneholder amfetaminlignende stoffer. (...)
På medisinstudentenes utdanningssenter Domus Medica treffer Aftenposten tre legestudenter i 3. og 4. semester. De har hørt om andre studenter som tar ecstasy i eksamensperioder, men aldri om mental doping ved hjelp av de samme legemidlene de selv skal skrive ut om noen år. Marius Dalby, Guro Knutsen og Cecilie Brynestad er svært overrasket over at ekspertgruppen går inn for en legalisering. (...)
(Anm: Ecstasy (MDMA - 3,4-methylenedioxymethamphetamine) (mintankesmie.no).)
Brain boost drugs 'growing trend'
bbc.co.uk 13.10.2008
(...) Increasing numbers of people are using prescription drugs like Ritalin to boost alertness and brain power, say experts.
Up to a fifth of adults, including college students and shift workers, may be using cognitive enhancers, a poll of 1,400 by Nature journal suggests.
Neuropsychologist Professor Barbara Sahakian of Cambridge University said safety evidence is urgently needed.
Experts gather to debate this topic at a meeting in London on Monday evening. (...)
Professor Sahakian said given the increasing use of these drugs outside of their intended clinical setting, safety trials were urgently needed.
"We do not really have long-term efficacy and safety data in healthy people. These are studies that really need to be done.
"The use of these cognitive enhancing drugs is spreading to younger and younger people. That's a concern.
"Methylphenidate does have substantial abusive potential so we have to be worried about substance abuse problems and the use of these drugs in the developing brain in children." (...)
(Anm: The innovative brain. Nature 456, 168-169 (13 November 2008).)
(Anm: Professor's little helper. Nature 450, 1157-1159 (20 December 2007) (mintankesmie.no).)
Skeptisk filosof
aftenposten.no 12.12.2008
(...) - Jeg kan overhodet ikke se hvordan mental doping til friske mennesker vil bidra til et bedre samfunn. Men jeg ser hvordan de vil bidra til et samfunn med dårligere livskvalitet, mener bioetiker Berge Solberg. (...)
Solberg er ikke enig med vurderingene til Harris om at mental doping bør likestilles med utdanning, trening og ernæring. Den norske førsteamanuensen mener denne typen tenking i for stor grad ser utdanning som et rent middel for å nå et mål. (...)
Norsk ekspert gir støtte
aftenposten.no 13.12.2008
- Jeg støtter ekspert-gruppens tanker. Det er veldig vanskelig å komme med gode argumenter for hvorfor slik mental doping skal være forbudt, sier bioetiker Knut G. Berdal.
Berdal leder genmodifiseringsgruppen i Vitenskapskomiteen, men uttaler seg her på selvstendig grunnlag. Han har jobbet med etiske aspekter ved kognitiv forbedring, også kalt mental doping, siden 1995. De siste fire årene har han jobbet spesifikt med dette i Forskningsrådets etikkprogram, og er nå gjesteforsker ved Universitetet i Oxford.
Han vet at de fleste leserne vil oppfatte hans standpunkt som meget kontroversielt. (...)
Ekspertgruppen som står bak artikkelen i Nature påpeker at amerikanske soldater allerede er forpliktet til å ta de samme medikamentene for mental doping under stridsoperasjoner. Ekspertene ser også for seg at legemidlene kan bli så effektive at det kan bli påkrevd at for eksempel kirurger tar dem før risikofylte operasjoner.
Medikamentene er allerede i bruk av leger i USA som tar lange nattevakter. (...)
- Betennelse gir grobunn for kreft
Betennelse gir grobunn for kreft
aftenposten.no 25.10.2010
En celle muterer og utvikler seg til kreft. Denne prosessen er umulig uten at det er en betennelse i kroppen, hevder forfatteren av ny bok.
Det er ikke riktig at økningen i krefttilfeller kun skyldes at folk blir eldre – og dermed sykere. Vi ser jo at også stadig flere barn og unge får kreft. Kreft er blitt en epidemi etter annen verdenskrig, og skyldes først og fremst påvirkninger fra miljøet og maten vi spiser, mener den fransk–amerikanske legen og hjerneforskeren David Servan–Schreiber.
Hans siste bok, Kreft & terrenget ditt, er nå oversatt til norsk, og vil trolig skape debatt også i Norge. For etter å ha saumfart kreftstudier og forskingsresultater fra hele verden gjennom en årrekke, konkluderer Servan–Schreiber: Kreft oppstår fordi en celle muterer som følge av ytre påvirkning og livsstil. Men det er ditt eget, indre «terreng» som gjør kreftcellene i stand til å utvikle seg til en alvorlig sykdom.
Akutt eller kronisk
I følge Servan–Schreiber er en betennelse i kroppen en forutsetning for at kreft kan utvikle seg. Betennelsen kan være akutt og hissig, eller den kan være nesten umerkelig skjult eller kronisk. Forårsaket av et virus eller en bakterie – eller av en autoimmun sykdom der kroppen selv skaper inflammasjonen.
Nyere forskning har også satt flere kreftformer – for eksempel livmorkreft, i direkte sammenheng med spesielle virus. Kreft kan oppstå et sted på kroppen der det tidligere har vært en skade eller et sår som de hvite blodlegemene og immunapparatet har forsøkt å reparere. (...)
- Vi ser det blant annet ved leverkreft, tykktarmskreft og B–cellelymfom. Også autoimmune sykdommer kan trigge frem en kreftutvikling, sier Krokan. (...)
Også Rune Blomhoff, professor i ernæringsfysiologi ved Universitetet i Oslo, bekrefter at betennelse har svært stort fokus i hans forskergruppe. Men hva er høna og hva er egget, spør han. For kreft skaper jo også en betennelse i kroppen når den har oppstått, og det er ikke lett å skille betydningen av betennelse som en årsak til kreft – og som et resultat av kreft, sier han. (...)
(Anm: Kreft & terrenget ditt - hva kan du selv gjøre. David Servan-Screiber (bokkilden.no).)
Allergi mindsker risiko for kræft
bt.dk 24.5.2010
Pollensæsonen kan være et mareridt for allergikere og astmatikere, men nys og røde øjne er faktisk godt for noget.
Børn med pollenallergi har nemlig 40 procent mindre risiko for leukemi, mens folk med astma har 30 procent mindre risiko for kræft i æggestokkene. (...)
Flere undersøgelser har gennem de seneste år vist, at allergier og astma skulle have en beskyttende effekt mod kræft. Blandt andet har engelske forskere fundet frem til, at der var mindre risiko for lymfeknuder og kræft i mavesækken, mens nogle forskere fra Harvard ligeledes fandt en sammenhæng mellem en mindre risiko for kræft i hjernen, hvis man havde astma, høfeber eller allergi.
Læger fra Toronto mener, at risikoen for at få kræft i bugspytskirtlen mindskes med op mod 58 procent, hvis man lider af allergi eller høfeber.
Flere eksperter mener, at immunsystemet er langt mere avanceret hos allergikere. Det kan skyldes, at når de nyser, får de nyst forskellige giftstoffer ud af systemet. (...)
Värktabletter kan skydda mot Parkinson
aftonbladet.se 30.3.2010
(...) Analysen visade att normal användning av värktabletter med ibuprofen kunde kopplas till 15 procent lägre risk att drabbas av Parkinson. (...)
Funkade inte med paracetamol
Ett sådant samband gick inte att se när forskarna tittade på andra värktabletter med acetylsalicyra eller paracetamol. Enligt forskarna stödjer det teorin om att nervcellsinflammation är en del i sjukdomsförloppet bakom Parkinsons sjukdom. (...)
New study highlights immune system's role in Alzheimer's (Ny studie fremhever immunsystemets rolle i Alzheimers sykdom)
pharmanews.eu 26.3.2010
The brain's immune cells may be behind the loss of neurons associated with Alzheimer's disease, new EU-funded research suggests. The findings, published in the journal Nature Neuroscience, could lead to the development of new treatments for the neurodegenerative disease. (...)
Strålning mot cancer påverkar gener - ger åderförkalkning senare i livet
sverigesradio.se 29.3.2010
Människor som fått strålbehandling mot cancer löper ökad risk att drabbas av hjärt- och kärlsjukdom senare i livet. En ny forskningsstudie visar att det beror på att strålningen gör att gener i blodkärlen ger upphov till inflammation.
Strålning påverkar gener som skadar blodkärl
sverigesradio.se 29.3.2010
– Jag tycker att det här är en väldigt intressant artikel, eftersom den på ett elegant sätt ger en förklaring till ett kliniskt fenomen som vi har sett under många år. Det säger docent Stefan James som har läst den nya studien. Han arbetar på kardiologkliniken på Akademiska sjukhuset i Uppsala. (...)
- Brain Scans of Pain Raise Questions for the Law
Brain Scans of Pain Raise Questions for the Law (Hjerneskanninger av smerte reiser lovspørsmål)
Science 2009;323(5911):195 (January 2009)
Neuroimaging is knocking on the courthouse door. But although certain brain regions consistently rev up when people experience pain, neuroscientists have yet to demonstrate that the converse is true: that any particular pattern of brain activity necessarily indicates the presence of pain. (...)
- Brain imaging studies under fire
Brain imaging studies under fire
Nature 2009;457:245 (13 January)
Social neuroscientists criticized for exaggerating links between brain activity and emotions.
A study attacking some of the most prominent research in the burgeoning field of social neuroscience is flawed and unfair, according to top scientists who have been accused of overselling their results.
Social neuroscience is the study of the neurobiological mechanisms underlying social behaviour. The field frequently uses functional magnetic resonance imaging (fMRI) to reveal which brain areas are activated while a subject is exposed to specific social interactions — for example, situations that may evoke jealousy or the perception of unfairness.
But a no-holds-barred paper1, accepted for publication in Perspectives on Psychological Science and already circulating widely on the Internet, claims that many studies in the field are worthless because brain imaging data have been poorly analysed.
The paper was written by Edward Vul, a PhD student supervised by neuroscientist Nancy Kanwisher at the Massachusetts Institute of Technology in Cambridge, along with psychologists at the University of California, San Diego, including Harold Pashler. (...)
- Hjerneskanninger avslører hemmeligheter bak "skrivekrampe"
Brain Scans Reveal Secrets of 'Writer's Cramp' (Hjerneskanninger avslører hemmeligheter bak "skrivekrampe")
healthfinder.gov 15.4.2009
Condition may arise from abnormalities in nerve fiber bundles, scientists say.
(SOURCES: Stephane Lehericy, M.D., Ph.D., director, Center for NeuroImaging Research, and professor, department of neuroradiology, Pitie-Salpetriere Hospital, Paris; Daniel Labovitz, M.D., director, division of cerebral vascular disease, New York University Langone Medical Center, and assistant professor, neurology, NYU School of Medicine, New York City; April 2009 Archives of Neurology)
WEDNESDAY, April 15 (HealthDay News) -- A team of French researchers has linked abnormalities in certain neural pathways of the brain to the debilitating muscle disorder known as "writer's cramp."
The finding could lead to a better understanding of the neurological basis for the resulting loss of muscle control and coordination that characterizes this difficult-to-diagnose disorder -- also known as "hand dystonia." The condition can render a patient unable to write or even maintain a functional grip when trying to perform a simple task.
"These results demonstrate the presence of abnormalities in [brain] fiber tracts," that are located in areas known to be involved with writer's cramp, said study author Dr. Stephane Lehericy, director of the Center for NeuroImaging Research at Pitie-Salpetriere Hospital in Paris.
Lehericy explained that although prior research had already linked writer's cramp to problematic alterations in the gray matter in certain brain regions, the current investigation identified problems with the white matter of certain nerve pathways in brain areas that are responsible for generating motor commands.
Such white matter, explained Lehericy, "contains fiber bundles that convey information from one brain region to another, as well as to the spinal cord."
Lehericy and his team reported the findings in the April issue of the Archives of Neurology.
To explore linkages between the disorder and the brain, the French team conducted high-tech diffusion-tenor magnetic resonance imaging (DTI) to scan for brain abnormalities among 26 right-handed writer's cramp patients and 26 right-handed healthy participants.
Among the writers cramp patients, the scans uncovered structural abnormalities in the white matter from the primary sensorimotor cortex region of the brain to below-cortex regions such as the thalamus. The observed abnormalities were not present among the healthy participants.
Such connections, the researchers noted, are typically key to the proper transference of motor coordination instructions from the brain to the spine, brain guidance that ultimately enables proper limb movement.
Dr. Daniel Labovitz, director of the division of cerebral vascular disease at New York University's Langone Medical Center, said the French researchers used "a very interesting technique to look at a very interesting problem."
"This is a solid piece of work," he said, "and a fascinating area of research that touches on issues that go far beyond writer's cramp alone and has to do with a whole range of activity-related difficulties that clearly have to do with a problem with the brain."
"So this study builds on the little knowledge we have on an exceedingly rare and unusual issue for which we have virtually no treatment," Labovitz added. "No, this finding doesn't tell us what the brain changes mean exactly. But it does add incrementally and importantly to our understanding of the neurology underlying the problem."
More information
For more on writer's cramp, head to the Dystonia Medical Research Foundation (...)
(Anm: dystonia; dystoni; endring i muskulaturens spenningstilstand, ofte i form av ufrivillige muskelsammentrekninger (f.eks. i nakkemuskulaturen og svelgmuskulaturen. Dystoni kan være symptom ved indremedisinske og nevrologiske sykdommer, men kan også opptre som bivirkning av legemidler som blokkerer signalsubstansen dopamin. Akutte dystonier sees hos yngre menn noen dager etter at vedkommende har begynt på relativt høye doser med nevroleptika. (...) Ved akutte dystonier på grunn av legemidler er behandlingen tilførsel av antiparkinsonmidler. Kilde: Store norske leksikon.)
- Underlig atferd på Ambian linket til hjernekretser
Odd Behaviors on Ambien Linked to Brain Circuitry (Underlig atferd på Ambian linket til hjernekretser)
healthfinder.gov 4.7.2009
When the sleep aid shuts down one set of neurons, another set wakes up, study contends.
THURSDAY, July 2 (HealthDay News) -- New information about brain circuit activity may help explain why some people who take the sleep aid Ambien (zolpidem) walk, eat, talk on the phone and even drive while not fully awake -- and without remembering it the next morning.
The drug has also been shown to awaken minimally conscious patients into a conscious state.
In experiments with mice, researchers at Georgetown University Medical Center in Washington, D.C., found that zolpidem shuts down some powerful brain circuits but activates other circuits when they're deprived of activity.
"Brain cells or neurons are highly reactive to incoming activity throughout life," study corresponding author Molly M. Huntsman, an assistant professor in the department of pharmacology, said in a news release.
"When brain activity is silenced, many neurons automatically react to this change. We see this in our study, which suggests that inhibitory neurons responsible for stopping neural activity are themselves shut down by zolpidem. The excitatory neurons, responsible for transmitting activity, are then allowed to re-awaken and become active again, without monitoring, because the inhibitory neurons are 'asleep'," she explained.
While it appears that zolpidem shuts down active neural pathways and perhaps triggers activity in others, the actual mechanism isn't known.
"Nevertheless, the paradoxical activation of brain circuits by a powerful sedative definitely needs more attention in additional studies in both human and animal models," Huntsman said.
The study was published in this week's Proceedings of the National Academy of Sciences journal. (...)
(Anm: Ambian (zolpidem); Handelsnavn for zolpidem inkluderer Adormix, Ambien, Ambien CR, Edluar, Damixan, Hypnogen, Ivedal, Nytamel, Stilnoct, Stilnox, Sucedal, Zoldem, Zolnod and Zolpihexal. (en.wikipedia.org).)
Study in mice sheds light on Ambien side effects (Studie på mus kaster lys over Ambian sideeffekter)
reuters.com 29.6.2009
CHICAGO (Reuters) - A new study in mice may help explain some of the rare but strange side effects in people taking the sleep drug Ambien, including sleep walking, midnight binges and even driving while not fully awake.
Ambien, made by Sanofi-Aventis, can shut down powerful brain circuits responsible for inhibiting brain activity under certain circumstances, leaving other brain circuits unchecked, researchers at Georgetown University Medical Center in Washington said.
"You are kind of releasing the brakes," said Molly Huntsman of Georgetown, who worked on the study that appears in the Proceedings of the National Academy of Sciences.
This may stimulate brain circuits that would normally be silenced. "In a way, Ambien is awakening other circuits because the brakes are not in place," Huntsman said.
To study the effects of the drug, known generically as zolpidem, Huntsman and colleagues conducted a series of experiments in mice. (...)
(Anm: Ambian (zolpidem); Handelsnavn for zolpidem inkluderer Adormix, Ambien, Ambien CR, Edluar, Damixan, Hypnogen, Ivedal, Nytamel, Stilnoct, Stilnox, Sucedal, Zoldem, Zolnod and Zolpihexal. (en.wikipedia.org).)
- Stiller spørsmål ved "nevrobeskyttende" hypotese: forebygger legemiddelbehandling hjerneskade i tidlig psykose eller skizofreni?
Questioning the ‘neuroprotective’ hypothesis: does drug treatment prevent brain damage in early psychosis or schizophrenia? (Stiller spørsmål ved "nevrobeskyttende" hypotese: forebygger legemiddelbehandling hjerneskade i tidlig psykose eller skizofreni?)
Editorials
The British Journal of Psychiatry (2011) 198: 85-87
The idea that psychotic disorders are characterised by progressive neurodegeneration that can be reversed by drug treatment is used to justify early treatment of increasing numbers of mostly young people. I argue that there is little evidence to support the view that old- or new-generation antipsychotics are ‘neuroprotective’, and some evidence that the drugs themselves may be responsible for the decline in brain matter observed in some studies. (...)
- Antipsykotika og hjernevolum (Trenger vi å være bekymret?)
Antipsychotic Medications and Brain Volume (Antipsykotika og hjernevolum)
Arch Gen Psychiatry. 2011;68(2):126-127 (February)
Do We Have Cause for Concern? (Trenger vi å være bekymret?)
Since the initiation of antipsychotic drug therapy for schizophrenia, clinical observations and empirical studies have demonstrated that these medications bring benefit and harm. Consequently, efforts to develop new antipsychotic medications during the past 50 years have been motivated, at least partly, by the desire to enhance the benefit to harm ratio relative to existing medications. In this issue of the Archives, Ho and colleagues1 examine one arm of this ratio by asking whether antipsychotic medications contribute to progressive brain volume reductions in schizophrenia. Individuals early in the course of schizophrenia (n = 211) were treated with antipsychotic medications according to standard clinical practice and followed up longitudinally with clinical assessments and serial magnetic resonance imaging (MRI) scans (between 2 and 5 scans per individual) for a mean of 7 years. The authors found that the amount of exposure to antipsychotic medication predicted decrements in cerebral gray and white matter volumes and increased the volume of the putamen. Illness duration and severity were also associated with smaller brain volume measures, but the relationship between antipsychotic medication use and brain volume remained significant after accounting for the effects of illness severity and duration and substance abuse history. Interestingly, changes in brain volume with time were similar for all classes of antipsychotic medications (ie, typical antipsychotics, atypical [ie, excluding clozapine] antipsychotics, and clozapine). (...)
- Här får du ett medel och dina personlighetsdrag kommer att förändras
Antidepressants Make Shrimps See the Light (Antidepressiva får reker til å se lyset)
sciencedaily.com 12.7.2010
ScienceDaily (July 12, 2010) — Rising levels of antidepressants in coastal waters could change sea-life behaviour and potentially damage the food-chain, according to a new study. (...)
Research into the behaviour of shrimps exposed to the antidepressant fluoxetine, showed that their behaviour is dramatically affected. The shrimps are five times more likely to swim toward the light instead of away from it -- making them more likely to be eaten by fish or birds, which could have devastating effects on the shrimp population. (...)
Dr Ford's research was motivated by a species of parasite which can alter the behaviour of aquatic creatures through changing serotonin levels within the brains of the organisms. Serotonin is a neuro-hormone found in many animals, including humans, known to control types of behaviour, such as modulating mood and decreasing anxiety.
Drugs to combat depression in humans are often designed to target levels of serotonin which led to the question of whether they could also alter the behaviour of marine organisms.
Dr Ford said: "Effluent is concentrated in river estuaries and coastal areas, which is where shrimps and other marine life live -- this means that the shrimps are taking on the excreted drugs of whole towns." (...)
(Anm: Anti-depressants make amphipods see the light. Aquatic Toxicology 2010 (Jun 4).)
Prozac Pollution Making Shrimp Reckless (Prozac forurensning gjør reker likeglad)
news.nationalgeographic.com 17.6.2010
Antidepressant's key ingredient is flushed into coastal waters, study says.
There's no happy ending for shrimp exposed to the mood-booster Prozac, according to a new study.
Remnants of antidepressant drugs flushed into waterways worldwide are altering shrimp behavior and making them easier prey, experts say.
(See "Cocaine, Spices, Hormones Found in Drinking Water.")
To mimic conditions in the wild, scientists exposed the estuary-dwelling shrimp Echinogammarus marinus to the antidepressant fluoxetine at levels detected in average sewage-treatment waste. Fluoxetine is the key ingredient in the drugs Prozac and Sarafem.
Shrimp normally gravitate toward safe, dark corners. But when exposed to fluoxetine, the animals were five times more likely to swim toward a bright region of water, the team discovered.
"This behavior makes them much more likely to be eaten by a predator, such as a fish or bird," said study co-author Alex Ford, a biologist at U.K.'s University of Portsmouth.
The fluoxetine likely makes shrimp's nerves more sensitive to serotonin, a brain chemical known to alter moods and sleep patterns, according to the study, recently published in the journal Aquatic Toxicology. (...)
Medicin ändrar personligheten
sr.se 8.12.2009
En typ av antidepressiva medel, så kallade SSRI preparat, ger en personlighetsförändring. Det handlar om minskad ängslighet. Det visar en mindre amerikansk studie på totalt 240 personer. (...)
Elias Eriksson som är professor i farmakologi vid i Göteborg. Han menar att problemet är att SSRI preparat först lanserades som antidepressiva läkemedel, även om de inte har störst effekt där. De ska absolut inte ska användas för personer som är ledsna:
– Om man är ledsen av yttre orsaker bör man inte äta sådant här. Det tror jag är ett av de vanligaste felen till överförskrivning, det är att man skriver ut det här till personer som varken har någon depressions sjukdom eller något ångesttillstånd utan som har en nedstämdhet orsakad av yttre omständigheter. Då ska man inte förskriva de här medlen. Däremot vid depression eller ångettillstånd bör de användas.
Men kan du förstå då om det kan låta obehagligt för personer att höra "här får du ett medel och dina personlighetsdrag kommer att förändras"? (...)
(Anm: personlighetsendring; varig endring i en persons måte å tenke, reagere og være på i personlige og sosiale situasjoner (jfr. personlighet). (…)
Årsaker - Personlighetsendring kan være forårsaket av legemlige sykdommer eller skader som rammer hjernen (bl.a. organisk betingede psykiske lidelser som f.eks. demens), skyldes langvarig misbruk av stoff eller andre rusmidler (f.eks. alkohol), eller forekomme som en del av utviklingen av en alvorlig psykisk lidelse som f.eks. schizofreni. Tilstander som kan minne om varig personlighetsendring, finnes også hos psykologisk sett selvusikre, søkende individer som på jakt etter klare verdier og med behov for å tilhøre et fellesskap trekkes inn i enkelte ekstreme religiøse bevegelser. Kilde: Store norske leksikon.)
(Anm: SSRI-utløst aggresjon? (mintankesmie.no).)
Antidepressiva kan endre din personlighet
nrk.no 7.12.2009
Ifølge en studie utført på vegne av det amerikanske helsevesenet kan medisiner med virkestoffet Paroxetine gjøre folk både mindre nevrotiske og mer utadvendte, skriver Reuters.
Paroxetine finnes i blant annet Paroxat, Paroxetin og Seroxat, som selges som reseptbelagte midler i Norge. (...)
- Det er en dramatisk forskjell, sier Tang, og forklarer at man tidligere har trodd at endring i personligheten kom fordi man fikk depresjonen mer under kontroll. (...)
- Alzheimers sykdom: Besøk øyelege for å oppdage det tidlig
Alzheimer's: Visit Eye Doctor to Catch it Early (Alzheimers sykdom: Besøk øyelege for å ta fatt i det tidlig)
Ivanhoe.com 22.2.2010
(Ivanhoe Newswire) -- A new study gives seniors a reason to visit the ophthalmologist -- those with poor vision who sought help were 64 percent less likely to develop dementia.
University of Michigan researchers suggest poor vision may now be a predictor of dementia and not just a symptom that comes after diagnosis. They looked at Medicare data relating to poor vision, visits to the ophthalmologist and a national study.
“Our results indicate that it is important for elderly individuals with visual problems to seek medical attention so that the causes of the problems can be identified and treated," Mary A.M. Rogers, Ph.D., research assistant professor of internal medicine at the University of Michigan Medical School and research director of the Patient Safety Enhancement Program at the University of Michigan Health System and the Ann Arbor VA Medical Center, was quoted as saying. (...)
- Blir ruset av sukker
- Sukker og fett gir nesten like sterkt sug som narkotika
aftenposten.no 31.10.2011
Blandingen av sukker og fett, som i et skolebrød, kan gi sterk avhengighet, mener forsker. Sultne mus viste henne dette ved en ren tilfeldighet.
- Vi skulle undersøke narko-avhengighet og brukte mus for å teste våre hypoteser. Kontrollgruppen besto av mus som fikk mat - vi tenkte at det ville gi et nøytralt svar, forklarer professor Sara Ward ved Templeuniversitetet i Philadelphia.
Men slik var det ikke.
Forskerne oppdaget at søt og fet mat også skapte sterk avhengighet. Dette rotet til forskningsopplegget, men var samtidig så interessant at forskerne presenterer funnene.
Musetesten
- Musene var nesten like interessert i søt og fet mat som av kokain, sammenfatter Sara Ward.
Musene måtte dytte nesen mot en luke for å få tilgang til mat og drikke. Normalt sultne mus dyttet maksimalt ti ganger. Men om de hadde lært seg at luken ga tilgang til sukkervann - omtrent som vanlig brus - dyttet de på luken 44 ganger.
Det samme med fett: Når musene hadde lært at en luke ga tilgang til fett, dyttet de på luken 50 ganger før de ga opp. (...)
Blir ruset av sukker
aftenposten.no 10.11.2009
Forskere ser nå en sammenheng mellom alle former for rus – fra heroin til sukker. Avansert hjerneskanning kan finne fellesnevneren.
Kan noen mennesker bli så hektet på sukker at det kan sammenlignes med en rusavhengighet? Ja, svarer en av tungvekterne i amerikansk helsepolitikk, David A. Kessler.
Kessler, som blant annet har vært sjef for det amerikanske legemiddelverket – Food and Drug Administration – har vakt oppsikt i USA med sin siste bok The end of overeating. Der setter han søkelyset på matvareindustrien og den amerikanske overspisingen, og viser hvordan matvareprodusentene kynisk tilsetter ingredienser som fettstoffer, salt, stimulerende smaksforsterkere – eller sukker – i en mat designet nettopp for å hekte oss på kroken. (...)
Professor Kathleen Brady, avhengighetsforsker ved Medical University i Sør-Carolina, forklarer det slik: Det som skjer når en person utvikler et usunt avhengighetsforhold, er at dopaminsystemet har problemer med å tilføre hjernen nok dopamin. Dette gjør at man ikke klarer å føle glede og tilfredsstillelse på en normal måte. (...)
Lika beroendeframkallande som heroin
mobil.svt.se 26.3.2010
För första gången kan forskare nu visa att mat, eller närmare bestämt det vi brukar kalla skräpmat, kan skapa samma typ av fysiska beroende som kokain och heroin. Samma biokemiska mekanismer som får vissa att falla in i missbruk av tunga droger förklarar också varför andra äter sig feta.
Att äta trots att man inte borde. Att stoppa i sig godis, chips, cocacola mm fast man vet att det är skräp och att det ökar på midjemåttet. Varför gör vissa det och varför är det så svårt att sluta? Handlar det om dålig karaktär, eller finns det andra, mer djuplodande förklaringar till att vissa blir feta.
Nu kan forskare från The Scripps Research Instituet i USA för första gången visa att matberoende i vissa fall kan vara lika svårt att sluta med som droger. (...)
Råttorna utsattes även för elektriska stötar när de åt skräpmat, men trots det obehaget valde råttorna ändå att fortsätta att äta. (...)
Diverse artikler
Do Psychedelics Expand the Mind by Reducing Brain Activity?
scientificamerican.com 15.5.2012
New evidence suggests drugs like LSD open the doors of perception by inhibiting parts of the brain
What would you see if you could look inside a hallucinating brain? Despite decades of scientific investigation, we still lack a clear understanding of how hallucinogenic drugs such as LSD (lysergic acid diethylamide), mescaline, and psilocybin (the main active ingredient in magic mushrooms) work in the brain. Modern science has demonstrated that hallucinogens activate receptors for serotonin, one of the brain’s key chemical messengers. Specifically, of the 15 different serotonin receptors, the 2A subtype (5-HT2A), seems to be the one that produces profound alterations of thought and perception. It is uncertain, however, why activation of the 5-HT2A receptor by hallucinogens produces psychedelic effects, but many scientists believe that the effects are linked to increases in brain activity. Although it is not known why this activation would lead to profound alterations of consciousness, one speculation is that an increase in the spontaneous firing of certain types of brain cells leads to altered sensory and perceptual processing, uncontrolled memory retrieval, and the projection of mental “noise” into the mind’s eye. (...)
The study in question was conducted by Dr. Robin Carhart-Harris in conjunction with Professor David Nutt, a psychiatrist who was formerly a scientific advisor to the UK government on drugs policy. Drs. Carhart-Harris, Nutt, and colleagues used functional magnetic resonance imaging (fMRI) to study the effects of psilocybin on brain activity in 30 experienced hallucinogen users. In this study, intravenous administration of 2 mg of psilocybin induced a moderately intense psychedelic state that was associated with reductions of neuronal activity in brain regions such as the medial prefrontal cortex (mPFC) and the anterior cingulate cortex (ACC). (...)
The findings reported by Dr. Carhart-Harris are notable because they run counter to the results of previous imaging studies with hallucinogens. Generally, these imaging studies in humans have confirmed what previous studies in animals had suggested: hallucinogens act by increasing the activity of certain types of cells in multiple brain regions, rather than by decreasing activity as indicated by Dr. Nutt’s fMRI study. For example, Positron Emission Tomography (PET) experiments conducted by Dr. Franz Vollenweider in Zürich demonstrated that administration of psilocybin orally to humans increases metabolic activity in mPFC and ACC, effects that were found to be directly correlated with the intensity of the psychedelic response. Preclinical studies, using a variety of different techniques, have shown that hallucinogens increase network activity in the prefrontal cortex and in other cortical regions by activating excitatory and inhibitory neurons, leading to increased release of excitatory and inhibitory neurotransmitters. (...)
Understanding Psychopathic and Sadistic Minds
healthland.time.com 14.5.2012 (Time)
The fictional character Hannibal Lecter
Psychopathic serial killers are a source of infinite public fascination. If best-selling novels, hit TV series and popular films are any indication, you’d think real-life Hannibal Lecters were constantly running amok in the U.S. Thankfully, such offenders are far less prevalent in reality than they are in entertainment — but the disproportionate damage done by violent and even nonviolent psychopaths not surprisingly attracts intense scientific interest as well. On May 11, in fact, the New York Times explored whether psychopaths can be diagnosed as young as age 9.
Another way to figure out what makes the psychopath tick is to contrast him — and they are overwhelmingly male — with other abnormal personalities. In a recent study led by Jean Decety, a professor of psychology and psychiatry at the University of Chicago, researchers looked at a personality trait often confused with psychopathy: sexual sadism. (...)
Gene Linked to Increased Risk of PTSD
scientificamerican.com 14.5.2012
Variations in the PKCA gene and reports of emotionally affecting photos among 700 health young volunteers confirm hypotheses about the core role of memory in PTSD
European researchers have identified a gene that is linked to improved memory, but also to increased risk of post-traumatic stress disorder (PTSD).
Dominique de Quervain of the University of Basel in Switzerland and his colleagues recruited around 700 healthy young volunteers, obtaining DNA samples from them to analyze the sequence of their PRKCA gene. This gene is one of many known to be involved in the formation of emotional memories, and encodes an enzyme called protein kinase C-?. The researchers then showed the participants a series of emotionally affecting photographs and shortly afterwards asked them to write down short descriptions of the images.
Participants carrying two copies of one variant within the PRKCA gene, dubbed the A allele, remembered the most details about the pictures. Those carrying two copies of the other variant -- the G allele -- remembered the least, with the performance of those carrying one copy of each variant lying somewhere in the middle. (...)
En sosialmedisinsk diagnose
aftenposten.no 9.5.2012
Skal vi snart komme til saken nå? Som er at det 22. juli 2011 ble begått et politisk attentat i Norge.
«Nå synes jeg ikke denne saken er morsom lenger», sa en finere dame i et selskap forleden. Behring Breivik-saken underholder ikke lenger. Kjedsomheten brer seg. (...)
Savnet fellesskap
«There is no such thing as a society», ropte Margaret Thatcher. Høyrepartiene er på fremmarsj også i Norge. Fellesskapene våre forvitrer. Men mennesket trenger å være trygg i flokk. Marcel Proust har rett: «The question is not as for Hamlet to be or not to be, but to belong or not to belong». Behring Breivik lengtet etter en flokk å høre til i. Han fant de hvite ridderne.
De siste tiårene har Jeget kolonialisert mer og mer av mennesket. Du er din egen byggmester og lykkesmed. Slik ble Behring Breivik et 1-tall, alene på gutterommet, alene i cyberspace. Det eksistensielle bevis er å bli sett: Jeg er i medielys, derfor er jeg. Den unge greske guden Narcissos forelsket seg i sitt eget speilbilde i et stille vann. Behring Breivik lengtet etter sitt bilde på alle forsider og TV-skjermer. Da han ble avvist av en kjendis på et utested i Oslo i 2010, sa han omtrent: Bare vent - om et år er jeg mye mer kjent enn deg. (...)
Annen hjernestruktur hos psykopater
dagensmedisin.no 9.5.2012
Britiske forskere har ved hjelp av MRI-bilder avdekket at kriminelle psykopater med antisosial personlighetsforstyrrelser har en annen hjernestruktur enn folk flest.
Forskere ved King’s College London’s Institute of Psychiatry har undersøkt hjernen til menn som har begått mord, voldtekt og andre voldshandlinger.
Av de 44 mennene som gjennomgikk MRI-skanning, oppfylte 17 av dem diagnosen for antisosial personlighetsforstyrrelse og psykopati.
Forskerne skannet også hjernen til 22 friske ikke-kriminelle. (...)
Ifølge resultatene fra de britiske forskernes studie, bestod psykopatenes hjerne av signifikant mindre grå substans i fremre deler av prefrontale korteks og i temporallpolene (spissen av temporallappen).
Dette er områder i hjernen som er viktige for å forstå andre menneskers følelser og er aktivert i forbindelse med refleksjoner omkring moral.
Skader i disse områdene er ifølge forskerne koblet til mangel på empati, dårlig respons i forhold til frykt og stress og mangel på følelser som skyld og skam, skriver Reuters Health. (...)
The Antisocial Brain: Psychopathy Matters
Arch Gen Psychiatry. 2012 (Published online May 7)
A Structural MRI Investigation of Antisocial Male Violent Offenders
Context The population of men who display persistent antisocial and violent behavior is heterogeneous. Callous-unemotional traits in childhood and psychopathic traits in adulthood characterize a distinct subgroup.
Objective To identify structural gray matter (GM) differences between persistent violent offenders who meet criteria for antisocial personality disorder and the syndrome of psychopathy (ASPD+P) and those meeting criteria only for ASPD (ASPD–P).
Design Cross-sectional case-control structural magnetic resonance imaging study.
Setting Inner-city probation services and neuroimaging research unit in London, England.
Participants Sixty-six men, including 17 violent offenders with ASPD+P, 27 violent offenders with ASPD–P, and 22 healthy nonoffenders participated in the study. Forensic clinicians assessed participants using the Structured Clinical Interview for DSM-IV and the Psychopathy Checklist–Revised.
Main Outcome Measures Gray matter volumes as assessed by structural magnetic resonance imaging and volumetric voxel-based morphometry analyses.
Results Offenders with ASPD+P displayed significantly reduced GM volumes bilaterally in the anterior rostral prefrontal cortex (Brodmann area 10) and temporal poles (Brodmann area 20/38) relative to offenders with ASPD–P and nonoffenders. These reductions were not attributable to substance use disorders. Offenders with ASPD–P exhibited GM volumes similar to the nonoffenders.
Conclusions Reduced GM volume within areas implicated in empathic processing, moral reasoning, and processing of prosocial emotions such as guilt and embarrassment may contribute to the profound abnormalities of social behavior observed in psychopathy. Evidence of robust structural brain differences between persistently violent men with and without psychopathy adds to the evidence that psychopathy represents a distinct phenotype. This knowledge may facilitate research into the etiology of persistent violent behavior. (...)
Study finds psychopaths have distinct brain structure
reuters.com 7.5.2012
(Reuters) - Scientists who scanned the brains of men convicted of murder, rape and violent assaults have found the strongest evidence yet that psychopaths have structural abnormalities in their brains.
The researchers, based at King's College London's Institute of Psychiatry, said the differences in psychopaths' brains mark them out even from other violent criminals with anti-social personality disorders (ASPD), and from healthy non-offenders.
Nigel Blackwood, who led the study, said the ability to use brain scans to identify and diagnose this sub-group of violent criminals has important implications for treatment.
The study showed that psychopaths, who are characterized by a lack of empathy, had less grey matter in the areas of the brain important for understanding other peoples' emotions.
While cognitive and behavioral treatments may benefit people with anti-social personality disorders, the same approach may not work for psychopaths with brain damage, Blackwood said.
"To get a clear idea of which treatments are working, you've got to clearly define what people are like going into the treatment programs," he said in a telephone interview.
Essi Viding a professor in the psychology and language sciences department of University College London, who was not involved in Blackwood's study, said it provided "weighty new evidence" about the importance of distinguishing psychopathic from non-psychopathic people rather than grouping them together. (...)
Norsk forsker har påvist hjernesvinn hos nordsjødykkere
tv2nyhetene.no 7.5.2012
HJERNESVINN: I en ny studie har overlege Gunnar Moen påvist at tidligere nordsjødykkere har tapt hjernevev.
Ny norsk studie viser at tidligere nordsjødykkere har signifikant tap av hjernevev.
Overlege Gunnar Moen ved Radiologisk avdeling ved Haukeland universitetssykehus har nylig avsluttet en ny studie av helsetilstanden til tidligere nordsjødykkere.
I studien har han oppdaget at nordsjødykkerne har signifikant tap av hjernevev eller nerveceller.
– Vi tok MR av hjernen deres og det vi så etter var om det var noen strukturelle endringer i hjernen deres, altså tap av hjernevev, sier Moen til tv2.no.
Overlegen forklarer at det dreier seg om såkalt grå substans. Det er den delen av hjernen og ryggmargen hvor nervecellene befinner seg.
Overlegen forklarer at det dreier seg om såkalt grå substans. Det er den delen av hjernen og ryggmargen hvor nervecellene befinner seg.
Les også: Nordsjødykkerne til Høyesterett
– Det vi ser er at de har signifikant tap av hjernevev, sier Moen.
Resultatene fra denne studien er ikke publisert enda, men vil trolig komme i løpet av sommeren. (...)
– Dykkerne har fått varig nedsatt blodsirkulasjon i flere områder av hjernen og varige endringer av hjernens mikrostruktur (cellemembraner). Lignende har aldri vært påvist tidligere, sier overlege Gunnar Moen.
Studien viste at det var fire områder i hjernen som var skadet. Et av områdene er hippocampus. Dette området har med korttidsminne og hukommelse å gjøre. (...)
Memory aging and brain maintenance
Trends in Cognitive Sciences 2012;16(5):292–305 (May 5)
Episodic memory and working memory decline with advancing age. Nevertheless, large-scale population-based studies document well-preserved memory functioning in some older individuals. The influential ‘reserve’ notion holds that individual differences in brain characteristics or in the manner people process tasks allow some individuals to cope better than others with brain pathology and hence show preserved memory performance. Here, we discuss a complementary concept, that of brain maintenance (or relative lack of brain pathology), and argue that it constitutes the primary determinant of successful memory aging. We discuss evidence for brain maintenance at different levels: cellular, neurochemical, gray- and white-matter integrity, and systems-level activation patterns. Various genetic and lifestyle factors support brain maintenance in aging and interventions may be designed to promote maintenance of brain structure and function in late life. (...)
Excessive Sleepiness May Be Cause of Learning, Attention and School Problems
sciencedaily.com 1.5.2012
ScienceDaily (May 1, 2012) — Children who have learning, attention and behavior problems may be suffering from excessive daytime sleepiness, even though clinical tests show them sleeping long enough at night, a new study reports.
Penn State researchers studied 508 children and found that those whose parents reported excessive daytime sleepiness (EDS) -- despite little indication of short sleep from traditional measurements -- were more likely to experience learning, attention/hyperactivity and conduct problems than children without EDS.
The culprits? Obesity, symptoms of inattention, depression and anxiety, asthma and parent-reported trouble falling asleep have been found to contribute to EDS even among children with no signs of diminished sleep time or sleep apnea.
"Impairment due to EDS in cognitive and behavioral functioning can have a serious impact on a child's development," said Susan Calhoun, PhD, the study's lead author. "When children are referred for neurobehavioral problems, they should be assessed for potential risk factors for EDS. Recognizing and treating EDS can offer new strategies to address some of the most common neurobehavioral challenges in young school-age children." (...)
SEQUELAE OF EXCESSIVE DAYTIME SLEEPINESS IN YOUNG CHILDREN
Learning, Attention/Hyperactivity, and Conduct Problems as Sequelae of Excessive Daytime Sleepiness in a General Population Study of Young Children
Sleep 2012;35(05)
(...) Conclusions: This study suggests that in a large general population sample of young children, parent-reported EDS is associated with neurobehavioral (learning, attention/hyperactivity, conduct) problems and poorer performance in processing speed and working memory. Impairment due to EDS in daytime cognitive and behavioral functioning can have a significant impact on children's development. (...)
Psilocybin Quiets Brain's Control Centers
scientificamerican.com 1.5.2012
Psychedelic drugs may work by dialing down brain activity in control centers (...)
Researchers have long suspected that the altered perception, kaleidoscopic visions and mood changes produced by psych¬edelic drugs reflect a jump in brain activity. Not so, say neuroscientists at Imperial College London and elsewhere. They used functional MRI to peek at the brains of 30 participants experiencing a “trip” induced by intravenously delivered psilocybin, a psychedelic found in magic mushrooms. As they reported in the Proceedings of the National Academy of Sciences USA online in January, investigators saw psilocybin-related dips in brain activity, particularly in control centers such as the thalamus, the anterior and posterior cingulate cortices, and the medial prefrontal cortex. The more placid these regions appeared in a participant’s brain, the more intense the subject’s self-reported psychedelic experiences. The scientists conclude that psychedelics temporarily flip off cognition-constraining pathways—including some that are overactive during depression. [For more on this study, click here.] (...)
- Vanlig sprøytemiddel "forstyrrer" barns hjerrner
Common Pesticide “Disturbs” the Brains of Children (Vanlig sprøytemiddel "forstyrrer" barns hjerrner)
blogs.scientificamerican.com 1.5.2012
Banned for indoor use since 2001, the effects of the common insecticide known as chlorpyrifos can still be found in the brains of young children now approaching puberty. A new study used magnetic imaging to reveal that those children exposed to chlorpyrifos in the womb had persistent changes in their brains throughout childhood.
The brains of 20 children exposed to higher levels of chlorpyrifos in their mother’s blood (as measured by serum from the umbilical cord) “looked different” compared to those exposed to lower levels of the chemical, says epidemiologist Virginia Rauh of the Mailman School of Public Health at Columbia University, who led the research published online by Proceedings of the National Academy of Sciences on April 30. “During brain development some type of disturbance took place.” (...)
(Anm: Miljø og helse (mintankesmie.no).) Intelligens er viktigere for karrièren enn nettverk
aftenposten.no 21.4.2012
Intelligens betyr mer for dine muligheter til å gjøre karrière enn bakgrunn og nettverk. Det viser en fersk studie fra universitetet i Tel Aviv. Resultatene får full støtte fra norsk nestor i arbeidspsykologi.
Ingen tvil om at bra familie og det å kjenne de rette folkene kan gi deg flere fortrinn og et godt utgangspunkt når du skal inn i arbeidslivet.
Men skal du virkelig oppnå fremgang, så er det intelligens, evner og personlighet som avgjør, ifølge arbeidspsykolog Espen Skorstad.
Debatten om hva som betyr mest for å oppnå suksess i arbeidslivet; hvem du kjenner eller hva du har mellom ørene, er ikke ny. Men mye på at de som holder på intelligens som den viktigste faktoren vinner terreng.
Nylig kom resultatene fra en stor, amerikansk studie, ledet av professor Yoav ved Tel Aviv University (TAU), basert på 25 års fortløpende studier av et utvalg på hele 12.868 amerikanere. Og konklusjonen, gjengitt på nettstedet sciencedaily.com, er klar: (...)
Autisme - mer miljø enn gener!
Tidsskr Nor Legeforen 2012; 132:786 (17.4.2012)
I Tidsskriftet nr. 4/2012 skriver Ragnhild Ørstavik (1) om en ny tvillingstudie fra Stanford University, som viste at miljøet hadde en større betydning enn gener (2). Camilla Stoltenberg ved Nasjonalt Folkehelseinstitut er ifølge innlegget ikke enig med de amerikanske forskerne (1).
Jeg synes derimot at studien høres plausibel ut. Allerede foreliggende studier viser at autister har skyhøye kvikksølvverdier målt i håret, en nedsatt evne til å skylle ut tungmetaller, og ofte positiv effekt av en kvikksølvutledende behandling (3, 4). Adams og medarbeidere (5) og Vojdani og medarbeidere (6) har undersøkt kvikksølvbelastningen hos autistiske barn og postulerer at det store forbruket av antibiotika hos disse barna er medansvarlig for de kjente mage-tarmproblemene, slik som intoleranse for melkekasein og gluten og blokkeringen for kvikksølvutrenskningen. (...)
(Anm: Mercury and autism: accelerating evidence? Neuro Endocrinol Lett 2005; 26: 439 - 46.)
Researchers Map Brain Regions Linked to Intelligence
news.yahoo.com 13.4.2012
FRIDAY, April 13 (HealthDay News) -- The physical architecture of intelligence in the brain has been mapped by scientists who used brain injury patients to conduct their research.
The findings provide new insight about the specific brain structures involved in general intelligence and specific skills such as memory and the ability to understand words.
The study included 182 Vietnam War veterans who had highly localized brain damage caused by penetrating head wounds.
"It's a significant challenge to find patients [for research] who have brain damage, and even further, it's very hard to find patients who have focal brain damage," study leader Aron Barbey, a professor of neuroscience at the University of Illinois, said in a university news release.
Many people who've suffered brain damage from stroke or other causes have multiple impaired brain areas. This makes it difficult to identify the specific functions of individual brain structures.
Studying people with highly localized brain damage enables researchers "to draw inferences about how specific brain structures are necessary for performance," Barbey said.
"By studying how damage to particular brain regions produces specific forms of cognitive [thinking] impairment, we can map the architecture of the mind, identifying brain structures that are critically important for specific intellectual abilities," he explained.
The participants in this study underwent CT scans and a number of tests of their intellectual abilities. The researchers found that "several brain regions, and the connections between them, were most important for general intelligence." (...)
The study was released online in advance of publication in an upcoming print issue of Brain: A Journal of Neurology. (...)
Harvard Medical School's Whole Brain Atlas has more about the brain. (...)
Seeking the Roots of Autism and Antisocial Personality in the Brain
healthland.time.com 10.4.2012 (Time)
Experts have long noted that both autism and antisocial personality disorder are marked by problems with empathy, yet the differences between the two conditions couldn’t be starker.
Autistic people are anxious and misread social cues, but they typically care about not hurting others; they are also often incapable of manipulation. Those with antisocial personality disorder, however, are masters of bending people to their will and tend to have little fear. They actually enjoy causing people pain.
In recent research, scientists highlighted the brain differences associated with autistic and antisocial traits, finding clear distinctions that remain stable during children’s development. Researchers imaged 323 typically developing youth, starting at an average age of 11. They children were also rated by their parents on levels of autistic and antisocial traits: for example, autistic traits might include “has difficulty relating to peers” or “would rather be alone than with others,” and parents would be asked to designate how well these phrases fit their child. Antisocial traits included things like “lies easily and skillfully” and “acts without thinking of the consequences.” (...)
Mom's Obesity May Sway Child's Risk for Autism
medpagetoday.com 9.4.2012
Mothers who are obese or who have diabetes appear to be more likely to have children with neurodevelopmental disorders, including autism, researchers found.
Maternal obesity was associated with greater odds of the offspring receiving a diagnosis of an autism spectrum disorder (OR 1.67, 95% CI 1.10 to 2.56) or a developmental delay (OR 2.08, 95% CI 1.20 to 3.61) by age 5, according to Paula Krakowiak, MS, a PhD candidate at the MIND Institute at the University of California Davis, and colleagues.
A combination of maternal metabolic conditions was associated with a range of impairments in the children's development, the researchers reported ahead of the May issue of Pediatrics. (...)
Vetenskapligt test kan förutse framgångar på fotbollsplanen
ki.se 5.4.2012
[PRESSMEDDELANDE 2012-04-05] Genom att mäta så kallade exekutiva kognitiva funktioner - förmågor som handlar om att snabbt lösa uppkomna problem - kan det vara möjligt att förutse hur bra en elitfotbollsspelare kommer att bli i framtiden, visar en ny studie från Karolinska Institutet. För första gången tror sig forskarna ha den vetenskapliga nyckeln till det som tidigare lite mystiskt beskrivits som "speluppfattning" hos framgångsrika fotbollsspelare.
Det har länge varit känt att ren fysisk styrka och bollsinne inte räcker för att bli riktigt bra på att spela fotboll. Istället har det ofta talats om en tredje mycket viktig komponent som kallats för speluppfattning (game intelligence), det vill säga en förmåga att kunna "läsa" spelet, alltid befinna sig på rätt plats vid rätt tidpunkt och vara en "måltjuv". Denna speluppfattning har för många varit något nästan magiskt som inte går att mäta.
Men enligt forskarna på Karolinska Institutet är speluppfattning knappast något mystiskt och obegripligt. Istället är det ett exempel på det man inom kognitionsvetenskapen kallar exekutiva funktioner, nämligen förmågan att vara kreativ i stunden och hela tiden se nya lösningar på problem, snabbt ändra taktik och revidera tidigare beteenden som inte fungerar.
- Våra hjärnor har specifika system som jobbar med information just på ett sådant sätt, och inom kognitionsvetenskapen finns det vedertagna metoder för att mäta hur välfungerande en persons exekutiva funktioner är, säger Predrag Petrovic vid institutionen för klinisk neurovetenskap.
I en studie, som nu presenteras i den vetenskapliga onlinetidskriften PLoS ONE, testade Predrag Petrovic och hans kollegor vissa exekutiva funktioner hos fotbollsspelare i allsvenskan respektive division 1, totalt cirka 57 elitspelare. Forskarna kunde då se att fotbollsspelare i båda grupperna var rejält mycket bättre i exekutiva test än normalbefolkningen. Men de kunde också se att spelarna i allsvenskan fick mycket bättre resultat i dessa test än spelarna i division 1. (...)
«80 prosent av bokserne viste tegn på hjerneskade en uke etter kamp»
aftenposten.no 4.4.2012
Cecilia Brækhus vil gjerne bokse proffkamper i Norge. Nå kan en ny, svensk undersøkelse være med å gjøre drømmen vanskeligere.
Svensk forskning kan få konsekvenser for norsk boksing.
Forskere og leger gir amatørboksingen en ny kilevink. En svensk undersøkelse viser at amatørboksere kan få varige hjerneskader.
Det er den medisinske komiteen i Det svenske bokseforbundet som har tatt initiativet til denne undersøkelsen, som avisen Göteborg-Posten også har vært med på, og konklusjonene skal være temmelig klare.
30 svenske amatørboksere var med i undersøkelsen. De hadde alle bokset minst 47 kamper. Alle bokserne ble undersøkt både en uke etter at de hadde vært i kamp, og deretter var de gjennom en ny undersøkelse etter en hvileperiode på to uker.
80 prosent av alle bokserne viste tegn på hjerneskade en uke etter at de hadde bokset kamp, og 20 prosent av de undersøkte bokserne viste tegn på dette etter at de hadde vært gjennom en hvileperiode, står det i rapporten etter undersøkelsen. (...)
Forskere: Katten din kan gjøre deg gal
vg.no 3.4.2012
FYTTI KATTA: Katteparasitten toxoplasma kan føre til alvorlige bivirkninger, visr forskning.
(VG Nett) For de aller fleste er bivirkningene helt udramatiske, men for noen kan det gå riktig galt.
Toxoplasma gondii er parasitten gravide frykter fordi den kan forårsake hjerneskade eller død hos fosteret. Nå viser forskning at parasitten også kan være skadelig for andre.
Parasitten Toxoplasma gondii sprer seg blant annet gjennom katteavføring. En av tre mennesker på verdensbasis kan være bærer av parasitten. Heldigvis er symptomene udramatiske for de fleste av oss.
Men den tsjekkiske professoren Jaroslav Flegr og flere av hans kolleger mener i fullt alvor at toxoplasma kan føre til 300000-400000 trafikkulykker i året på verdensbasis. Parasitten er også overrepresentert blant schizofrene.
Flegr har lenge forfektet disse teoriene, og har blitt tatt med større alvor de siste årene, skriver det amerikanske nyhetsmagasinet Atlantic.
Blant annet finnes det flere studier som viser en sammenheng med schizofreni og toxoplasma. (...)
Blodprov avslöjar autism
dn.se 29.3.2012
Forskare vid bland annat Linnéuniversitet i Kalmar har utvecklat ett test som, genom ett enkelt blodprov, avslöjar autism. På så sätt hoppas forskarna att det ska det bli möjligt att på ett tidigt stadium hitta och behandla barn med autism.
Bara några droppar blod kan räcka för att avslöja om ett barn har autism eller inte. (...)
Forskarna såg att ett specifikt protein processades, klipptes i bitar, olika hos barn med autism jämfört med hos friska barn.
– Två av bitarna är extremt förhöjda hos barnen med autism medan en annan bit fattas eller finns i väldigt låga halter, säger Bergquist, som är professor i analytisk kemi och neurokemi.
Forskarna hoppas att det snart ska bli möjligt att med hjälp av ett blodprov på ett tidigt stadium hitta och behandla barn med autism. (...)
Neuroscientists Can Stumble When They Make Conclusions from Examining Single Patients
blogs.scientificamerican.com 30.3.2012
Our current understanding of how the brain works often borrows from observations of the anomalous patient. The iron rod that penetrated Phineas Gage’s head made the once emotionally balanced railroad foreman impulsive and profane. But it gave neurologists clues as to the role of the brain’s frontal lobes in exercising self-control. The epilepsy surgery that removed Henry Molaison’s hippocampus opened a whole new line of research about memory.
Still, conclusions about mental processes from single patients arrive freighted with unavoidable risk. Neuroscientists can’t replicate what they find in neurologically damaged patients by removing a frontal lobe or hippocampus from other research subjects without planning for significant downtime in a state or federal prison.
That means that what we think we learn from an initial examination of a Gage or a Molaison may be less than meets the eye. The cautionary lessons of single-case neuroscience were underlined in a recent paper in Neuropsychologia by Marc Himmelbach and two colleagues at the Hertie-Institute for Clinical Brain Research, part of Eberhard Karls University in Tübingen, Germany. (...)
U.S. Autism Rate Rises to 1 in 88 Children, CDC Reports
news.yahoo.com 29.3.2012
THURSDAY, March 29 (HealthDay News) -- The rate of autism spectrum disorders continues to rise among American children, with one in 88 now receiving such a diagnosis, the U.S. Centers for Disease Control and Prevention reported Thursday.
That's an increase from the one in 110 estimate released by the CDC just two years ago. The newer data, from 2008, also shows that autism is almost five times more common in boys than girls, with one in 54 boys diagnosed with the condition.
Why the steady uptick in cases? That's not entirely clear, experts said.
"We know that people want answers to what's causing this increase, and so do we," Coleen Boyle, director of CDC's National Center on Birth Defects and Developmental Disabilities, said during a noon press briefing on Thursday.
"Some of the increase is due to the way children are identified, diagnosed and served," she said. "Although exactly how much is attributable to these factors is not known." (...)
Autism Rate Climbs Again (Autismeraten øker igjen)
medpagetoday.com 29.3.2012
In a large autism monitoring network, an estimated one out of every 88 8-year-olds had an autism spectrum disorder (ASD) in 2008, the most recent year with data available, CDC researchers reported.
That's a relative increase of 23% from a previous analysis of data from the same network for 2006, when the estimated prevalence was one out of 111 children, and a 73% relative increase from 2002, according to a surveillance summary in Morbidity and Mortality Weekly Report. (...)
Ser matteangst i hjernen
nrk.no 23.3.2012
- Den samme delen av hjernen som reagerer på skremmende situasjoner, som å se en edderkopp eller en slange, viser også en økt respons hos barn med mye matteangst, sier ekspert.
Tallskrekk er ikke innbilning. Forskere ser tydelige forskjeller i hjernene på barn med og uten matteangst.
Er mattestykker morsomme gåter som du gleder deg til å løse? Eller gir tallene deg vondt i magen og svette håndflater?
Hører du til siste kategori kan du ha matteangst – en spesiell form for skrekk som knytter seg nettopp til behandling av tall og ligninger, og som angivelig rammer nærmere 60 prosent av befolkningen.
Og nå mener altså amerikanske forskere at tallskrekken er en helt håndgripelig form for angst.
•Les: Abelprisen til ungarsk matematikar
Etter å ha fMRI-skannet 46 barn som løste addisjons- og subtraksjonsoppgaver, konkluderte teamet med at hjernen til de matteredde viste helt spesielle aktivitetsmønster.
- Den samme delen av hjernen som reagerer på skremmende situasjoner, som å se en edderkopp eller en slange, viser også en økt respons hos barn med mye matteangst, sier Vinod Menon i en pressemelding fra Stanford University. (...)
Da barna ble hjerneskannet, viste det seg derimot at hjernene til ulike barn reagerte forskjellig på matematikkoppgavene de ble satt til å løse.
De som hadde skåret høyt på matteangst, hadde høyere aktivitet i amygdala, hjernens hovedsenter for angst. Det samme gjaldt for en del av hippokampus som styrer med innlæring av nye minner. (...)
- Forskning har vist at matteangst har en negativ effekt på matematikkferdigheter, noe som har en uheldig innvirkning på karrierevalg, sysselsetting og profesjonell suksess, skriver forskerne i Psychological Science.
Det virkelig store spørsmålet er så klart hvordan denne skrullete skrekken har utviklet seg i utgangspunktet. Ble våre forfedre forfulgt av differensialligninger? (...)
Stenrig fond bevilger 121 millioner kroner til danske forskere, som skal finde årsagerne til psykisk sygdom
b.dk 19.3.2012
Over 100.000 mennesker med og uden psykisk sygdom skal have deres gener og anonymiserede livshistorie gransket i detaljer i et historisk stort psykiatrisk forskningsprojekt. Målet er at finde årsagen til psykisk sygdom.
- Vi håber, at ved at finde frem til årsagerne til psykisk sygdom, kan vi få en større indsigt i de biologiske mekanismer. Det kan hjælpe os med at udvikle bedre medicin og måske kan vi også tidligere udpege dem, der er i særlig risikogruppe, så vi kan tage bedre vare på dem, siger videnskabelig leder af projektet, professor i medicinsk genetik ved Aarhus Universitet, Anders Børglum.
Projektets officielle navn er "Lundbeckfondens Initiativ for Integreret Psykiatrisk Forskning", forkortet ”iPSYCH”. Den videnskabelige ledelse foregår fra Aarhus Universitet og Aarhus Universitetshospital, men i projektgruppen sidder også forskere fra Region Hovedstadens Psykiatri. Projektet skal se på fem sindslidelser: Skizofreni, maniodepressivitet, depression, autisme og ADHD.
- Det er alvorlige sindslidelser med stor udbredelse, og hvor behandlingstilbuddene i nogle tilfælde ikke er tilfredsstillende, så det ville vi gerne kunne gøre bedre. Men de senere år er vi også blevet klar over, at der er overlappende symptomer imellem de her sygdomme, og i høj grad også overlappende årsagsfaktorer, siger Anders Børglum. (...)
(Anm: Antidepressiva (SSRI) Lundbeck (mintankesmie.no).)
Medisin mot influensa vekker hjerneskadde
nrk.no 14.3.2012
Klinisk erfaring har lenge pekt på at legemidlet amantadin kan akselerere oppvåkningsfase for pasienter med hjerneskade. Men det er første gang forskerne har vitenskapelig bevis for hypotesen.
Et legemiddel mot influensa forkorter oppvåkningsfasen for pasienter med svært alvorlig hjerneskade. Det viser en internasjonal studie.
Hvert år legges 9.000 mennesker inn på norske sykehus med hodeskade, for eksempel etter et fall eller en trafikkulykke. En andel av disse, mellom 500 og 800 pasienter, har store skader.
Noen er så alvorlig skadet at de ikke våkner helt opp i løpet av de nærmeste månedene. Oppvåkningstiden har betydning for pasientens sjanser for å bli friske.
Men nå kommer gode nyheter for pasientene og deres pårørende. En internasjonal studie viser at legemidlet amantadin, som er et kjent middel mot influensa, kan påskynde oppvåkningsprosessen.
Studien er utført av blant andre danske forskere og nettopp publisert i tidsskriftet New England Journal of Medicine (NEJM).
Resultatet av studien peker mot at man på sikt kan hjelpe denne gruppen pasienter, mener overlege Annette Mosbæk Nordenbo. (...)
Avslører hjernesvikt
uib.no 13.3.2012
Personer med lavt nivå av signalstoffet glutamat har kraftigere blodgjennomstrømning i hjernen. Dette kan forklare kognitiv svikt hos schizofrene.
Sammen med sitt forskerteam har Kenneth Hugdahl, leder av fMRI-gruppen funnet svaret på et av de store uavklarte spørsmålene innenfor fMRI-forskning, nemlig at signalstoffet glutamat påvirker forandring i blodgjennomstrømning når mennesker løser en kognitiv oppgave.
– Jeg vil kalle det et gjennombrudd på grunnforskningsnivå. Det kan gi opphav til nye studier, undersøkelser og kliniske anvendelser om man benytter funnene i alt fra nevrologi til psykiatri, sier Hugdahl.
Drivstoff
Hjernen består av rundt 100 milliarder hjerneceller. Når man for eksempel hører og gjenkjenner en lyd kommuniserer nervecellene via elektrokjemiske impulser.
Med en MR-maskin kan forskerne måle blodgjennomstrømning til ulike områder i hjernen når forsøkspersonene får kognitive eller mentale oppgaver. Disse oppgavene kan gå ut på at forsøkspersonen skal lytte til språklyder, prøve å huske informasjon eller avgjøre ting på bakgrunn av instrukser. Når det skjer følger forskerne med på hvilke deler av hjernen som det plutselig går mer blod til.
I en av disse undersøkelsene ble også nivået av signalstoffet glutamat målt, med en metode som heter MR spektroskopi. Det var denne kombinasjonen som ga Bergensforskerne overraskelser. (...)
Duft af rosmarin kan booste din hjerne
videnskab.dk 13.3.2012
En æterisk olie i rosmarin kan forbedre hastigheden og præcisionen, når vi tænker. Det viser ny opsigtsvækkende forskning.
Rosmarin er siden oldtiden blevet hyldet for sine medicinske egenskaber.
Nu har hjerne-forskere fra Performance and Nutrition Research Centre på Northumbria University i England rent faktisk vist, at vores hjernes præstationsevne bliver forbedret, når vi har en rosmarinolie-komponent i vores blod.
Der er tale om stoffet 1,8-cineol, som bliver optaget i vores krop via næsen eller lungerne – altså, når vi indånder de æteriske olier, som rosmarin udsender.
»Hvis det er rigtigt, er det jo ret spændende. Folk i den alternative branche, der arbejder med aromaterapi, har længe hævdet, at de æteriske olier påvirker folks sindstilstand. Så for dem kommer det nok ikke som en overraskelse – og de vil nok sætte pris på videnskabelig evidens for, at æteriske olier virker.«
»Perspektivet her lyder jo som en naturlig performance-enhancer,« siger lektor Anna Jäger, der forsker i naturlægemidler ved Institut for Medicinalkemi, Københavns Universitet. (...)
Du husker mer jo raskere du leser
nrk.no 12.3.2012
Leser du fort, vil du ofte huske mer enn om du leser sakte.
Det kan ha sammenheng med at når du leser sakte, får du tid til å tenke på hva du skal ha til middag og hva som går på tv.
•TA TESTEN: Hvor flink er du til å huske navn?
Tren på å lese raskere
– Leser du raskt må du konsentrere deg om hva som står der. Du kan selv teste dette ved å legge inn en elektronisk tekst på lynlesing.no, og stille den inn på for eksempel 370 ord i minuttet, sier Hukommelseseksperten Oddbjørn By til NRK.no.
Normalt leser du 200 ord i minuttet, men ved hjelp av spesielle teknikker kan du komme opp i 800 eller 900 ord i minuttet.
– Men det er bare begynnelsem, det går an å fotografere sidene. Du kan lese opptil 25.000 ord i minuttet med den rette treningen, sier mentalisten Kurt Bai til NRK.no. (...)
Visualiser deg frem til navnet
nrk.no 12.3.2012
Vi skal ikke klandre oss selv hvis vi ikke klarer å huske navnet på ti personer i full fart. Pass på at du virkelig får med deg navnet, og bruk gjerne en teknikk.
Å huske navn er en treningssak. Her er noen triks for å bli flinkere til å huske navnene til de du møter.
Vi mennesker er flinke til å huske hvor vi møtte folk første gangen.
Hvis du tenker på nye folk du har hilst på de siste dagene, husker du sikkert hvor du møtte dem. Dette er en egenskap vi kan dra nytte av for å huske navn, skriver Oddbjørn By i boken «Best of Memo». (...)
QUIZ: Hvor flink er du til å huske navn?
nrk.no 12.3.2012 (...)
Slik husker du tall bedre
nrk.no 12.3.2012
Det er mulig å huske flere tall, mener Oddbjørn By. Han er norgesmester i hukommelse.
Alle kan bli en tallekspert. Gjør tallene til bilder, foreslår mannen som kan memorere en kortstokk på 43 sekunder. (...)
Cellgift påverkar hjärnan år efter behandling
lakemedelsvarlden.se 29.2.2012
Kvinnor som behandlas med cellgifter för bröstcancer tycks få något försämrat minne av behandlingen. De kognitiva försämringarna fanns kvar 20 år efter behandlingen, enligt en ny holländsk studie.
MINNET Tidigare studier har funnit att kvinnor som får kemoterapi får vad man kallat ”cellgiftshjärna” under och efter behandlingen, den nya rapporten är den första som testat bröstcancerpatienter långt efter att behandlingen avslutats. Forskarna understryker att man av studien inte självklart kan dra slutsatsen att det är just behandlingen med cellgifter som orsakar den kognitiva försämringen. Men ett par av forskarnas hypoteser är att cytostatika passerar från blodet in i hjärnan och dödar celler, eller att läkemedlens effekt på immunsystemet kan kopplas till den kognitiva förmågan.
Skillnaderna mellan kvinnor som fått cellgiftsbehandling och kvinnor som inte behandlats var dock små, påpekar forskarna. Av de 17 test som de tidigare 196 bröstcancerpatienterna fick göra 20 år efter behandlingen hade de något lägre poäng på sju av dem jämfört med de 1500 kvinnor som inte behandlats med cellgifter.
Även om skillnaderna som sagt var små, menar forskarna att även små skillnader kan få betydelse i ett längre perspektiv, till exempel att de cellgiftsbehandlade kvinnorna kan ha högre risk att få allvarliga försämringar.
Kvinnorna hade behandlats med cyklofosmaid, metotrexat och fluorouracil som inte längre används som kombinationsbehandling, men en del av dem används fortfarande. Forskarna menar att man troligen kan se samma effekt på den kognitiva förmågan även av modernare cytostatika.
De små kognitiva skillnaderna är dock inte något skäl att avstå från behandlingen, men det kan vara en hjälp för patienterna att känna till denna biverkan, menar forskargruppen. (...)
Poor Cognitive Function and Risk of Severe Hypoglycemia in Type 2 Diabetes
Post hoc epidemiologic analysis of the ACCORD trial
Diabetes Care 2012 (Published online before print February 28, 2012)
(...) OBJECTIVE Self-management of type 2 diabetes including avoidance of hypoglycemia is complex, but the impact of cognition on safe self-management is not well understood. This study aimed to assess the effect of baseline cognitive function and cognitive decline on subsequent risk of severe hypoglycemia and to assess the effect of different glycemic strategies on these relationships. (...)
CONCLUSIONS Poor cognitive function increases the risk of severe hypoglycemia in patients with type 2 diabetes. Clinicians should consider cognitive function in assessing and guiding their patients regarding safe diabetes self-management regardless of their glycemic targets. (...)
WELL; The Consumer: A Cocktail Of Drugs May Cloud The Brain
query.nytimes.com 28.2.2012
Many people are unaware that dozens of painkillers, antihistamines and psychiatric medications - from drugstore staples to popular antidepressants - can adversely affect brain function, mostly in the elderly. Regular use of multiple medications that have this effect has been linked to cognitive impairment and memory loss.
Called anticholinergics, the drugs block the action of the neurotransmitter acetylcholine, sometimes as a direct action, but often as a side effect. Acetylcholine is a chemical messenger with a range of functions in the body, memory production and cognitive function among them.
The difficulty for patients is that the effect of anticholinergic drugs is cumulative. Doctors are not always aware of all of the medications their patients take, and they do not always think to review the anticholinergic properties of the ones they prescribe. It's a particular problem for older patients, who are more vulnerable to the effects of these drugs and who tend to take more medicines over all.
Now a spate of new research studies has focused on anticholinergic medicines.
After following more than 13,000 British men and women 65 or older for two years, researchers found that those taking more than one anticholinergic drug scored lower on tests of cognitive function than those who were not using any such drugs, and that the death rate for the heavy users during the course of the study was 68 percent higher.
That finding, reported last July in The Journal of the American Geriatrics Society, stunned the investigators. (...)
(Anm: Anticholinergic syndrome (scribd.com).)
Autisme - arv eller miljø?
R Ørstavik
Tidsskr Nor Legeforen 2012; 132:408 (22.2.2012)
Ny tvillingstudie setter spørsmålstegn ved gamle sannheter om autisme.
Synet på årsakene til autisme endret seg dramatisk etter 1977, da en studie av tvillinger viste at eneggede mye oftere enn toeggede var konkordante for tilstanden. Autisme var altså ikke en konsekvens av at «kjøleskapsmødre» hadde avvist babyen, men derimot i høy grad genetisk betinget. I dag regner man med at autisme og autismespekterforstyrrelser har en arvbarhet på omkring 90 %. I en ny studie trekker imidlertid forfatterne oppmerksomheten tilbake til miljøfaktorene (1).
I undersøkelsen, som omfattet 192 tvillingpar fra California der minst én i paret hadde autisme eller autismespekterforstyrrelser, beregnet man en arvbarhet på under 40 %. Bidraget fra miljøfaktorer delt av tvillingene ble anslått til omkring 50 %. I en kommentarartikkel i samme nummer hevdes det at denne undersøkelsen er like betydningsfull som den fra 1977. (...)
Det er åpenbart at gener har stor betydning for autisme, selv om man kan diskutere hvor stor arvbarheten er. I tillegg kan det tenkes at miljøfaktorer fører til de novo-mutasjoner. Dette er mutasjoner som ikke arves fra foreldrene, men oppstår tidlig i fosterlivet. Flere slike mutasjoner som kan knyttes til autisme er oppdaget det siste året ved hjelp av gensekvensering.
- I ABC-studien, et underprosjekt av den norske mor- og barnundersøkelsen, studerer vi blant annet effekter av miljøpåvirkninger i fosterlivet. Hypotesen er at fostre med genetisk sårbarhet kan utvikle autisme dersom de utsettes for uheldige faktorer. Det kan dreie seg om infeksjoner, miljøgifter, medikamenter eller mangel på viktige næringsstoffer, sier Stoltenberg. (...)
Brain study finds what eases pain of financial loss
reuters.com 16.2.2012
(Reuters) - Financial market traders and keen gamblers take note. Scientists have found that a chemical in the region of the brain involved in sensory and reward systems is crucial to whether people simply brush off the pain of financial losses.
Scientists say the study points the way to the possible development of drugs to treat problem gamblers and sheds light on what may have been going on in the brains of Wall Street and City of London traders as the 2008 financial crisis took hold.
"Pathological gambling that happens at regular casinos is bad enough, but I think it's also happening a lot now at Casino Wall Street and Casino City of London," said Julio Licinio, editor of the Molecular Psychiatry journal which reviewed and published the brain study on Tuesday. (...)
"LOSS AVERSION"
The experiment showed that a neurotransmitter, or chemical messenger, called norepinephrine, or noradrenaline, is central to the response to losing money.
Those with low levels of norepinephrine transporters had higher levels of the chemical in a crucial part of their brain - leading them to be less aroused by and less sensitive to the pain of losing money, the researchers found.
People with higher levels of transporters and therefore lower levels of norepinephrine or noradrenaline have what is known as "loss aversion," where they have a more pronounced emotional response to losses compared to gains.
Loss aversion can vary widely between people, the researchers explained. While most people would only enter a two outcome gamble if it were possible to win more than they could lose, people with impaired decision making show reduced sensitivity to financial loss. (...)
Carlsen blir hyllet som «sjakkens Mozart» i USA
dagbladet.no 20.2.2012
VISES FRAM FOR MILLIONER: 60 Minutes er anerkjent over hele verden, og alt fra idrettsfolk til filmstjerner og politikere har blitt portrettert på samme måte som Magnus Carlsen ble i gårsdagens utgave. Video: CBS
Ble spurt om Bobby Fischers galskap på «60 Minutes».
(Dagbladet): I går kveld så potensielt rundt 15 millioner amerikanere 60 Minutes-innslaget med Magnus Carlsen, der journalist Bob Simon portretterer det norske sjakkgeniet som han tidligere har gjort det med stjernenavn som Angelina Jolie og Manny Paquiao - for å nevne to helt vilkårlige.
Manager Espen Agdestein fikk gåsehud av resultatet på CBS.
- Ja, det var veldig gøy å se, sier han til Dagbladet. (...)
Autism Signs Appear in Brains of 6-Month-Old Infants
scientificamerican.com 18.2.2012
The findings suggest that there is a potential to disrupt autism during a child's first year before the disorder becomes entrenched (...)
Bør man fjerne burhøns' hjerner?
b.dk 18.2.2012
Et nyudviklet projekt, hvor burhøns har fået fjernet deres hjerner og dyrkes i Matrix-lignende kapsler, vækker debat.
Ville du have det bedre med at spise æg og kød fra burhøns, hvis man nu havde sørget for at fjerne deres hjerner, så de ikke opdager, hvor skidt de har det?
Den tanke har arkitektstuderende André Ford fra Royal College of Art i London undersøgt til bunds ved at designe et system til masseproduktion af kyllinger, hvor fuglenes hjernebark er fjernet, så de ikke længere oplever lidelsen ved at være mast tæt sammen. Eller oplever noget som helst, for den sags skyld.
Kyllingernes hjernestamme er bevaret, så kroppens øvrige funktioner fungerer normalt. De hjernedøde fuglekroppe er herefter spændt op i opretstående, pladsbesparende rammer, som minder om de netværk af kapsler fyldt med menneskekroppe, man ser i scifi-filmen ”The Matrix”. (...)
Motor Impairments Appear to Be a Characteristic of Autism
news.yahoo.com 17.2.2012
FRIDAY, Feb. 17 (HealthDay News) -- Autism itself seems to be responsible for the problems children with the disorder have in developing motor skills such as running, throwing a ball and learning to write, according to a new study.
Previously, it wasn't clear whether these motor skill difficulties ran in families or were linked to autism, said the researchers at the Washington University School of Medicine in St. Louis.
The investigators studied children from 67 families that had at least one child with autism spectrum disorder and a sibling in the same age group. Twenty-nine families had two children with autism, including six identical twins, and 48 families had only one child with the disorder. (...)
Brain Injury Rate 7 Times Greater among U.S. Prisoners (Hyppighet av hjerneskader 7 ganger høyere blant innsatte amerikanere)
scientificamerican.com 4.2.2012
Prisoners suffer disproportionately from past traumatic brain injuries. Researchers are hunting for the best tools to treat this population in an effort to help them reintegrate into society--and avoid re-incarceration
The Science of Concussion and Brain Injury How medicine, sports and society are trying to heal and protect the brains of millions amidst the growing awareness of the long-lasting effects of traumatic head injury »February 3, 2012.
Hitting prisoners hard: Traumatic brain injuries, including previous concussions, affect a disproportionate segment of incarcerated adults--and might be to blame for behavioral issues and many cases of re-arrest.
A car accident, a rough tackle, an unexpected tumble. The number of ways to bang up the brain are almost as numerous as the people who sustain these injuries. And only recently has it become clear just how damaging a seemingly minor knock can be. Traumatic brain injury (TBI) is no longer just a condition acknowledged in military personnel or football players and other professional athletes. Each year some 1.7 million civilians will suffer an injury that disrupts the function of their brains, qualifying it as a TBI.
About 8.5 percent of U.S. non-incarcerated adults have a history of TBI, and about 2 percent of the greater population is currently suffering from some sort of disability because of their injury.
In prisons, however, approximately 60 percent of adults have had at least one TBI—and even higher prevalence has been reported in some systems. These injuries, which can alter behavior, emotion and impulse control, can keep prisoners behind bars longer and increases the odds they will end up there again. Although the majority of people who suffer a TBI will not end up in the criminal justice system, each one who does costs states an average of $29,000 a year.
With more than two million people in the U.S. currently locked up—and millions more lingering in the justice system on probation or supervision—the widespread issue of TBI in prison populations is starting to gain wider attention.
(...)
The Science of Concussion and Brain Injury
scientificamerican.com 3.2.2012
How medicine, sports and society are trying to heal and protect the brains of millions amidst the growing awareness of the long-lasting effects of traumatic head injury (...)
Inside Story: What Happens When Brain Hits Skull
scientificamerican.com 2.2.2012
Watch the frightening mechanics of a concussive blow to the head
The Science of Concussion and Brain Injury How medicine, sports and society are trying to heal and protect the brains of millions amidst the growing awareness of the long-lasting effects of traumatic head injury »February 3, 2012.
Concussion, the most common among traumatic brain injuries, which occurs 1.7 million times a year in the U.S., represents a major public-health problem. It occurs when there is a sudden acceleration or deceleration of the head, a process depicted here in this animation.
A blow can produce a brief loss of consciousness, headaches and impaired cognition, among other symptoms. Symptoms can last for days or sometimes longer. And a person who experience one risks another and may find recovery takes longer.
Scientists continue to learn more about the nefarious consequences of repeated concussions. In the February issue of Scientific American, writer Jeffrey Bartholet details in “The Collision Syndrome evidence for yet another neurodegenerative disorder that can result from concussions. (...)
Hjernar kan vere programmert for å bli rusavhengige
nrk.no 4.2.2012
Hjerneskanningar av syskenpar der den eine misbruker narkotika og den andre ikkje.
Hjerneskanningar viser at sysken av rusmisbrukarar deler misdanningar i det same område av hjernen. Dette kastar lys på kvifor risiko for å bli avhengig går i familien.
Forskarar ved University of Cambridge skanna hjernane til femti syskenpar, der det eine syskenet er avhengig av kokain eller crack, mens den andre ikkje misbruker verken narkotika eller alkohol.
Hjernane deira vart også samanlikna med hjernane til femti friske frivillige.
Dei fann avvik i hjernane til begge syskena, i eit område av hjernen som har med sjølvkontroll å gjere.
Studien som er publisert i Science tyder altså på at enkelte av oss arvar ein hjerne som gjer oss meir tilbøyelege til å bli avhengige av eit rusmiddel. (...)
Overvægt kan gå ud over din hjerne
fpn.dk 3.2.2012
Ældre personer med livslang overvægt har en reduceret hjernestørrelse, viser ny forskning.
Den del af hjernen, der blandt andet styrer appetitten, er kraftigt reduceret hos ældre personer, der samtidig lider af overvægt.
Det viser ny forskning foretaget på universitetet i Uppsala i Sverige. Dårlige spisevaner over en længere periode knyttes derfor nu sammen med muligheden for, at hjernen bliver svagere.
Ved hjælp af MR-scanning undersøgte forskere hjernen på 292 personer, som igennem en periode på fem år enten var konstant normalvægtige eller overvægtige. Hos den overvægtige gruppe fandt man en reduktion på størrelsen af den forreste del af hjernen i forhold til de normalvægtige.
Forskerne gik herefter igang med at undersøge, om de kunne finde en sammenhæng mellem en persons overvægt og den hjernefunktion, der styrer appetitten. Resultatet viste kognitive mangler hos de overvægtige personer. (...)
Study Finds Link Between Heart Failure, Brain Changes (Studie finner link mellom hjertesvikt og hjerneforandringer)
health.yahoo.com 1.2.2012
WEDNESDAY, Feb. 1 (HealthDay News) -- Heart failure is associated with a loss of gray matter in the brain and a decline in mental processes, according to a new study.
These changes can make it more difficult for heart failure patients to remember and perform health care instructions such as taking the correct medications at the right times, the Australian researchers said.
They conducted memory and other mental performance tests on 35 heart failure patients, 56 patients with ischemic heart disease (which sometimes but not always accompanies heart failure), and 64 healthy people. MRI exams were used to assess gray matter volume in different parts of the brain.
In heart failure, the heart muscle is unable to pump enough oxygen-rich blood to the body, while ischemic heart disease affects the supply of blood to the heart.
Heart failure patients had worse immediate and long-term memory and reaction speeds than healthy people. The brain scans showed that heart failure was associated with losses of gray matter in areas believed to be important for memory, reasoning and planning.
The study appears online Feb. 1 in the European Heart Journal. (...)
Antibody-mediated encephalitis: a treatable cause of schizophrenia
Editorial
The British Journal of Psychiatry (2012) 200: 92-94 (February)
Psychiatrists need to be vigilant for the newly recognised and treatable disorder of antibody-mediated encephalitis. Psychiatric symptoms are common, and individuals with the disorder often present initially to psychiatric services. We describe the clinical features of the disorder and make recommendations for further investigations. (...)
Certain Brain Cells Become Toxic in Lou Gehrig's Disease
scientificamerican.com 25.1.2012
Brain cells known for assisting neurons may be killing them in patients with ALS
Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease, is a progressive neuromuscular disease that affects about 130,000 people worldwide a year. The vast majority of patients are isolated cases with no known family history of the disease. They usually start developing symptoms of the loss of motor neurons in middle age and die within five years of diagnosis. Researchers know very little about what causes ALS. Now a recent study in Nature Biotechnology suggests that the neuron death associated with the disease may be caused by astrocytes, a type of brain cell that normally helps neurons.
Previous research had suggested that astrocytes could become toxic in the rare form of ALS known to have genetic roots, and the study authors wanted to see if a similar phenomenon might happen in the more common isolated cases. The answer turned out to be yes: when they cultured astrocytes from those ALS patients, the healthy motor neurons in the culture began to die off after a few days. Other types of neurons were unaffected by the astrocytes, suggesting that they specifically harm the neurons involved in controlling the body’s movements. (...)
Severe Brain Injury When Young May Have Long-Term Effects
consumer.healthday.com 23.1.2012
Good home environment helps overcome some deficits, studies find
MONDAY, Jan. 23 (HealthDay News) -- Although many people believe young children are extremely resilient after they are seriously hurt, the opposite may be true with traumatic brain injuries.
Two Australian studies looked at the impact of traumatic brain injury in children as young as 2 years, and found that these injuries affected cognitive function, IQ and even behavior for some time. However, the researchers also found that recovery from traumatic brain injury can continue for years after the initial injury. And, a child's home environment can positively influence recovery if the child lives in a stable, caring home. (...)
Autistiske børn havde særlige bakterier i kroppen
videnskab.dk 15.1.2012
Autistiske børns tarmflora ser ud til at indeholde bakterier, som ikke findes hos andre unge. Det styrker mistanken om, at tarmproblemer kan hænge sammen med autisme.
Det er en kendt sag, at mange børn med autisme også kæmper med problemer med fordøjelsessystemet. Der findes til og med også forskning, som peger mod, at graden af maveproblemer bliver forhøjet i takt med styrken af de autistiske træk.
Kan de to tilstande hænge sammen på en eller anden måde?
Tidligere forskning har vist forskelle i afføringsprøver fra børn med og uden autisme.
Og nu er forskere ved Columbia University gået et skridt videre. Teamet har taget prøver fra blindtarmen og den nederste del af tyndtarmen på 23 børn med både autisme og tarmproblemer, og på 9 børn kun med fordøjelsesproblemer. (...)
Is There a Difference between the Brain of an Atheist and the Brain of a Religious Person?
scientificamerican.com 16.1.2012
Is there a difference between the brain of an atheist andthe brain of a religious person?
Andrew Newberg, director of research at the Myrna Brind Center of Integrative Medicine at Thomas Jefferson University and Hospital in Philadelphia, responds:
Researchers have pinpointed differences between the brains of believers and nonbelievers, but the neural picture is not yet complete.
Several studies have revealed that people who practice meditation or have prayed for many years exhibit increased activity and have more brain tissue in their frontal lobes, regions associated with attention and reward, as compared with people who do not meditate or pray. A more recent study revealed that people who have had “born again” experiences have a smaller hippocampus, a part of the brain involved in emotions and memory, than atheists do.
These findings, however, are difficult to interpret because they do not clarify whether having larger frontal lobes or a smaller hippocampus causes a person to become more religious or whether being pious triggers changes in these brain regions.
Various experiments have also tried to elucidate whether believing in God causes similar brain changes as believing in something else. The results, so far, show that thinking about God may activate the same parts of the brain as thinking about an airplane, a friend or a lamppost. For instance, one study showed that when religious people prayed to God, they used some of the same areas of the brain as when they talked to an average Joe. In other words, in the religious person’s brain, God is just as real as any object or person. (...)
Ny forskning: Viktige cellemotorer raver rundt
aftenposten.no 13.1.2012
Harvard-forskere forbløffet da mikroskopet viste kroppens "silly walker".
Komikergruppen Monty Python gledet verden med sine "silly walks". Videobasen Youtube er full av etterligninger og nye varianter.
Her kommer et bidrag til, fra Harvard Medical School. Der kan cellebiologen Samara Reck-Peterson og hennes kolleger nå avsløre at én av kroppens flittigste arbeidere ikke stamper stødig fremover slik man har trodd, men faktisk raver som om den var kraftig påseilet.
Og dette spesielle ganglaget er faktisk årsaken til at den lille krabaten klarer oppgavene sine så fantastisk godt, mener forskerne som har publisert sitt materiale i tidsskriftet Nature Structural & Molecular Biology. (...)
Oslo - Stavanger
Det du ser på videoen ovenfor, er et dynein. Det er en liten motor som frakter nyttelast langs cellenes intrikate nettverk av småveier og motorveier. Og motorveien kan være lang, spesielt i nerveceller - i vår skala kan oppgaven sammenlignes med det å skulle gå på sine bein fra Oslo til Stavanger.
- Dyneinet er som en bilmotor. Men i stedet for hjul er motoren utstyrt med bein, forklarer professor Oddmund Bakke ved Institutt for molekylær biovitenskap, Universitetet i Oslo. (...)
Forstå sykdommer
Både i Oslo og på Harvard forsøker biologene å forstå hvordan dynein-motorene fungerer.
Harvard-forskerne har festet fluoriserende materiale på motorens lange bein og lagt både motor og motorvei under mikroskopet.
Her er dyneinets ferd langs cellenes motorveier
Cellemotoren kan bevege seg fremover og bakover, og fra side til side.
- Om vi klarer å kartlegge og tolke mekanismene i dynein-motorer og andre ørsmå cellemaskiner, har vi håp om å kaste lys over det molekylære utgangspuntet for endel sykdommer, sier Reck-Peterson.
Den travle skytteltrafikken holder cellene i live, sørger for at celler flytter på seg og deler seg - og at de snakker med naboene sine. Om motorene streiker, blir det problemer. Svikt i den dynein-baserte transporten knyttes til alvorlige sykdommer som Parkinsons og Lou Gehrigs sykdom. (...)
Molecular Motor Struts Like Drunken Sailor
focushms.com 8.1.2012
Monty Python may claim credit for immortalizing the “silly walk,” but molecular biology beat the comedy troupe to the punch. It turns out that a tiny motor inside of us called dynein, one tasked with shuttling vital payloads throughout the cell’s intricate highway infrastructure, staggers like a drunken sailor, quite contrary to the regular, efficient poise of its fellow motors.
But researchers led by Samara Reck-Peterson, HMS assistant professor of cell biology, believe dynein’s theatrical strut and apparent inefficiency may help keep cells alive and healthy.
These findings appear online January 8 in Nature Structural & Molecular Biology.
Molecular motors, built from proteins, are a kind of transport service that keep cells functioning. They traffic essential chemical packages between the heart of the cell, the nucleus, and the cell periphery. In elongated cells such as neurons, this can be a big commute in cellular miles, equivalent to a person walking from Boston to Manhattan. The constant shuttling of materials by motors keeps cells alive, allows cells to move and divide, and talk to their neighbors.
It’s no surprise, then, that when these motors stop functioning, serious problems can result. In fact, defects in dynein-based transport have been linked to Lou Gehrig’s and Parkinson’s disease and the neurodevelopmental disease lissencephaly.
To understand how molecular motors work, some researchers are creating animations. Here, each “leg” of a molecular motor called dynein moves as it progresses along a cellular structure called a microtubule. New data suggest that dynein’s walk is even stranger than the one modeled. Animation by Janet Iwasa. (...)
The Neuroscience of Looking on the Bright Side (Nevrovitenskapens syn på de lyse sider)
scientificamerican.com 12.1.2012
Scientists use "prediction errors" to understand the brain's natural optimism
Ask a bride before walking down the aisle “How likely are you to get divorced?” and most will respond “Not a chance!” Tell her that the average divorce rate is close to 50 percent, and ask again. Would she change her mind? Unlikely. Even law students who have learned everything about the legal aspects of divorce, including its likelihood, state that their own chances of getting divorced are basically nil. How can we explain this?
Psychologists have documented human optimism for decades. They have learned that people generally overestimate their likelihood of experiencing positive events, such as winning the lottery, and underestimate their likelihood of experiencing negative events, such as being involved in an accident or suffering from cancer. Informing people about their statistical likelihood of experiencing negative events, such as divorce, is surprisingly ineffective at altering their optimistic predictions, and highlighting previously unknown risk factors for diseases fails to engender realistic perceptions of medical vulnerability. How can people maintain their rose-colored views of the future in the face of reality? Which neural processes are involved in people’s optimistic predictions?
To answer these questions we have investigated optimism by using a recent, burgeoning approach in neuroscience: Describing neural activity related to complex behavior with the simple concept of “prediction errors.” Prediction errors are the brain’s way of keeping track of how well it is doing at predicting what is going to happen in the future. (...)
Autistic Children Have Different Guts
Ivanhoe.com 13.1.2012
(Ivanhoe Newswire)-- An interesting observation has been made that many autistic children have a different kind of bacteria in their intestinal tract than non-autistic children do.
Brent Williams and colleagues at the Mailman School of Public Health at Columbia University found that bacteria belonging to the group Sutterella are one of the major populations of microorganisms living in the gut of some autistic children. Sutterella was not found in tissue samples from non-autistic children.
It is an enigma what the correlation is between the developmental disorder autism and the existence of Sutterella. Jorge Benach, Chairman of the Department of Microbiology at Stony Brook University and a reviewer of the report is quoted as saying, "Sutterella has been associated with gastrointestinal diseases below the diaphragm, and whether it's a pathogen or not is still not clear. It is not a very well-known bacterium." (...)
Why Remembering Names Is Hard — And What to Do About It
healthland.time.com 13.1.2012 (Time)
Can't remember people's names but can rattle off phone numbers without a hitch? There's a reason for that
I’m utterly horrible at remembering names, something that always seemed odd to me because my memory is otherwise quite decent. Give me a statistic or an odd fact and generally it will stick— but introduce me to someone and milliseconds later, the name is gone.
That’s why I was delighted to see this round-up of research on the issue on an excellent British psychology blog, PsyBlog. So why are names so tricky even for people with good memories to recall? (...)
- INTERNETT ER LIKE FARLIG FOR HJERNEN SOM KOKAIN
SIDE3.NO 12.1.2012
Internettavhengighet kan ifølge forskere skape den samme typen endringer i hjernen som personer som er avhengig av sterke narkotiske stofer.
Ny forskning avslører skremmende sammenheng.
Tro det eller ei, men det finnes en del mennesker som blir avhengig av internett. Fenomenet er formelt klassifisert som «Internett addiction disorder», selv om det er noe omdiskutert. Formelt er det klassifisert som en impulskontrollforstyrrelse.
Det handler i stor grad om overbruk og avhengighet av porno, online-spilling, sosiale medier, blogging og netthandling.
Det er dokumentert at personer som lider av dette kan oppleve abstinenssymptomer som skjelving, ukontrollerte bevegelser, depresjon og tvangstanker. (...)
Skaper hjerneendringer
Men nå har et kinesisk forskningsteam sett nærmere på hvordan internettavhengighet påvirker hjernen, ikke bare hvordan symptomene er. De sammenlignet derfor 17 personer med diagnosen internettavhengighet, med 16 personer som ikke hadde avhengigheten.
Ifølge Huffington Post fant forskerne klare forskjeller. Hos personene som var internettavhengige fant de forstyrrelser i den såkalte hvite substansen i hjernen, nervefibre som kobler sammen vitale deler av hjernen som kontrollerer ting som følelser, beslutningstaking og selvkontroll.
MR-resultatene viste at nervefibrene generelt var i dårlig stand.
- Våre funn tyder på at internettavhengige hadde en utbredt reduksjon av «fractional anisotropy» (FA) i de store hvite substansveiene og en slik unormal struktur kan settes i sammenheng med enkelte atferdsproblemer, sier Dr Hao Lei i Chinese Academy of Sciences i Wuhan.
Han legger til at dette betyr at behandling av nettavhengighet kan fokusere på dette feltet i større grad. (...)
Study: Cognitive Decline Sets in as Early as Age 45
healthland.time.com 6.1.2012 (Time)
Our brains become less sharp as we age, but when does the decline actually start? You might be surprised
A new study of British civil servants shows that cognitive skills such as memory and reasoning are already declining, typically, among people as young as 45.
Researchers from France and England looked at data from the Whitehall II cohort — a group of roughly 10,000 government employees in London who have been studied since the mid-1980s. Through the years, study participants have answered surveys and given information about all aspects of their lives, from diet to education, as well as agreed to undergo special medical exams.
The results of all that testing are published this week in the journal BMJ (formerly called the British Medical Journal). They show that, on average, performance on the cognition tasks worsened as the subjects got older. The declines were steepest among the oldest participants, who were aged 65-70 at the beginning of the 10-year study period in 1997-99. But even for the youngest participants, aged 45-49 in 1997-99, average skills declined with age in every one of the test categories except vocabulary. (...)
Timing of onset of cognitive decline: results from Whitehall II prospective cohort study
BMJ 2012;344:d7622 (5 January)
Objectives To estimate 10 year decline in cognitive function from longitudinal data in a middle aged cohort and to examine whether age cohorts can be compared with cross sectional data to infer the effect of age on cognitive decline. (...)
Main outcome measure Tests of memory, reasoning, vocabulary, and phonemic and semantic fluency, assessed three times over 10 years.
Results All cognitive scores, except vocabulary, declined in all five age categories (age 45-49, 50-54, 55-59, 60-64, and 65-70 at baseline), with evidence of faster decline in older people. In men, the 10 year decline, shown as change/range of test×100, in reasoning was −3.6% (95% confidence interval −4.1% to −3.0%) in those aged 45-49 at baseline and −9.6% (−10.6% to −8.6%) in those aged 65-70. In women, the corresponding decline was −3.6% (−4.6% to −2.7%) and −7.4% (−9.1% to −5.7%). Comparisons of longitudinal and cross sectional effects of age suggest that the latter overestimate decline in women because of cohort differences in education. For example, in women aged 45-49 the longitudinal analysis showed reasoning to have declined by −3.6% (−4.5% to −2.8%) but the cross sectional effects suggested a decline of −11.4% (−14.0% to −8.9%).
Conclusions Cognitive decline is already evident in middle age (age 45-49). (...)
When Viruses Invade the Brain
scientificamerican.com 28.12.2011
Neurodegenerative diseases may result from a nasal infection (...)
Neuroscientist Steven Jacobson and his colleagues at the National Institute of Neurological Disorders and Stroke have determined that the virus makes its entry to the human brain through the olfactory pathway, right along with the odors wafting into our nose.
The researchers tested samples of brain cells from people with MS and healthy control subjects and found evidence of the virus in the olfactory bulb in both groups. Infection via the nasal passage is probably quite common, as is harboring a dormant reservoir of HHV-6, but in people with MS, the virus is active. Genetics and other unknown environmental factors probably determine the likelihood of the virus reactivating once inside the brain, which can cause the disease to progress.
The virus appears to invade the brain by infecting a type of glial cell called olfactory ensheathing cells (OECs), which nourish smell-sensing neurons and guide them from the olfactory bulb to their targets in the nervous system. These targets include the limbic system, a group of evolutionarily old structures deep in the brain, “which is where viruses like to reactivate,” Jacobson explains. He points out that olfactory neurons and their OECs are among the few brain cells known to regenerate throughout our life. This neurogenesis may keep our sense of smell sharp, but at the cost of providing the virus the opportunity to spread. (...)
Aging Brains Match Youth in Some Mental Tasks
scientificamerican.com 28.12.2011
Older people slow down to avoid making errors, but there may not be a uniform decline in all cognitive processes (...)
Memory in old age
Some memory tasks do decline with age, though. "If you look at aging research, you find some studies that show older people are not impaired in accuracy, but other studies that show that older people do suffer when it comes to speed," Ratcliff said.
Previous research has shown that a mental facility called "associative memory" — remembering two connected memories together — declines as people age. There's still hope for other types of brain tasks, though. Perhaps not all brainpower declines at the same rate in the aging brain, the researchers suggest.
"The older view was that all cognitive processes decline at the same rate as people age," Ratcliff said. "We're finding that there isn't such a uniform decline. There are some things that older people do nearly as well as young people."
The study was published in the January issue of the journal Child Development. (...)
Brain Injury Linked to Violent Acts
medpagetoday.com 28.12.2011
Individuals who've had a severe traumatic brain injury are at subsequent risk for violent behavior, but the same association was not seen for patients with epilepsy, Swedish researchers found.
Compared with the general population, adults with traumatic brain injury had an adjusted odds ratio for a later conviction for a violent offense of 3.3 (95% CI 3.1 to 3.5), which was a 5.8% absolute increase in risk, according to Seena Fazel, MD, of Oxford University in Oxford, England, and the Karolinska Institute in Stockholm, and colleagues.
Patients with epilepsy, in contrast, had an odds ratio for violence of 1.5 (95% CI 1.4 to 1.7) after adjusting for age, sex, and sociodemographic factors, but this increase was no longer present after adjusting for familial confounding (OR 1.1, 95% CI 0.9 to 1.2), the researchers reported online in PLoS Medicine. (...)
New Treatment for Brain Aneurysms
ivanhoe.com 21.12.2011
NASHVILLE, TN ( Ivanhoe Newswire) -- They’re often discovered when it’s too late and one in 15 people could develop them in their lifetime. Brain aneurysms are abnormal bulgings of arteries. When they rupture, stroke, brain damage or death can follow. Catching the problem in time usually means cutting open the skull to treat it. A new procedure is giving some patients a leg up! (...)
Akademisk doping
universitetsavisa.no 21.12.2011
1 av 5 akademikere verden over anvender legemidler for å forbedre sin intellektuelle prestasjonsevne. Hvis medikamenter gjør oss smartere, hva er galt i å bruke dem?
Såkalte smartdrugs er på vei inn i akademia, advarer amerikanske nevroforskere. Smartmedisiner kan øke den intellektuelle prestasjonsevnen. Dermed bør man vurdere å innføre dopingtester ved universitetene.
Det begynte med medisiner mot lidelser som Alzheimers, narkolepsi, ADHD, MBD og andre “bokstav-sykdommer”. Det dreier seg om medikamenter som påvirker den kognitive evnen. Etter hvert er disse, og liknende, medisiner blitt tatt i bruk også av personer uten noen form for diagnose. (...)
Streng diett kan holde hjernen frisk
vg.no 20.12.2011
Ved å spise mindre kan man holde hjernen frisk, ifølge italienske forskere.
Forskerne har gjennomført en undersøkelse hvor mus ble gitt kun 70 prosent av den næringen de vanligvis ville fått. Dietten førte til aktivering av CREB1, et proteinmolekyl som er viktig for hjernens funksjonsevne.
- Vårt håp er at vi nå kan finne en måte å aktivere CREB1 på, for eksempel gjennom legemidler, slik at hjernen kan holdes ung uten at man trenger å følge en streng diett, sier Giovambattista Pani, som ledet forskningsprosjektet.
Forskernes resultater er lagt fram i siste utgave av forskningstidsskriftet Proceedings of the National Academy of Sciences. (...)
When Lobotomy Was Seen as Advanced (Da lobotomi ble oppfattet som et fremskritt)
nytimes.com 19.12.2011
Most of us recall lobotomies as they were depicted in the movie “One Flew over the Cuckoo’s Nest”— horrifying operations inappropriately used to control mentally ill patients. But in the 1950s, surgeons also used them to treat severe pain from cancer and other diseases.
Now a Yale researcher has uncovered surprising new evidence of a famous patient who apparently received a lobotomy for cancer pain during that time: Eva Perón, the first lady of Argentina, who was known as Evita. The story is an interesting, sad footnote in the history not only of lobotomy, but of pain control.
The nature of Perón’s illness was initially shrouded in silence. Her doctors diagnosed advanced cervical cancer in August 1951, but as was common at the time, the patient was told only that she had a uterine problem. According to the biographers Nicholas Fraser and Marysa Navarro, secrecy was so paramount that an American specialist, Dr. George Pack, performed Perón’s cancer operation without her or the public ever knowing. He entered the operating suite after she was under anesthesia.
Despite surgery, radiation and chemotherapy, Perón gradually worsened, dying in late July 1952 at age 33. Only then was it revealed that she had died of cervical cancer, although details of her treatment, including Dr. Pack’s involvement, remained concealed.
In a 1972 biography, Erminda Duarte, Perón’s sister, claimed she had suffered intense pain and distress.
When used for psychiatric illness, lobotomy was once seen as a huge advance. Dr. Egas Moniz, a Portuguese neurologist who developed the procedure in the 1930s, was awarded the Nobel Prize in Physiology or Medicine in 1949. Surgeons performed many types of lobotomies, but most involved severing nerves that ran from the frontal lobes to other parts of the brain to disrupt supposedly faulty connections that had developed in schizophrenia or depression.
Lobotomies for mental illness fell out of favor in the 1960s because of the development of effective antipsychotic medications, misuse of the procedure and a growing unease among doctors with the confusion and stupor that resulted from the operation. (...)
Nevro ditt og nevro datt
morgenbladet.no 16.12.2011
Det er på tide at humanistene tar til motmæle mot overivrige psykologer og hjerneforskere, mener den britiske kritikeren Raymon Tallis.
Når aviser som Wall Street Journal og magasiner som Prospect eller The Times Literary Supplement trenger noen til å skrive noe kritisk om den siste populære boken om hjernevitenskap, kontakter de gjerne briten Raymon Tallis. Han er professor emeritus i medisin og kjent som litteraturkritiker, poet og distinguished member av den britiske humanistforeningen. Tallis har markert seg i den allmenne diskusjonen om nevrovitenskapens betydning for synet på mennesket, og er for tiden aktuell med boken Aping mankind. Neuromania, Darwinitis and the Misrepresentation of Humanity (Acumen Publishing).
– Oh dear, sier Tallis til Morgenbladet når vi forteller at Anders Behring Breivik nektet å gjennomføre en hjerneskanning. – Men heldigvis taper ingen noe på det. (...)
Childhood disorder bolsters research on infection link
seattletimes.nwsource.com 14.12.2011
Children have obsessive-compulsive disorder that occurs suddenly — and often dramatically — within days or weeks of a simple infection, such as strep throat. (...)
The bizarre illness, first recognized in the mid-1990s, has been cloaked in controversy. Now, however, studies are reinforcing the belief that some psychiatric illnesses can be triggered by ordinary infections and the body's immune response. The theory remains unproved, but the research raises the possibility that some cases of mental illness might be cured by treating the immune system dysfunction.
"Some people get sick with whatever infection, and they recover and they're fine," says M. Karen Newell Rogers, an immunologist at Texas A&M University School of Medicine in Temple, Texas, who studies such illnesses. "Other people get sick and recover, but they are not the same."
PANDAS is thought to be caused by antibodies generated as a result of an infection, usually strep. Normally, the antibodies fight the infection and promote healing. But in PANDAS, the antibody response is thought to go awry, attacking brain cells and resulting in OCD symptoms.
A greater understanding of the link between strep and OCD has opened the door to the study of other psychiatric or neurological illnesses that may be linked to improper immune response, including cases of autism, schizophrenia and anorexia.
"The whole area of mental illness caused by infections is being looked at more closely because of PANDAS," says Dr. Michael A. Jenike, a professor of psychiatry at Harvard Medical School and chairman of the International OCD Foundation's scientific advisory board. "If you can prevent lifelong suffering by using antibiotics or some acute intervention, that would be huge." (...)
The Hidden Potential of Autistic Kids
scientificamerican.com 30.11.2011
What intelligence tests might be overlooking when it comes to autism (...)
Researchers have long considered the majority of those affected by autism to be mentally retarded. Although the numbers cited vary, they generally fall between 70 to 80 percent of the affected population. But when Meredyth Edelson, a researcher at Willamette University, went looking for the source of those statistics, she was surprised that she could not find anything conclusive. Many of the conclusions were based on intelligence tests that tend to overestimate disability in autistic people. "Our knowledge is based on pretty bad data," she says.
This hidden potential was recently acknowledged by Laurent Mottron, a psychiatrist at the University of Montreal. In an article in the November 3 issue of Nature, he recounts his own experience working with high-functioning autistic people in his lab, which showed him the power of the autistic brain rather than its limitations. Mottron concludes that perhaps autism is not really a disease at all—that it is perhaps just a different way of looking at the world that should be celebrated rather than viewed as pathology. (...)
Her avsløres den syke hjernen
dagbladet.no 7.12.2011
Slik ser hjernen ut hos en schizofren person, vist med testen Anders Behring Breivik nekter å ta.
SYNBAR FORSKJELL: MR-bilder av to tvillinger viser hvordan personen til venstre er frisk, mens personen til høyre lider av schizofreni. Her ser man hvordan hulrommene sentralt i hjernen er større hos den syke personen. Dette er undersøkelsen Breivik har takket nei til.
(Dagbladet): Bildene på denne siden viser hvordan hjernen hos en person med schizofreni avviker fra en hjerne tilhørende en frisk person. Ifølge forskere er det åpenbare og synlige forskjeller.
- Foreløpig har MR-bilder størst anvendelse for forskning innen schizofreni. Studier viser at pasienter i gjennomsnitt har større volum av sideventriklene (hulrom sentralt i hjernen), og redusert tykkelse av hjernebarken i panne- og tinninglappene sammenlignet med friske kontrollpersoner, sier lege og forsker Ragnar Nesvåg til Dagbladet.
Han har tatt doktorgrad nettopp på MR og schizofreni, hvor dette var blant hans hovedfunn. (...)
Ifølge aktor Inga Beier Engh er det mulig å be retten pålegge Breivik å gjennomføre slike undersøkelser, gjennom straffelovens paragraf 157. Det er imidlertid et spørsmål statsadvokaten så langt ikke har vurdert. (...)
Skeptisk rettspsykolog
Rettpsykolog og forsker Pål Grøndahl er skeptisk til MR som relevant redskap i denne forbindelse.
- Man kan ikke «se» schizofreni på en MR-undersøkelse. Det blir nesten som å si at man kan «se» en personlighet på MR. På MR ser man kun fysiologiske skader og avvik. For å finne ut om de avvik som MR-bildene viser har noen som helst betydning for personen må man bruke nevropsykologiske tester for å vurdere hukommelse, evne til planlegging, resonnering, tenkning og så videre, sier Grøndahl.
Professor Ingrid Agartz er spesialist i psykiatri og mener MR-undersøkelsen bør inngå i et større og framtidsrettet studie av Breivik:
- Man bør i forlengelsen systematiskt forske på personer som har utført denne typen av handlinger for å få kunnskap som gjør at man tidlig kan identifisere risikoadferd og finne en passende behandling, sier hun til Dagbladet. (...)
Are Psychopaths “Brain Damaged”?
scientificamerican.com 6.12.2011
Pathway from the prefrontal cortex to the amygdala
We all have a ghoulish fascination with the Hannibal Lecters of this world. That’s because many of the most-publicized stories about psychopaths can be quickly banged into a Hollywood script. One of the most absorbing accounts that I’ve come across recently, however, was in an advance reading copy of a book by Paul J. Zak, due in May, called The Moral Molecule. The book, which deals largely with the hormone/neurotransmitter oxytocin and its role in social interactions, has a section on the psychopath. (...)
Could Soccer 'Headers' Cause Brain Injury?
health.yahoo.com 29.11.2011
TUESDAY, Nov. 29 (HealthDay News) -- Frequent "heading" of soccer balls by avid amateur players may cause brain damage leading to subtle but serious declines in thinking and coordination skills, a new study suggests.
For the study, researchers used an advanced MRI technique to analyze changes in brain white matter of 32 adult amateur soccer players who headed balls 436 times a year on average. Players who were high-frequency headers -- with 1,000 or more a year -- showed abnormalities similar to traumatic brain injuries suffered in car accidents, the study found.
"This is the first study to look at the effects of heading on the brain using sophisticated diffusion tensor imaging," said Dr. Michael Lipton, lead researcher and associate director of the Gruss Magnetic Resonance Research Center at the Albert Einstein College of Medicine in New York City. (...)
The Science of Stage Fright: How Stress Causes 'Brain Freeze'
healthland.time.com 28.11.2011 (Time)
When presidential candidate Rick Perry froze during a recent GOP debate — unable to remember the name of a government agency he wanted to eliminate — his brain was clearly under stress. Now new research helps explain why at moments of peak pressure, virtually all of us are vulnerable to similar failures, finding it harder to recall key words at the right time and almost impossible to focus on the task at hand.
Earlier studies have shown that under high stress, the brain tends to shut off the cortical networks involved in creativity, contemplation, planning and thinking abstractly. While that sounds like a glitch, it's actually a benefit — at least when you are facing physical threats. Taking time to consider your options is not advisable while being chased by a tiger or facing enemy fire.
As the authors of a new study in Science put it, acute stress "sharpens our senses, creates a state of fearful arousal and strengthens our memories of stressful experiences but impairs our capacity for slow deliberation." (...)
Why the Myth of the Meth-Damaged Brain May Hinder Recovery
healthland.time.com 21.11.2011 (Time)
In 2004, the New York Times ran a story about how meth use eats away brain cells, headlining it this way: "This Is Your Brain on Meth: A 'Forest Fire' of Damage." In 2005, another Times piece about the rise in foster children taken from parents who use meth noted the "particularly potent and destructive nature" of the drug and claimed that "rehabilitation for methamphetamine often takes longer than it does for other drugs." And the authors of a 2002 study on the brain-robbing effects of meth warned, based on their data, that the "national campaign against drugs should incorporate information about the cognitive deficits associated with methamphetamine."
That is, the differences in brain structure in meth users' brains didn't correlate to differences in cognitive function. Observing that people's brain structure or receptor patterns are unusual may be interesting, but it doesn't matter much unless those differences are also linked to specific problems. "It's like taking the engine of a BMW and comparing it with the engine of a Mercedes," says Hart. "The Mercedes might be bigger. But saying that means that the BMW is impaired — that's what we're doing with this imaging."
The review even takes on "meth mouth," noting that the dry mouth symptoms that have been blamed for the terrible dental problems seen in some methamphetamine users also accompany the use of legal amphetamines and some antidepressant medications. The authors write that the association between methamphetamine use and dental problems may have "less to do with pharmacological effects of methamphetamine and more to
do with non-pharmacological factors, ranging from poor dental hygiene to media sensationalism. Indeed, much of the evidence linking methamphetamine abuse and tooth
decay is anecdotal; detailed investigations of the impact of methamphetamine abuse on dental health with suitable oral health assessments are lacking."
Of course, this doesn't mean that illegal methamphetamine use is safe. And the types of studies included in the new review may still be helpful in terms of helping researchers learn more about the mechanisms of addiction and to better treat people with drug problems. "The hype and all that aside, there are still good reasons to do this research, and some findings may point the way to more novel pharmaceutical [treatments]," says Johanson.
The problem is that the hype may do serious damage to those struggling with methamphetamine problems. "One of the major reasons I did the review is that one of the most effective treatments is cognitive behavioral therapy," says Hart. "The argument has been made that these people can't benefit because they are cognitively impaired and can't pay attention. There's no scientific evidence to support that position." (...)
Narkotika knyttes til høy IQ
nrk.no 21.11.2011
Barn som fikk gode resultater på IQ-tester prøvde oftere enn andre narkotika som ungdom og voksne, viser britisk studie. Forskjellen var tydeligere for jenter enn for gutter
Smarte barn har større risiko enn andre for å bruke narkotika seinere i livet, konkluderer britisk studie. Sammenhengen er tydeligere hos jenter enn gutter. (...)
Ifølge forskerne har tidligere studier vist motsatte resultater, nemlig en sammenheng mellom høy IQ som barn og en sunn livsstil.
Noen studier har imidlertid også knyttet høy IQ-skår som barn med høyere risiko for alkoholmisbruk som voksne. Det er få som har sett på IQ og narkotikabruk. (...)
Selv om undersøkelsen korrigerer for inntekt og utdanning kan det være vanskelig å fange opp og korrigere for alle slike sosiale og kulturelle faktorer.
Pedersen peker også på en annen svakhet ved studien. Den store helseundersøkelsen som dataene er hentet fra, er basert på frivillige svar. En del av deltagerne som er fulgt fra barndommen, har falt fra før de fylte 30 og har ikke svart. Det gjør funnene til de to britiske forskerne mindre robuste. (...)
Hjernen velger vekk fakta
aftenposten.no 21.11.2011
Klimapsykologi. Det hjelper fint lite med flere fakta om klimatrusselen, så lenge folk har en enestående evne til å fornekte dem og fortsette som før. Forsker Per Espen Stoknes etterlyser nye grep i klimapolitikken. (...)
Derfor går det galt når snøen kommer
aftenposten.no 17.11.2011
Hjernen trenger tid på å skjønne at det er glatt. (...)
- Vinterkjøring er en mental overgang fra å la være å tenke på friksjon til å måtte fintenke på friksjon for å unngå uhell. Når vi setter oss bak rattet får vi alarmer og varsler om at føret ikke er slik det pleier å være, sier Moe.
Da begynner hjernen å koble om, forhåpentligvis før det skjer ulykker. (...)
Alzheimer kan oppdages i nesen
reuters.com 16.11.2011
Alzheimers sykdom lar seg oppdage på et tidlig stadium ved å granske avleiringer av eggehvite i nesen. Den nye diagnosemetoden er utviklet at forskere ved universitetet i Darmstadt i Tyskland.
Endringer i avleiringene i slimhuden i nesen avspeiler tilsvarende endringer i hjernen. Dermed kan leger hente mye kunnskap om pasientens tilstand ved å studere nesehuden, sa en av forskerne ifølge nyhetsbyrået DPA tirsdag.
- Hittil har man bare visst at de skadelige avlagringene ikke bare opptrer i hjernecellene, men også i øynenes nerveceller, forklarte professor Boris Schmidt. (...)
Når hjernen svikter
Tidsskr Nor Legeforen 2011; 131:2217 (15.11.2011)
Demens er en progredierende og dødelig hjernesykdom. Utredning og diagnostikk skjer hovedsakelig i primærhelsetjenesten. Bør det være slik?
I disse dager er det 105 år siden Alois Alzheimer (1864 - 1915) for første gang presenterte sykehistorien til den da nylig avdøde Auguste D (1850 - 1906). Kvinnen var blitt syk i 50-årsalderen, og i flere tiår etter Alzheimers beskrivelse ble tilstanden, «presenil demens», betraktet som en sjelden sykdom som kun forekom hos yngre. I løpet av 1960- og 70-årene ble det imidlertid klarlagt at amyloide avleiringer også forekommer i hjernen hos eldre med demens. Denne innsikten var viktig for å endre synet på tilstanden. Til da hadde man oppfattet det at eldre ble «rørete» som et uunngåelig naturfenomen. Denne forestillingen er ennå rotfestet, blant annet i det feilaktige uttrykket «senil» som betegnelse på den demenssyke. Alle som har opplevd utvikling av demens på nært hold, vil imidlertid være enig i at dette er noe annet enn et normalt aldersfenomen; nemlig en progredierende og dødelig hjernesykdom. (...)
Studies: Exercise helps keep the mind alert as we age
seattletimes.nwsource.com 13.11.2011
Two recent studies provide strong evidence of a correlation between exercise and better cognitive function among seniors.
If you want to keep your mind sharp as you age, make sure you exercise your body regularly.
Two recent studies provide strong evidence of a correlation between exercise and better cognitive function among seniors.
A French study of 2,809 women conducted over five years confirmed that the women who got daily exercise equivalent to a brisk 30-minute walk are less likely to have cognitive impairment than the women who exercised less or not at all. The impairment means problems with memory, language, thinking and judgment.
A Canadian study of 197 seniors with an average age of 74.8 used a more precise measurement of physical activity: active energy expenditure. (AEE is defined as 90 percent of total energy expenditure, minus resting metabolic rate.) When their data was adjusted for other variables, those with the highest AEE were the least likely to suffer from cognitive impairment.
Both studies were published in the Archives of Internal Medicine in July to coincide with an international conference on Alzheimer's that was held in Paris that month. (...)
Study: Autistic Children Have More Brain Cells
healthland.time.com 9.11.2011 (Time)
There's growing evidence that the brains of autistic children are very different from the brains of other youngsters. Now a new study that found an excess of brain cells in children with autism comes closer to pinpointing the origins of the condition: in utero versus in toddlerhood.
In research reported in the Journal of the American Medical Association (JAMA), scientists at the University of California, San Diego, found that autistic children have about 67% more nerve cells in a part of the brain known as the prefrontal cortex than children without autism. The prefrontal cortex is involved in processing social skills, communication, cognitive functions and language — all areas in which autistic children often show abnormal development. (...)
Autistic Children May Have Too Many Brain Cells
health.yahoo.com 8.11.2011
TUESDAY, Nov. 8 (HealthDay News) -- The brains of autistic children have far more neurons in the prefrontal cortex than the brains of kids without autism, finds a new study that could advance research into the disorder.
"For the first time, we have the potential to understand why autism gets started," said study author Eric Courchesne, a professor of neurosciences at the University of California, San Diego School of Medicine and director of the Autism Center of Excellence.
"Creating brains cells and the correct number of brain cells is absolutely fundamental to building the brain," said Courchesne. "If there is an excess number of neurons, there must be a negative consequence to that in the way the brain gets wired or organized."
In this small, preliminary study, the researchers examined postmortem brain tissue from seven boys with autism and six boys without autism who were aged 2 to 16 when they died. (...)
How Does Our Brain Learn New Information?
sciencedaily.com 8.11.2011
Heidi Johansen-Berg, a neuroscientist at the University of Oxford, responds:
the brain is an enormously complex network of billions of neurons connected by more than 90,000 miles of fibers—long enough to traverse Russia’s coastline four times. This intricate architecture allows us to absorb information quickly and efficiently. Learning mainly takes place at synapses, the junctions between neurons where information is relayed. A synapse’s performance changes when we learn something new, obeying the principle that “cells that fire together, wire together.” (...)
Brain analysis can help predict psychosis: study
reuters.com 26.10.2011
(Reuters) - Computer analysis of brain scans could help predict how serious or long term a psychotic patient's illness may become and help doctors make more accurate decisions about how best to treat them, researchers said on Monday.
In a study in the journal Psychological Medicine, scientists from King's College London's Institute of Psychiatry and University College London's computer science department found that using computer algorithms to analyze MRI (magnetic resonance imaging) brain scans can predict a patient's outcome.
"This is the first step toward being able to use brain imaging to provide tangible benefit to patients affected by psychosis," said Paola Dazzan of King's, who co-led the study.
She said this could in future lead to a quick reliable way of predicting how a patient's illness will develop, allowing doctors to give the best treatments to those most in need and avoid giving long courses of antipsychotic drugs to people with only very mild forms of psychosis.
Psychosis is a condition that affects people's minds, altering the way they think, feel and behave. It can also be accompanied by hallucinations and delusions.
The most common forms of psychosis are part of mental illnesses such as schizophrenia -- which affects around 24 million people worldwide -- and bipolar disorder, but psychotic symptoms can also occur in conditions like Parkinson's disease and alcohol or drug abuse. (...)
Heart procedures linked to cognitive decline (Hjerteinngrep linket til kognitiv svekkelse)
reuters.com 4.11.2011
(Reuters Health) - In a new study of German heart patients, people who had invasive bypass surgery and those who underwent less-invasive stent placement showed declines in thinking and memory skills a few months after the procedures.
Doctors have long been concerned about cognitive decline in patients who undergo coronary artery bypass grafting (CABG) because of blocked arteries, and indeed, memory deficits were more significant after those procedures than after stenting.
Still, the findings don't prove it's the procedures themselves that cause memory decline -- it could just be that plaque buildup in blood vessels in both the heart and the brain is causing a variety of problems in the same patients.
"These patients obviously all have atherosclerosis," said Dr. Mark Newman, who studies cognitive decline after cardiac surgery at the Duke University Medical Center in Durham, North Carolina.
"If you have atherosclerosis in your coronary vessels, you probably have it in other vessels in your body as well."
Patients who are treated with CABG are often in a worse health state, with more buildup, than those who undergo stenting. It could be that "cognitive decline after these procedures more relates to the severity of the atherosclerosis than the procedure itself," Newman, who wasn't involved in the new research, told Reuters Health. "I think that's still a debate."
Even so, it makes sense that when built-up cholesterol in heart vessels is nudged loose during surgery, it could travel to the brain and cause problems there, researchers said. (...)
Understanding the Human Brain
EDITORIAL
Summary
Like most fields in biology, neuroscience is succumbing to an “epidomic” of data collecting. There are major projects under way to completely characterize the proteomic, metabolomic, genomic, and methylomic signatures for all of the different types of neurons and glial cells in the human brain. In addition, “connectomics” plans to provide the complete network structure of brains, and “synaptomics” aims to uncover all molecules and their interactions at synapses. This is a good time to pause and ask ourselves what we expect to find at the end of this immense omic brainbow. (...)
Exercise and Genetic Rescue of SCA1 via the Transcriptional Repressor Capicua
Science 2011;334(6056): 690-693 (4 November)
Abstract
Spinocerebellar ataxia type 1 (SCA1) is a fatal neurodegenerative disease caused by expansion of a translated CAG repeat in Ataxin-1 (ATXN1). To determine the long-term effects of exercise, we implemented a mild exercise regimen in a mouse model of SCA1 and found a considerable improvement in survival accompanied by up-regulation of epidermal growth factor and consequential down-regulation of Capicua, which is an ATXN1 interactor. Offspring of Capicua mutant mice bred to SCA1 mice showed significant improvement of all disease phenotypes. Although polyglutamine-expanded Atxn1 caused some loss of Capicua function, further reduction of Capicua levels—either genetically or by exercise—mitigated the disease phenotypes by dampening the toxic gain of function. Thus, exercise might have long-term beneficial effects in other ataxias and neurodegenerative diseases. (...)
Nervestøy blokkerer hørselen
uib.no 27.10.2011
Postdoktor Kristiina Kompus sammenlignet all forskning med hjerneskanner som er utført på hørselshallusinasjoner. Hun er medlem av fMRI-gruppen i Bergen og forsker i Kenneth Hugdahls ERC-prosjekt. (...)
. Dette så forskere ved fMRI-gruppen ved Det psykologiske fakultet da de sammenlignet hjerneskanninger fra personer med hørselshallusinasjoner.
– Når vi hører stemmer blir et bestemt senter i hjernen aktivt. Våre studier viser at det samme senteret blir aktivt når schizofrene hører indre stemmer, sier postdoktor Kristiina Kompus ved Institutt for biologisk og medisinsk psykologi.
– Men når hjernen reagerer på stemmer som ikke er der, reagerer den ikke på lyder som kommer utenfra, fortsetter hun.
Kompus kom frem til dette etter å ha gjennomført en såkalt meta-analyse. Det vil si at hun samlet all tidligere forskning på feltet og studerte hva som er felles for disse. Resultatene er blir i disse dager publisert i det anerkjente tidsskriftet Neuropsychologia.
Støy i hodet
Ifølge Kompus virker det som om de indre stemmene produserer en form for nevralt støy som blokkerer for stemmer som kommer utenfra. Det kan også være at de indre stemmene hindrer ytre signaler å nå frem til de sentrene i hjernen som behandler stemmer. (...)
Ved funksjonell hjerneskanning i en fMRI-maskinen kan forskere se hvilke funksjoner, strukturer og forbindelser som er aktiverti sving i hjernen når man hører stemmer som både kommer innenfra og utenfra. Det røde feltet viser hvor hjernen blir aktivert når man hører stemmer i hodet eller utenfra.
(Illustrasjon: Bergen fMRI-group).
Vil isolere stemmer
Det er ingen som vet hvordan stemmene oppstår. Kompus sier at det virker som om hørselssenteret i hjernen som er aktivt når man hører både indre og ytre stemmer, selv produserer stemmene. Det kan også være at det mentale kontrollsenteret som behandler sanseinntrykk er ute av kontroll og omgjør nevralt støy i hjernen til stemmer. I tillegg er sannsynligvis det mentale kontrollsenteret i pannelappene satt ut av spill slik at de indre stemmene ikke blir dempet.
For å finne ut hvordan stemmene oppstår skal Kompus skanne hjernen til mentalt friske personer som hører stemmer. Det er nemlig ikke bare schizofrene som hører indre stemmer, men også friske personer som fungerer normalt i hverdagen. Disse personene er Kompus spesielt interessert i å forske på fremover.
– Hos mentalt friske personer kan man isolere stemmeforstyrrelsen og dermed ha større sjanse for å finne ut hva stemmene skyldes, sier Kristiina Kompus. (...)
Autism går att se på ansiktsformen
dn.no 21.10.2011
Autism går att se på ansiktsformen hos barn med funktionsstörningen, visar ny forskning. Resultaten kan innebära att forskarna har kommit närmare lösningen på hur autism uppstår.
– I dag vet vi inte om autism är ärftligt eller den orsakas av miljöfaktorer, säger professor Kristina Aldridge som har lett studien vid University of Missouri i USA till tidningen News Medical.
Människans huvud och den mänskliga hjärnan växer parallellt och processen startar redan hos embryot. Sedan fortsätter utvecklingen vartefter barnet växer till tonåren. (...)
Skiftjobb som ung ökar risken för ms
testfakta.se 18.10.2011
Personer som arbetar skift redan i unga år riskerar i högre utsträckning än andra att drabbas av multipel skleros, ms. De tonåringar som arbetar skift i mer än tre år före de fyllt 20 år löper dubbelt så stor risk att drabbas av den neurologiska sjukdomen.
Det visar två svenska studier med totalt nära 14.000 personer som gjorts oberoende av varandra, och som publicerats i tidningen Annals of Neurology.
Det är oklart varför tonåringar är extra känsliga, men troligtvis beror det på sömnhormonet melatonin, enligt läkaren och forskaren Anna Karin Hedström vid Karolinska institutet.
- Om man jobbar skift får man en störning i den biologiska klockan. Det är också väl visat att skiftarbetare har en sämre sömn än andra, och båda dessa saker påverkar immunförsvaret på ett sätt som kan leda till ms senare i livet, säger hon till SR Ekot.
Äldre person som jobbar oregelbundna tider löper ingen utökad risk att drabbas av sjukdomen, som innebär att det egna immunförsvaret bryter ned nervsystemet. (...)
Good news about the ageing brain
BMJ 2011; 343:d6288 (17 October)
Important cognitive skills decline with age, but we retain a considerable mental richness in later life, say Marcus Richards and Stephani Hatch (...)
Cognitive ageing is not all bad
First we must acknowledge that cognitive ageing is not a simple or single entity. The evidence leaves no doubt that the intentional recall of detailed information bound to time and place is sensitive to age related decline.3 So is the kind of information processing necessary for complex multitasking. Yet memory for more abstract information, such as general knowledge or the meaning of words, is relatively well preserved and may actually improve as we age.4 Older people may be less able to remember specific details in a passage of text than younger people but are as good or better at understanding its gist5—important for competence in communication, if vulnerable to distortion. Or turning to everyday practical tasks that draw on cognitive skills, such as driving or adhering to drug treatment, these tend to be preserved when they are based on the development of expertise or supported by routine and familiarity.6 Even skills that seem to epitomise the challenge of ageing in the modern world, such as mastering information technology, can be learnt to a high degree of accuracy by older people, albeit more slowly than by younger adults.7 (...)
Styrer kunstig arm med tankene
nrk.no 14.10.2011
Tim Hemmes ble lam for sju år siden, nå rører han kjæresten med ei kunstig arm styrt av hjerneaktivitet.
30 år gamle Hemmes ble lam fra halsen og ned etter en motorsykkelulykke i 2004.
Gjennom et prøveprosjekt som benytter seg av såkalt BCI (brain-computer interface), har Hemmes nå klart å kontrollere en ekstern mekanisk arm ved hjelp av tankekraft. (...)
Winning May Take All Your Brain Power
health.yahoo.com 7.10.2011
FRIDAY, Oct. 7 (HealthDay News) -- Nearly your entire brain is engaged in striving for success when you play games, according to a new study.
The finding that many more brain regions besides the reward centers activate in an attempt to win games, such as rock-paper-scissors, makes sense in terms of evolution, the Yale University researchers noted.
"Our brain functions to maximize the chance of survival and reproduction, so reward should be important for all cognitive functions, and thus most brain regions," lead author Timothy Vickery, a postdoctoral fellow in the psychology department, said in a university news release.
He and his colleagues used a special pattern analysis technique to examine functional MRI scans of volunteers as they won and lost games. The results showed that wins and losses were recognizable in nearly all areas of the brain.
The study appears in the Oct. 6 issue of the journal Neuron. (...)
Half Asleep
scientificamerican.com 3.10.2011
Deprived of rest, parts of the brain start to snooze
Ever stay up so late you feel like parts of your brain are falling asleep? They might be. In the April 28 issue of Nature, researchers used too-fun-to-resist toys to keep rats up for hours longer than usual, measuring electrical activity in the rodents’ brains with tiny implanted wires. Although the animals remained active, with most brain cells firing as erratically as they normally do in alert animals, small groups of neurons began flipping over to a sleeplike state, becoming electrically silent before firing in unison. Trained rats lost the knack for food-nabbing tricks as neurons in learning-related brain regions dozed off, perhaps explaining some of the deteriorating dexterity, flagging attention and questionable judgment seen in humans who are sleep-deprived. (...)
Europe's brain disorder bill hits 800 billion euros (Regningen for hjernelidelser i Europa kommer opp 800 milliarder euro)
reuters.com 4.10.2011
(Reuters) - The annual cost of brain disorders in Europe has soared to 798 billion euros ($1 trillion) and the region is facing a political, social and financial "ticking bomb" as more people fall prey to mental illnesses, researchers said on Tuesday.
study by the European Brain Council (EBC) said the bill for disorders such as depression, anxiety, insomnia and dementia, will rise as people live longer, making it "the number one economic challenge for European health care."
The cost projection comes in the wake of a study last month that found that Europeans are plagued by mental and neurological illnesses with almost 165 million people, or 38 percent of the European Union population, suffering each year.
The 798 billion euro figure -- which equates to 1,550 euros ($2,000) per person in Europe -- is more than double the estimate made by a previous EBC study, published in 2005.
"The increasing burden and the associated increasing cost of disorders of the brain is a ticking bomb under the European economy and the EU society as a whole," said the report by experts in Britain, Germany, Italy, Sweden and across Europe.
They called for a major increase in research funding and resources to help fend off the threat.
Some big drug companies, in Europe particularly GlaxoSmithKline and AstraZeneca, have been backing away from investment into research on how the brain works and affects behavior, putting the onus on governments and health charities to stump up funding for neuroscience. (...)
Can drugs drill holes in your brain? (Kan legemidler drille hull i hjernen din?)
blogs.scientificamerican.com 29.9.2011
The idea of drugs tunneling their way through the brain, worms to the mind’s apple, is a frequent metaphor I hear. I wrote on the topic for Discovery’s Curiosity and resurfaced it to prepare material for drug education talks with high schoolers. Here’s a simple look back at the common question, which never fails to remind me just how complex, yet undeniably vulnerable, our brains are:
Drugs may not drill holes actual holes through your brain, but they can turn your mental processing powers into Swiss cheese. Here’s how it works: the brain is filled with different kinds of neurotransmitters, or cells that ferry information. They make our nervous system run and function normally. A good example is a neurotransmitter called dopamine, which fills many roles in the brain, including your motivation, cognition and punishment/reward systems.
Neurotransmitters like dopamine shuttle around and bind to specific receptors to communicate messages in the brain. Drugs can wreak havoc on this system in several ways – they may commit the cellular equivalent of a hostage situation and bind to receptors in the place of neurotransmitters. If this happens, neurotransmitters can’t enter or exit their receptors, and parts of your nervous system can’t communicate with your brain. Worse yet, they can thwart the chemical reactions that create neurotransmitters, your electrical messaging, in the first place. They also may overstimulate or block receptors so that neurotransmitters can’t deliver their messages.
If flooded or blocked, your neuron receptors can become desensitized or oversensitized to neurotransmitters like dopamine. This means your brain isn’t recognizing or receiving the information needed to work your crucial parts of your nervous system, like those that control your emotional or motivation structures. Ultimately, you have “holes” in different parts of your mental systems, and which exact parts depend upon the kind of drug you take.
Here’s a video illustrating the concept from BBC’s “How Drugs Work” series, describing cocaine’s influence on the brain’s dopamine. (...)
Mild Strokes May Have Hidden Effects (Milde hjerneslag kan ha skjulte effekter)
health.yahoo.com 29.9.2011
MONDAY, Oct. 3 (HealthDay News) -- Even mild strokes can result in serious but unrecognized disabilities, such as depression, vision problems and difficulty thinking, according to a new study.
The findings, released Monday at the Canadian Stroke Congress in Ottawa, suggest new guidelines are needed on the treatment and management of mild strokes, the researchers said.
"There is no such thing as a mild stroke," said study co-author Annie Rochette, of the University of Montreal, in a news release from the Heart and Stroke Foundation of Canada. "These patients face huge challenges in their daily lives."
After interviewing 200 stroke victims within six weeks of having their first stroke, the researchers found a high rate of sleeplessness and depression among the participants. Nearly 25 percent were clinically depressed. The stroke patients also reported a significant drop in their perceived quality of life, the study revealed.
The researchers said treatment for symptoms of depression, such as fatigue, loss of appetite, lack of concentration, disturbed sleep and thoughts of suicide, should be an important part of recovery for mild stroke patients. (...)
Psykopatiske sjefer
ukeavisenledelse.no 29.9.2011
Psykopater kjennetegnes av at de mangler moral, er egoistiske og mest opptatt av egen makt og egne fornøyelser.
Andelen psykopater blant ledere kan være fire ganger større enn i befolkningen ellers.
Det skriver Time Healthland, som omtaler et forskningsprosjekt gjort av psykolog og ledercoach Paul Babiak.
Babiak har studert 203 talenter i amerikanske virksomheter som er blitt håndplukket til å delta i et lederutviklingsprogram, og resultatene viser at en av 25 ledere – det vil si fire prosent – kan være psykopater. Dette skal være fire ganger flere enn andelen psykopater i befolkningen generelt.
Psykopater kjennetegnes av at de mangler moral, er egoistiske og mest opptatt av egen makt og egne fornøyelser. De har også en tendens til å være sjarmerende, men manipulerende.
Når de tiltrekkes av næringslivet, kan det være fordi de fristes av jaget etter økonomiske resultater i et miljø hvor grådighet ofte blir akseptert.
Babiak har i studien sin brukt en metode for å psykopatiske trekk som er utviklet av Robert Hare fra University of British Columbia i Canada.
Les mer om destruktivt lederskap i norske virksomheter her: Ukeavisen Ledelse nr. 31 2011 (...)
Ny metode for å scanne hjerner
aftenposten.no 29.9.2011
Forskere ved SLAC National
Accelerator Laboratory ved Stanford
University i California utviklet
en ny og raskere metode for å
scanne gamle manuskripter, slik
at man kunne få frem tekst som
var overskrevet i senere perioder.
Nå viser det seg at denne teknikken
også kan brukes til å
scanne menneskehjerner og dermed
bli et hjelpemiddel for å behandle
personer som er rammet
av slag eller andre former for
hjerneskade. Metoden gir et mer
detaljert bilde av blødninger i
hjernen enn vanlig MR-scanning.
Den avdekker også hvordan jern
og andre metaller er fordelt.
Hittil har man bare scannet deler
av menneskehjerner, men
målet er å kunne bruke metoden på pasienter, fremgår det av
hjemmesidene til Stanford. (...)
Low Vitamin B12 Linked to Smaller Brains and Cognitive Decline (Lave verdier av B12 linket til mindre hjerner og kognitiv svekkelse)
healthland.time.com 26.9.2011 (Time)
Older people may not be getting enough vitamin B12, and that could affect their thinking and the size of their brain, according to a new study.
For the research published in the journal Neurology, scientists led by Christine Tangney, an associate professor of clinical nutrition at Rush University Medical Center, followed a group of 121 people aged 65 or older for 4.5 years. The researchers measured the participants' blood levels of vitamin B12 and markers of its breakdown products. They also recorded people's performance on tests of thinking skills and took MRI scans of their brains.
The researchers found that low levels of vitamin B12 were linked to smaller brain volumes and lower scores on cognitive tests. Vitamin B12 is critical for normal red blood cell formation, as well as for producing other agents important for maintaining healthy DNA, hormones, proteins and fats the body needs. (...)
Could Too Little Vitamin B-12 Shrink the Aging Brain?
nlm.nih.gov 26.9.2011
Deficiency may affect thinking skills, but not enough evidence to advise supplements, experts say
MONDAY, Sept. 26 (HealthDay News) -- Too little vitamin B-12 may be associated with smaller brain size and more problems with thinking skills as people age, new research suggests.
And the number of people who suffer from B-12 deficiencies may be greater than thought because current methods for measuring levels of the vitamin may not be accurate, said Christine C. Tangney, lead author of the study published in the Sept. 27 issue of Neurology. The study was funded by the U.S. National Institute on Aging.
The researchers assessed the study participants' vitamin levels not only from B-12 levels themselves, but from blood metabolites that are considered markers of B-12 activity (or lack of it) in the tissues.
But the findings aren't nearly enough to start recommending people take B-12 supplements to jumpstart their brains, cautioned Dr. Marc L. Gordon, chief of neurology of Zucker Hillside Hospital in Glen Oaks, N.Y. Gordon was not involved with the study.
"It's not clear exactly if you have a measurement like this whether it's causal or that lowering the marker will drive a change in the risk," he said.
And unless you're a strict vegan, most people do get enough B-12, which is critical for brain health, from their diet -- mainly from animal-derived products, added Gordon, who is also an Alzheimer's researcher at The Feinstein Institute for Medical Research in Manhasset, N.Y. (...)
tudy: 1 in 25 Business Leaders May Be Psychopaths (Studie: 1 av 25 forretningsledere kan være psykopater)
healthland.time.com 20.9.2011 (Time)
One in 25 bosses may be psychopaths — a rate that's four times greater than in the general population — according to research by psychologist and executive coach Paul Babiak.
Babiak studied 203 American corporate professionals who had been chosen by their companies to participate in a management training program. He evaluated their psychopathic traits using a version of the standard psychopathy checklist developed by Robert Hare, an expert in psychopathy at the University of British Columbia in Canada.
Psychopaths, who are characterized by being completely amoral and concerned only with their own power and selfish pleasures, may be overrepresented in the business environment because it plays to their strengths. Where greed is considered good and profitmaking is the most important value, psychopaths can thrive. (...)
In fact, it can be hard spot the psychopath in any crowd (according to Hare, psychopaths make up 1% of the general population). They're not all ruthless serial killers; rather, psychopaths who grow up in happy, loving homes might end up channeling their energies in a less violent way — say, by becoming a CEO. "Psychopaths really aren't the kind of person you think they are," Babiak said. (...)
(Anm: Corporate psychopathy: Talking the walk. Behav Sci Law. 2010 Mar-Apr;28(2):174-93.)
Corporate psychopathy: Talking the walk
Behav Sci Law. 2010 Mar-Apr;28(2):174-93
Abstract There is a very large literature on the important role of psychopathy in the criminal justice system. We know much less about corporate psychopathy and its implications, in large part because of the difficulty in obtaining the active cooperation of business organizations. This has left us with only a few small-sample studies, anecdotes, and speculation. In this study, we had a unique opportunity to examine psychopathy and its correlates in a sample of 203 corporate professionals selected by their companies to participate in management development programs. The correlates included demographic and status variables, as well as in-house 360 degrees assessments and performance ratings. The prevalence of psychopathic traits-as measured by the Psychopathy Checklist-Revised (PCL-R) and a Psychopathy Checklist: Screening Version (PCL: SV) "equivalent"-was higher than that found in community samples. The results of confirmatory factor analysis (CFA) and structural equation modeling (SEM) indicated that the underlying latent structure of psychopathy in our corporate sample was consistent with that model found in community and offender studies. Psychopathy was positively associated with in-house ratings of charisma/presentation style (creativity, good strategic thinking and communication skills) but negatively associated with ratings of responsibility/performance (being a team player, management skills, and overall accomplishments). (...)
Håp om tinnitus-kur
nrk.no 15.9.2011
Hodetelefoner og høy lyd fra konserter kan gi deg ørersus.
Tinnitus kan skyldes endringer i hjernen etter hørselskade, for eksempel fra høy konsertlyd. Men en kur kan trolig være underveis. (...)
Inne i hjernen
Men selv tinnitus blir utløst av høy lyd eller skader i det ytre øret, finnes selve mekanismen som lager lydene ikke her. Den finnes inne i selve hjernen.
Det hevder i alle fall en gruppe forskere ved Berkeley-universitetet i California. Og de mener også at de har en mulig kur.
– Vi hører med andre ord med hjernen, og ikke med ørene! sier Kari Jorunn Kværner.
Hun er professor ved Det medisinske fakultet ved Universitetet i Oslo, og meget interessert i ører og hørsel, og ikke minst behandlingen av tinnitus.
– Studien er interessant. Forfatterne kommer med en forsiktig konklusjon om at dersom man lykkes i å finne medikamenter, kan det kanskje redusere opplevelsen av tinnitus, fortsetter hun. (...)
Homo sapiens har haft sex med de fleste
b.dk 8.9.2011
Der er stadig større tvivl om, at vi reelt udkonkurrerede neanderthalerne, så de uddøde. Det ser ud til, at vi snarere opkøbte virksomheden og videreførte en del af den. Herunder måske generne for rødt hår og hvid hud, som neanderthalerne ser ud til at have haft. Og i hvert fald en række immunforsvarsgener, som har tjent os godt.
Det moderne menneske har blandet DNA med fremmede og nu uddøde menneskearter gennem hele vores udviklingshistorie.
Det er artige sager, vi finder ud af om vores forfædre for tiden: Så snart den moderne menneskehed kom ud af Afrika, havde vi sex med fremmede - og nu uddøde - underarter af fortidsmennesker. Og nu viser det sig, at Homo sapiens heller ikke holdt sig tilbage i tidligere tider. (...)
Det skete i Europa og det vestlige Asien, fra vi for 65.000 år kom ud af Afrika og bredte os over resten af verden, indtil neanderthalerne forsvandt for 30.000 år siden. Om de skal anses for uddøde eller optagne i menneskeslægten diskuteres stadig. (...)
Nogle mennesker i dag har op til fire procent neanderthal-DNA, mens denisovaerne har afsat et aftryk på op til seks procent af DNAet i et moderne menneske, siger amerikanske forskere, der netop har vist, at en stor del af vores immunforsvar kan vi faktisk takke neanderthalerne og denisovaerne for. (...)
Brain burdens
Nature 2011;477:132 (08 September)
Europe's shocking statistics on neurological and mental disorders demand a shift in priorities.
Research to combat diseases, one would think, would be funded in proportion to the burden inflicted on the population. The reality is very different — witness the disparity between the huge burden caused by diseases in the developing world and the scant resources for research to tackle them.
Another disparity exists, and it is universal: the significant burden of mental and neurological illnesses of the human brain compared with the small proportion of research funds available to understand and treat them. Unlike cardiovascular disease and cancer, in most cases the burdens of brain disorders tend to manifest themselves in disabilities and in effects on the lives of the people afflicted and their carers, rather than in early deaths. That makes the footprint of these conditions harder to quantify.
So it is particularly valuable that a group of brain specialists and statisticians has produced a new quantification of the burden of brain disorders across 30 European countries. Building on a previous study, they assessed more disorders, analysed the literature and consulted national experts to validate emerging perspectives. The result? A conservative estimate that, in a typical year, about 165 million people — 38% of the total population of these countries — will have a fully developed mental illness (H. U. Wittchen et al. Eur. Neuropsychopharmacol. 21, 655–679; 2011).
The shocking statistics don't end with prevalence. A good measure of disease burden is the disability-adjusted life year (DALY) — the person-years lost in a population owing to disability and shortened life. The authors establish brain disorders — both mental and neurological — as the greatest health burden on the population, comprising 23.4% of all DALYs among men and 30.1% for women. (...)
Yoghurt kan motvirke angst og depresjon
nrk.no 5.9.2011
Forskning tyder på at melkesyrebakterier kan virke positivt på hjernen vår.
Mus som ble foret med melkesyrebakterier viste færre tegn på angst og depresjon enn andre mus. Forskerne tror at disse bakteriene også kan virke inn på hvordan vi mennesker har det.
Når enkelte yoghurtprodukter lover å holde magen sunn, er det fordi de inneholder såkalt gode bakterier, som bidrar til å holde tarmfloraen i balanse.
Probiotika, også kalt melkesyrebakterier, har en positiv fysiologisk effekt fordi de kan utkonkurrere potensielt skadelige bakterier i tarmen.
Etter å ha undersøkt hvordan bakterien Lactobacillus rhamnosus JB-1 påvirker sentralnervesystemet hos mus, lurer en gruppe irske og kanadiske forskere nå på om disse bakteriene også kan virke inn på hvordan vi mennesker har det psykisk.
Ifølge studien deres ga tilførsel av Lactobacillus rhamnosus blant annet et signifikant lavere nivå av stresshormonet kortikosteron hos musene. (...)
Strokes Rising Among Teens, Young Adults: CDC (Hjerneslag øker blant tenåringer, unge voksne: CDC)
healthland.time.com 1.9.2011 (Time)
THURSDAY, Sept. 1 (HealthDay News) -- Strokes are on the rise among teens and young people, a new government report shows.
The number of people aged 15 to 44 hospitalized for stroke jumped by more than third between 1995 and 2008, say researchers from the U.S. Centers for Disease Control and Prevention. The increase may be due partly to the increasing numbers of young people who have diseases such as high blood pressure and type 2 diabetes -- diseases usually associated with older adults, they added.
High blood pressure, smoking, diabetes, obesity and high cholesterol are all risk factors for stroke, the researchers noted. (...)
Glutamatergic and Dopaminergic Neurons Mediate Anxiogenic and Anxiolytic Effects of CRHR1
Science 2011 (Published Online September 1 2011)
Abstract The corticotropin-releasing hormone receptor 1 (CRHR1) critically controls behavioral adaptation to stress and is causally linked to emotional disorders. Using neurochemical and genetic tools, we determined that CRHR1 is expressed in forebrain glutamatergic and GABAergic as well as in midbrain dopaminergic neurons. Via specific CRHR1 deletions in glutamatergic, GABAergic, dopaminergic and serotonergic cells, we found that the lack of CRHR1 in forebrain glutamatergic circuits reduces anxiety and impairs neurotransmission in amygdala and hippocampus. Selective deletion of CRHR1 in midbrain dopaminergic neurons increases anxiety-like behavior and reduces dopamine release in the prefrontal cortex. These results define a bidirectional model for the role of CRHR1 in anxiety and suggest that an imbalance between CRHR1-controlled anxiogenic glutamatergic and anxiolytic dopaminergic systems might lead to emotional disorders. (...)
Tarmens bakterier påverkar hjärnan
sverigesradio.se 2.9.2011
Bakterier från yoghurt gjorde mössen lugnare
Bakterier i magen kan påverka hjärnan och beteendet åtminstone hos djur, det här bekräftas i en ny studie. Det handlar om möss som blev lugnare och mindre stressade när de fick äta bakterier som finns i yoghurt.
Nu en nyhet som är kopplad till morgon-yoghurten. Bakterier i magen kan påverka hjärnan och beteendet åtminstone hos djur, det här bekräftas i en ny studie. Det handlar om möss som blev lugnare och mindre stressade när de fick äta bakterier som finns i yoghurt.
Den bakterie det handlar om finns i en del yoghurtsorter med tillsatt bakteriekultur, den heter lactobacillus rhamnosus - fast mössen i experimentet fick den serverad i en buljong istället.
När sen mössen hade ätit bakterien under en månad undersökte de amerikanska forskarna hur de betedde sig i olika test. Och man kunde då se att mössen var mindre stressade och lugnare. Det verkar alltså som om bakterierna påverkade mössens beteende.
Forskarna tror att en kopplingen mellan bakterierna och beteendet kan vara vagus-nerven, en nerv som går från tarmarna upp till hjärnan. När forskarna undersökte möss som hade ätit bakterierna, men som fått sin vagus-nerv avskuren såg de inga effekter av bakterierna.
Det här är en av flera studier som under det senaste året har undersökt kopplingen mellan bakterier i tarmen och hjärnan. Tidigare i år visade svenska forskare att tarmens bakterier kan påverka hjärnans utveckling hos möss. Sven Pettersson, professor vid Uppsala Universitet, var en av forskarna bakom den studien, och enligt honom bekräftar den nya studien att bakterier i tarmen kan påverka både beteendet och hur hjärnan fungerar.
- Det här är ett jätteroligt tillskott, för det pekar ju på att finns en kommunikation mellan bakterierna i tarmen och vad de gör där och hjärnan, och det här är jättespännande.
Än så länge är studierna gjorda på möss, men forskarna bakom den nya studien tror att det kan finnas en liknande effekt hos människor, och att det här kanske kan bli ett nytt sätt att behandla sjukdomar som är kopplade till stress.
Antibiotic overuse: Stop the killing of beneficial bacteria
Nature 2011;476: 393–394 (25 August)
Concerns about antibiotics focus on bacterial resistance — but permanent changes to our protective flora could have more serious consequences, says Martin Blaser. (...)
Genene dine avgjør hvor smart du blir
dagbladet.no 1.9.2011
Som om ikke midtlivskrisa var nok — med dårlige gener blir du dummere fra du fyller 50.
(Dagbladet): Ny forskning viser at inntil halvparten av variasjonene i intelligens avgjøres av genene dine. Forskerne mener å ha kommet et skritt nærmere å fastslå hvor viktig arv er for intelligensen.
- Debatten om arv og miljø har vært langvarig, men nå har vi klart å vise hvor viktige genene faktisk er, seier Stéphanie Le Hellard, seniorforskar ved Universitetet i Bergen til forskning.no. (...)
Telomere Dysfunction–Related Serological Markers Are Associated With Type 2 Diabetes
Diabetes Care 2011 (Published online before print August 26)
OBJECTIVE Recent studies have identified a set of serological markers for telomere dysfunction and DNA damage. The relevance of these serological markers in type 2 diabetes remains elusive. We investigated the association of serological markers (EF-1α, stathmin, and N-acetyl-glucosaminidase) with leukocyte telomere length, a functional variant of uncoupling protein-2 (UCP2), and susceptibility of type 2 diabetes. (...)
CONCLUSIONS Serological N-acetyl-glucosaminidase, telomere length, and the UCP2–886G>A variant are independent risk factors for type 2 diabetes. Serological N-acetyl-glucosaminidase correlates with telomere length but not with the UCP2–886G>A variant. (...)
(Anm: Serological; serological-test (britannica.com).)
Working Moms Who Accept That They 'Can't Do It All' Suffer Less From Depression (Kvinner i arbeidslivet som som aksepterer at de "ikke kan gjøre alt" lider i mindre grad av depresjon)
medicalnewstoday.com 22.8.2011
Working moms have lower rates of depression than their stay-at-home counterparts, but buying into the supermom myth could put working mothers at greater risk for depression.
A new study shows that working mothers who expressed a supermom attitude that work and home lives can be blended with relative ease showed more depression symptoms than working moms who expected that they would have to forego some aspects of their career or parenting to achieve a work-life balance.
"Women are sold a story that they can do it all, but most workplaces are still designed for employees without child-care responsibilities," said Katrina Leupp, a University of Washington sociology graduate student who led the study. In reality, juggling home and work lives requires some sacrifice, she said, such as cutting back on work hours and getting husbands to help more.
"You can happily combine child rearing and a career, if you're willing to let some things slide," Leupp said. She presented her study Aug. 21 at the American Sociological Association's annual meeting in Las Vegas, Nev. (...)
Good Ruminations Or Bad Ruminations In The Depressed Brain? (God grubling eller dårlig grubling i den depressive hjerne?)
medicalnewstoday.com 23.8.2011
All of us, at times, ruminate or brood on a problem in order to make the best possible decision in a complex situation. But sometimes, rumination becomes unproductive or even detrimental to making good life choices. Such is the case in depression, where non-productive ruminations are a common and distressing symptom of the disorder. In fact, individuals suffering from depression often ruminate about being depressed. This ruminative thinking can be either passive and maladaptive (i.e., worrying) or active and solution-focused (i.e., coping). New research by Stanford University researchers, published in Elsevier's Biological Psychiatry, provides insights into how these types of rumination are represented in the brains of depressed persons. (...)
Can The Brain's Reaction To Sadness Predict A Person's Risk For Future Depression?
medicalnewstoday.com 23.8.2011
Depression is increasingly recognized as an illness that strikes repeatedly over the lifespan, creating cycles of relapse and recovery. This sobering knowledge has prompted researchers to search for markers of relapse risk in people who have recovered from depression. A new paper published in Elsevier's Biological Psychiatry suggests that when formerly depressed people experience mild states of sadness, the nature of their brains' response can predict whether or not they will become depressed again. (...)
"Despite achieving an apparent recovery from the symptoms of depression, this study suggests that there are important differences in how formerly depressed people respond to emotional challenges that predict future well-being," explained author Dr. Norman Farb. "For a person with a history of depression, using the frontal brain's ability to analyze and interpret sadness may actually be an unhealthy reaction that can perpetuate the chronic cycle of depression."
Dr. John Krystal, editor of Biological Psychiatry added, "Relapse is one of the most vexing problems in depression treatment. Having a biomarker for relapse could guide a new generation of treatment research." (...)
Andre minner med p-piller?
nrk.no 22.8.2011
P-piller gir kontroll over fruktbarheten, men kan de lage krøll i minner?
Har du sett en følelsesspekket film med en venninne, men oppdager at minnene deres av den er forskjellige i ettertid? P-pille-bruk kan kanskje være forklaringen. (...)
Forskerne fra University of California, Irvine tror nå rett og slett av hormonpåvirkningen, kanskje sammen med stresshormoner som flommer når man opplever sterke følelser, kan ha innvirkning på hvordan minnene våre lagres. (...)
Forskerne hadde følgende resonnement som utgangspunkt for forskningen sin:
Studier tyder på at hukommelsen påvirkes av nivået av stresshormoner vi har i kroppen. (...)
- Ikke så overraskende
- Jeg er ikke så overrasket over at de hormonliknende stoffene i p-piller kan påvirke hukommelsen, sier Jon Storm-Mathisen.
Han er hjerneforsker og professor ved Senter for molekylærbiologi og nevrovitenskap (CMBN) og Institutt for medisinske basalfag ved Universitetet i Oslo.
- Uavhengig av om stresshormonet noradrenalin er en del av mekanismen, kan de kjønnshormonliknende stoffene som brukes i p-piller gjøre noe med virkningen av dette stresshormonet, sier han. (...)
Noradrenalin er et signalstoff som nerveceller skiller ut når vi opplever noe som påvirker følelsene, som at vi blir stressa eller redde, men også når vi opplever sterke positive følelser.
- Stoffet gjør for eksempel at en enkelt emosjonell hendelse kan bli til et varig minne, mens vi kanskje glemmer en nøytral opplevelse selv om vi kan ha hatt den mange ganger, sier Storm- Mathisen. (...)
Depressed Mothers' Offspring Have Enlarged Amygdala
medpagetoday.com 15.8.2011
MRI scans have revealed that children of depressed mothers have a larger amygdala, a part of the brain associated with emotional responses, researchers from the University of Montreal explained in the Proceedings of the National Academy of Sciences (PNAS). The authors suggest that the brains of children are sensitive to levels of child care quality. The scientists focused on the brains of ten-year-old children whose mothers had depression symptoms throughout their lives.
The authors wrote that prior studies had observed similar changes in the brains of adopted children who had been raised in orphanages - in such cases, the changes were greater. The authors believe that the key factor is personalized attention to a child's needs. (...)
Større hjerner i nord
aftenposten.no 12.8.2011
Forskere ved universitetet i Oxford
har studert menneskekranier fra
1800-tallet, og funnet at jo lenger
nordover fra ekvator kraniets innehaver
levde, jo større var hjernen.
Forskernes forklaring er vintermørket
på nordlige breddegrader, som
fordrer mer omfattende synssentra
til å hanskes med dårlige lysforhold.
Også øynene var større. Oxfordforskerne
er forbløffet over resultatene,
med tanke på at det bare er et fåtall
tusen år siden mennesket bosatte seg
i mer arktiske strøk. Resultatene er
publisert i Biological Letters. (...)
Gene Study Identifies Non-Hereditary Links to Schizophrenia
health.yahoo.net 7.8.2011
SUNDAY, Aug. 7 (HealthDay News) -- More than half the cases of non-hereditary -- or sporadic -- schizophrenia are caused by "new" protein-altering gene mutations, researchers have found.
These gene mutations, called "de novo" mutations, are new genetic errors that appear in patients but not in either of their parents, the researchers explained in the report published in the Aug. 7 online edition of the journal Nature Genetics.
In the study, the investigators examined the genomes of genetically isolated Afrikaner families of European descent in South Africa. The participants included patients with schizophrenia and their families, and healthy people in control groups.
The researchers identified 40 mutations, all in different genes and most of them protein-altering, that were associated with sporadic schizophrenia.
The findings could point the way to finding more mutations, perhaps hundreds, that contribute to schizophrenia, the study authors said. (...)
Regular Exercise Boosts the Brain, Too (Regelmessig trening gir også hjernen et løft)
health.yahoo.net 2.8.2011
TUESDAY, Aug. 2 (HealthDay News) -- Regular workouts not only do a body good, they may improve the mind as well, a new review of the data on the subject finds.
Human brains seem to benefit from regular aerobic exercise and strength training, the study found, but the researchers added that more investigation is needed to determine how exercise affects brain structure and function.
In their report, published in the online edition of the Journal of Applied Physiology, researchers led by Michelle W. Voss, of the University of Illinois at Urbana-Champaign, reviewed 111 prior studies. They found that both aerobic exercise and strength training are key to brain health and good cognition. (...)
Excess Significance Bias in the Literature on Brain Volume Abnormalities
Arch Gen Psychiatry. 2011;68(8):773-780 (August 1)
Context Many studies report volume abnormalities in diverse brain structures in patients with various mental health conditions.
Objective To evaluate whether there is evidence for an excess number of statistically significant results in studies of brain volume abnormalities that suggest the presence of bias in the literature. (...)
Conclusion There are too many studies with statistically significant results in the literature on brain volume abnormalities. This pattern suggests strong biases in the literature, with selective outcome reporting and selective analyses reporting being possible explanations. (...)
Outsmarting Sleep Loss
scientificamerican.com 30.7.2011
A tired brain struggles when faced with too many choices
Sleep deprivation affects mental performance, as anyone who has tried to work after an all-nighter can attest. Yet some professionals, including surgeons, firefighters and military personnel, must routinely work on little or no sleep. A study by researchers at the University of Texas at Austin found the sleepy brain’s Achilles’ heel—open-ended problem solving—and thus may help improve worker training in these demanding fields.
The study, which was published in Sleep in March, consisted of two types of learning tests. In the first test, sleep-deprived students were asked to categorize drawings of fictional animals as either “A” or “not A,” an open-ended task that depended on the students’ ability to remember criteria for “A” and apply it consistently. In the second test, the students sorted two types of fictional animals, “A” and “B.” The second test was more complex in that it required students to learn criteria for two animals.
The researchers suspect that attention lapses—one of the main consequences of sleep loss—are to blame. Previous studies suggest that open-ended tasks, such as the first test, require more focused attention than those that offer two clear choices, as the second test did. “When we get sleep-deprived, some of our brain’s learning systems operate better than others,” notes Todd Maddox, the study’s lead author. Fortunately, Maddox says, the more we know about the sleep-deprived brain, the better we can train people to work around its shortcomings. (...)
Pregnancy-Related Strokes on the Rise (Graviditetsrelaterte hjerneslag øker)
JAMA 2011 (July 28)
More women are experiencing strokes during pregnancy or shortly after delivery, according to a study published today in the journal Stroke.
The researchers used data from the Nationwide Inpatient Sample, the largest collection of nationwide data on hospitalizations, to compare pregnancy-related strokes in women during 2 periods: in 1994-1995 and 2006-2007. They found that although the rate of hospitalization for stroke during delivery stayed steady, the rate of hospitalization for stroke during pregnancy increased by 47% (from 0.15 to 0.22 per 1000 deliveries) and by 83% after delivery during the 12-week postpartum period (from 0.12 to 0.22 per 1000 deliveries).
Most of the increase in pregnancy-related strokes can be explained by increased rates of hypertension and heart disease among pregnant women, according to the authors. Changes in demographics, such as more women having children later in life, and improvements in medical care for women with chronic conditions, such as congential heart disease or autoimmune disorders, may explain why more women are beginning their pregnancies with cardiovascular risk factors, they note. (...)
Brain Injury: A Major Risk for Stroke (Hjerneskade. En stor risiko for hjerneslag)
Ivanhoe.com 29.7.2011
(Ivanhoe Newswire) -- Patients who suffer a traumatic brain injury have a 10-fold increased risk of having a stroke within three months, according to new research.
A traumatic brain injury happens when an external force, such as a blow or jolt to the head, disrupts the normal function of the brain. Some common causes of a traumatic brain injury include falls, car accidents and violence. About 1 in 53 Americans suffers a traumatic brain injury each year.
"It's reasonable to assume that cerebrovascular damage in the head caused by a traumatic brain injury can trigger either a hemorrhagic stroke [when a blood vessel bursts inside the brain] or an ischemic stroke [when an artery in the brain is blocked]," Herng-Ching Lin, Ph.D., senior study author and professor at the School of Health Care Administration, College of Medicine, Taipei Medical University in Taiwan, was quoted as saying. "However, until now, no research had been done showing a correlation between traumatic brain injury and stroke."
Investigators studied the risk of stroke in traumatic brain injury patients during a five-year period. During the first three months after the injury occurred, 2.91 percent of the traumatic brain injury patients suffered a stroke compared to only 0.30 percent of those without a traumatic brain injury.
The researchers say the risk of stroke gradually decreased over time. After one year, the risk was about 4.6-times greater for traumatic brain injury patients, and after five years, the risk was about 2.3-times greater. (...)
Sleep Well (Sov godt)
blogs.webmd.com 21.7.2011
Sleep disorders include a range of problems -- from insomnia to narcolepsy -- and affect millions of Americans. Dr. Michael Breus shares information and advice on sleep disorder and insomnia treatments and causes.
We are all familiar with the unpleasant effects of sleep-deprivation: fatigue, lack of energy, inattention, and irritability. Most of us should really get more sleep — it would make us feel and perform much better and can even help us lose weight. But did you know that it’s also possible to get too much sleep?
It turns out sleep is sort of like Goldilocks — you don’t want too little, and you don’t want too much.
What number is just right? The answer is really a range: somewhere between 6-8 hours. Any more or less than that may do more than just make you sleepy — it may cause your brain to age prematurely.
According to this study, both men and women who averaged seven hours of sleep performed better on reasoning tests than both people who slept fewer than six hours, as well as people who slept more than eight hours. Most interesting, the researchers involved think that the findings show that consistent sleep routines that include sleeping for around seven hours a night every night can help reduce the regular cognitive decline that happens to all of us as we get older:
• The study tracked men and women over five years and consistently asked them to perform memory, vocabulary, and logic tests.
• The study showed that people who got too little or too much sleep showed a loss in brain function that was like aging 4 to 7 years!
• People tend to sleep less when they age, so maintaining between 6-8 hours of sleep a night may be a great natural way to prevent some of that natural memory loss that occurs with aging.
You might be surprised by the fact that too much sleep could be bad for you, and you wouldn’t be alone — the researchers in the study were surprised as well. They think it may be that these people aren’t actually sleeping more than 8 hours — they may be lying in bed battling insomnia, or they may be getting poor quality sleep.
Being in bed doesn’t count — you need around seven hours of quality sleep in order to function at your best and keep your brain young. (...)
Human Brains Wired to Empathize, Study Finds (Menneskehjerner koblet for empati, ifølge studie)
health.yahoo.net 26.7.2011
TUESDAY, July 26 (HealthDay News) -- A person's brain works hard to empathize or understand what it's like to walk in other people's shoes, no matter how different they may be, a new study indicates.
Researchers from the University of Southern California found people automatically attempt to empathize -- even with those who are physically very different. To do that, however, people must use two separate regions of their brain.
In a paper, published online by Cerebral Cortex, USC researchers found that empathy between two people who can relate to each other more directly relies primarily on the intuitive, sensory-motor parts of the brain. A person who empathizes with someone who is very different or with whom they cannot directly relate, however, depends more on the rationalizing part of the brain.
In conducting the study, USC researchers showed videos of hands, feet and a mouth doing "tasks" to a woman who was born without arms or legs, as well as 13 typically developed women. The participants were also shown videos of injections being given on certain parts of the body.
As they watched the videos, the women's brains were scanned. Researchers compared those scans to pinpoint sources of empathy.
The researchers found that when the woman without limbs watched videos of tasks being performed using body parts that she did not have, the sensory-motor areas of her brain were still strongly engaged. The researchers noted, however, even without limbs, the woman was able to perform some of these tasks herself by improvising with the body parts she did have.
If the action was impossible for her however, another set of brain regions involved in deductive reasoning were also activated, the study pointed out.
The intuitive and rationalizing parts of the brain work together to create the sensation of empathy, said Lisa Aziz-Zadeh, assistant professor of USC's Division of Occupational Science and Occupational Therapy in a university news release. "People do it automatically," she said. (...)
ICAD: Exercise Protects Brain in New Studies (ICAD (International Conference on Alzheimer's Disease): Trening beskytter hjernen i nye studier)
medpagetoday.com 19.7.2011
PARIS -- Two new studies presented here add to the mountain of research indicating that physical activity in older people keeps their brains active and healthy as well.
In one, participants in the Health, Aging, and Body Composition (Health ABC) study in the highest tertile of physical activity, as measured by active energy expenditure, were dramatically less likely to develop clinical cognitive impairment than those in the lowest tertile, with an odds ratio of 0.09 (95% CI 0.01 to 0.79).
Similar findings emerged from the other study, involving participants in the Women's Antioxidant Cardiovascular Study, in which those in the higher exercise brackets had significantly lower rates of cognitive decline relative to more sedentary women. (...)
(Anm: Brains and aging. Arch Int Med 2011 (July 19).)
(Anm: Physical activity and cognition in women with vascular conditions. Arch Int Med 2011 (July 19).)
More Evidence that Exercise Is Key to Brain Health (Mer bevis på at trening er nøkkel til hjernehelse)
healthland.time.com 19.7.2011 (Time)
Regular physical activity—even walking—may be key to maintaining a sharp mind as we get older, two new studies suggest.
While that's not a new discovery, the studies plug critical gaps in the scientific literature and corroborate previous reports linking exercise to reduced rates of mental impairment in older adults.
The message is now clearer than ever: "If you stay physically active, you're buying protection for your brain," says Eric B. Larson, M.D., the vice president for research at Group Health Cooperative, a nonprofit health-care system based in Seattle. (...)
The studies appear in the July 25 print edition of the Archives of Internal Medicine and were published online today to coincide with the International Conference on Alzheimer's Disease, taking place this week in Paris.
One of the studies included 2,809 women over the age of 65 who had a history of heart disease or stroke, or at least three risk factors for those conditions. That's noteworthy because most previous studies on exercise and dementia have focused on healthy people, according to Dr. Larson, who wrote a commentary accompanying the new research.
Exercise may be particularly important for these women, since unhealthy cholesterol levels, high blood pressure, and other conditions that affect blood-vessel health have been linked to the memory and language problems known as cognitive decline, which often precedes Alzheimer's disease and other forms of dementia. (...)
More Evidence That Exercise May Keep The Brain Sharp (Mer bevis for at trening kan holde hjernen skarp)
newsday.com 19.7.2011
Even if you start late in life, physical activity can help preserve mental ability, study finds
Older adults who keep active may be helping to reduce their odds of losing their mental abilities, two new studies suggest.
Both reports were published online July 19 in the Archives of Internal Medicine, to coincide with presentations scheduled to be presented Tuesday at the International Conference on Alzheimer's Disease in Paris. (...)
Teen Binge Drinking May Alter Brain Development
JAMA 2011 (July 15)
Reduced judgment and increased participation in risky behavior are commonly seen in teenagers who binge on alcohol. Now, there is evidence suggesting that such behavior may also affect brain development and information processing, especially for teen girls, according to study findings published today in the journal Alcoholism: Clinical & Experimental Research. (...)
Et vakkert sted i hjernen
nrk.no 12.7.2011
Britiske forskere mener de har funnet et hjerneområde som gjenkjenner skjønnhet, uavhengig av medium. Det sixtinske kapell vil nok trigge dette hjerneområdet for mange.
Hjernens egen skjønnhetsflekk er funnet. Dette området lyser opp i møtet med det vakre, uansett om det befinner seg blant noter eller penselstrøk. (...)
Deltagerne klassifiserte verkene som vakre, stygge eller ingen av delene. Etterpå fikk de høre og se de samme stykkene og bildene mens forskerne fotograferte hjernene deres i en fMRI-skanner.
Bildene viste at hjernene fikk en helt spesiell reaksjon i møtet med det vakre. Både musikken og bildene økte aktiviteten i den såkalte medial orbitofrontal cortex, en del av hjernens glede- og belønningssenter.
Stygge kunst- eller musikkverk vakte derimot ikke noen lignende reaksjon i et spesielt sted av hjernen. (...)
Child's Telomeres May Tell of Early-Life Adversity (Barns telomerer kan fortelle om motgang tidlig i livet)
Psychiatr News 2011;46(13):1 (July 1) (American Psychiatric Association)
A study of institutionalized care and deprivation in childhood adds strength to the growing body of scientific literature showing a relationship between telomere length and a child's early years.
Shortening of telomeres, specialized nucleoprotein complexes located at the end of chromosomes that act as buffers and promote chromosomal stability, may be a cellular-level biomarker of early-life adversity, according to a report in the May 10 Molecular Psychiatry.
This new finding emerges from the ongoing study of a remarkable group of children who have participated in Romania's first foster-care program. (...)
“I feel really lucky to be working with this project,” said Drury. “It's an amazing study database. Seeing at the level of DNA just how these adversities can impact children shows us how much we really need to focus on and protect the caregiving relationships in every child's life.” (...)
Dette er hjerneføde
side2.no 30.6.2011
Maten som har en positiv virkning på hjernen.
Spinat og blåbær inneholder mange antioksidanter som beskytter kroppen mot angrep fra frie radikaler. Forskning viser at disse matvarene holder aldrende rotter mentalt friske, skriver for eksempel Fedon Lindberg på sine nettsider .
Han nevner også EPA i fiskeolje som gunstig for hjernen i tillegg til å redusere risikoen for depresjoner.
Helsemagasinet SHAPE har også en liste over ulike mattyper som har vist seg gunstig for ulike av hjernens funksjoner.
Rødbeter
Naturlige nitrater i rødbeter kan øke blodgjennomstrømningen til hjernen og på den måten øke hjernekapasiteten. Dette ifølge forskere ved Wake Forest University. En smakfull måte å spise rødbetene på er å riste dem og spise med en honningdressing. (...)
AIDS drugs can cause premature ageing: study (AIDS-legemidler kan forårsake for tidlig aldring, ifølge studie)
reuters.com 26.6.2011
(Reuters) - A class of generic AIDS drugs often used to treat HIV in Africa and other poor regions can cause premature aging and lead to age-related illnesses such as heart disease and dementia, scientists said on Sunday.
In a study in the journal Nature Genetics, British researchers found that the drugs, known as nucleoside analog reverse-transcriptase inhibitors, or NRTIs, damage DNA in the patient's mitochondria -- the "batteries" that power cells.
The scientists said it was unlikely that newer cocktails of AIDS drugs made by firms like Gilead, Merck, Pfizer and GlaxoSmithKline would inflict similar levels of damage, since they are thought to be less toxic to mitochondria. But more research is needed to be certain. (...)
The findings do however help explain why HIV-infected people treated with older antiretroviral AIDS drugs sometimes show advanced signs of frailty and diseases such as heart disease and dementia at an early age, the researchers said.
"DNAet i våre mitokondrier blir kopiert i løpet av vår levetid,og når vi eldes akkumuleres feil naturlig," sa Chinnery, som ledet studien. ("The DNA in our mitochondria gets copied throughout our lifetimes and, as we age, naturally accumulates errors," said Chinnery, who led the study.)
"Vi tror disse HIV-legemidler akselererer hastigheten på de feil som bygges opp. Så i løpet av for eksempel 10 år kan en persons mitokondrielle DNA ha akkumulert samme mengde feil som en person som er eldet over 20 eller 30 år." (...) ("We believe these HIV drugs accelerate the rate at which these errors build up. So over the space of, say, 10 years, a person's mitochondrial DNA may have accumulated the same amount of errors as a person who has naturally aged 20 or 30 years." )
The researchers are now looking at ways to repair or stall some of the damage caused by the drugs and say they believe that focusing on exercise -- which appears to have a beneficial effect on patients with mitochondrial diseases -- may help. (...)
(Anm: Mitochondria (mitokondrie). (mintankesmie.no).)
(Anm: aldring Kilde: Store norske leksikon.).)
Forsøg med rottehjerner kan hjælpe demente
politiken.dk 18.6.2011
Amerikanske forskere kan slå rotters hukommelse til og fra.
Gennem forsøg med rottehjerner har forskere bevist, at det er muligt at genskabe tabt hukommelse og at styrke huskeevnen over for ny information.
Det er et afgørende skridt i den forskning, som man på sigt håber kan hjælpe mennesker med demens, slagtilfælde eller andre hjerneskader, skriver The New York Times.
I en serie af eksperimenter har forskere testet, om de kunne påvirke rotternes hukommelse. Og det kunne de. (...)
Memory Implant Gives Rats Sharper Recollection
nytimes.com 19.6.2011
Scientists have designed a brain implant that restored lost memory function and strengthened recall of new information in laboratory rats — a crucial first step in the development of so-called neuroprosthetic devices to repair deficits from dementia, stroke and other brain injuries in humans. (...)
Brain, Gene Discoveries Drive New Concept of Mental Illness
Psychiatr News 2011;46(12):1 (June 17) (American Psychiatric Association)
A surprising finding from genomic research is that mental illnesses appear to be related to extremely rare but potent genetic mutations that are not associated with any specific disorder but with a variety of phenotypes categorized as mental illness.
It's time to fundamentally rethink mental illness, said National Institute of Mental Health (NIMH) Director Thomas Insel, M.D. (...)
Insel said psychiatric research today promises to produce a true science of the brain based on three core principles (see Points to Remember):
•Mental disorders are brain disorders.
•Mental disorders are developmental disorders.
•Mental disorders result from complex genetic risk plus experiential factors. (...)
What is emerging today is a picture of mental illness as the result of a pathophysiological chain from genes to cells to distributive systems within the brain, based on a patient's unique genetic variation.
One of the most surprising findings from the Human Genome Project has been that psychiatric disorders, unlike common medical illnesses, appear to be the result of extremely rare, but highly penetrant—or potent—genetic variations. And these variations are not associated with any specific illness, but with a variety of phenotypes recognized as mental disorders, Insel said. (...)
The Limits of Intelligence (Intelligensens begrensninger)
scientificamerican.com 16.6.2011
The laws of physics may well prevent the human brain from evolving into an ever more powerful thinking machine (...)
Human intelligence may be close to its evolutionary limit. Various lines of research suggest that most of the tweaks that could make us smarter would hit limits set by the laws of physics.
Brain size, for instance, helps up to a point but carries diminishing returns: brains become energy-hungry and slow. Better “wiring” across the brain also would consume energy and take up a disproportionate amount of space.
Making wires thinner would hit thermodynamic limitations similar to those that affect transistors in computer chips: communication would get noisy.
Humans, however, might still achieve higher intelligence collectively. And technology, from writing to the Internet, enables us to expand our mind outside the confines of our body. (...)
The Behavioral Immune System
scientificamerican.com 14.6.2011
How unconscious fears of infection shape many aspects of our psychology
We are prejudiced against all kinds of other people, based on superficial physical features: We react negatively to facial disfigurement; we avoid sitting next to people who are obese, or old, or in a wheelchair; we favor familiar folks over folks that are foreign. If I asked you why these prejudices exist and what one can do to eliminate them, your answer probably wouldn't involve the words "infectious disease." Perhaps it should.
What does infectious disease have to do with these prejudices? The answer lies in something that I've come to call the "behavioral immune system." The behavioral immune system is our brain's way of engaging in a kind of preventative medicine. It's a suite of psychological mechanisms designed to detect the presence of disease-causing parasites in our immediate environment, and to respond to those things in ways that help us to avoid contact with them. This has many important implications – for prejudice, for sexual attraction, for social interaction, and even for the origins of cultural differences. (And, yes, for health too.) (...)
Kreativitet länkas till psykiska sjukdomar i ny svensk studie
dagensmedicin.se 14.6.2011
Såväl bipolär sjukdom som schizofreni kopplas till kreativitet i en svensk jättestudie. För depression sågs dock inte samma samband.
Har personer som behandlats för schizofreni, bipolär sjukdom eller depression oftare än andra kreativa yrken?
Det har Simon Kyaga, läkare och doktorand vid institutionen för medicinsk epidemiologi och biostatistik vid Karolinska institutet, och medarbetare, nu tittat närmare på i en registerstudie på 300 000 patienter, deras släktingar och ett stort antal kontrollpersoner med släktingar.
Det har länge funnits en idé om att kreativitet och psykisk sjukdom har ett samband. Studier har också pekat i den riktningen, men enligt den svenska forskargruppen är det här den största populationsbaserade hittills på området. (...)
The Criminal Mind: How Drugs and Violence May Affect the Brain
healthland.time.com 10.6.2011 (Time)
Brain imaging studies of violent criminals are difficult to interpret because the most persistent among them — those who are responsible for a disproportionate amount of all crime — are not only violent but also overwhelmingly addicted to alcohol and other drugs. That makes it hard to work out which brain changes are associated with addiction (which isn't usually associated with violence) and which changes are connected with brutal behavior.
A new study aimed to tease out the differences by comparing four groups of volunteers: violent offenders who were addicted to drugs; the rare violent offenders who were not; nonviolent people with alcohol or other drug problems; and those who were neither violent nor addicted.
(More on TIME.com: An Addict's Battle With Painkiller Addiction Reveals Outdated Rehab Tactics) (...)
Fet mat kan skade hjernecellene
dn.no 10.6.2011
Personer som spiser mye fet mat kan få skadet nervecellene i hjernen som styrer kroppens vekt
De nye funnene ble denne uken presentert på en større konferanse i Boston.
- Muligheten for at hjerneskade kan være en konsekvens av overforbruk av fet mat, kan forklare hvorfor det er så vanskelig for mange overvektige personer å gå ned i vekt og holde seg der, sier professor Joshua Thaler ved University of Washington i Seattle.
Forsketeamet studert hjernen til i gnagere for å finne både kortsiktige og langsiktige effekter av et fettrikt kosthold. Dyrene gikk kraftig opp i vekt, og utviklet betennelse i hypothalamus, den delen av hjernen som inneholder nevroner som kontrollerer kroppsvekt.
Under forsøkene så forskerne at nerveceller som regulerer vekten, ble færre etter åtte måneder med fettrikt kosthold. Musene som fikk normal kost, hadde ingen endring på dette.
- Denne forskningen gir oss ny kunnskap om fedmebehandling. Hvis vi kan lage nye medisiner som begrenser nevronskade under overspising, kan det bli effektivt i kampen mot fedmeepidemien, sier professor Joshua Thaler. (...)
Studies: New Clues to the Genetic Roots of Autism
healthland.time.com 9.6.2011 (Time)
Random changes in genes, rather than changes handed down from parents, may be responsible for some cases of autism, say scientists who report in three new papers a major breakthrough in understanding where those genetic changes may lie.
The findings suggest that autism is a genetically complex disorder, involving perhaps hundreds of spontaneous changes in genes. The discoveries should help researchers gain a better understanding of the biology of the disorder and find targets for better treatments. It's latest in a steady stream of good news from autism researchers recently, who have reported on innovative ways to diagnose the disorder earlier (as we reported here, here and here) and on new genes that contribute to it (which we described here).
(More on TIME.com: Health Checkup: Kids and Mental Health) (...)
Autism's Tangled Genetics Full of Rare and Varied Mutations
scientificamerican.com 8.6.2011
Several new studies highlight the complexity of autism's genetic roots, revealing why it strikes boys more than girls and offering clues for possible new treatments (...)
Studies Probe Role of Telomere Length in Predicting, Modulating Cancer Risk
JAMA. 2011;305(22):2278-2279 (June 8)
Researchers have known for some time that telomeres, DNA-protein complexes at the ends of chromosomes, help protect the body's cells, including reducing the risk of cancer by preventing chromosomes from fusing with each other or rearranging. Emerging evidence also indicates that examining telomere length might help predict risk of certain cancers and that interventions such as stress reduction or exercise might help maintain and perhaps lengthen telomeres. (...)
“Telomeres turn out to be very important in terms of predispositions and risk of cancer . . . and there are a number of risk factors that affect telomere length,” said Scott M. Lippman, MD, of the University of Texas M. D. Anderson Cancer Center in Houston. (...)
Schrödingers katt: Telepati - Mai 2011 -...
nrk.no/nett-tv/klipp 19.5.2011
Telepati, eller tankeoverføring, blir ofte omtalt som den sjette sans. Hva sier dagens forskning om telepati? Programleder Hanne Kari Fossum følger et eksperiment hvor eneggede tvillinger tester om de er i telapatisk kontakt. (…)
Local sleep in awake rats
Nature. 2011 Apr 28;472(7344):443-7.
Abstract In an awake state, neurons in the cerebral cortex fire irregularly and electroencephalogram (EEG) recordings display low-amplitude, high-frequency fluctuations. During sleep, neurons oscillate between 'on' periods, when they fire as in an awake brain, and 'off' periods, when they stop firing altogether and the EEG displays high-amplitude slow waves. However, what happens to neuronal firing after a long period of being awake is not known. (...)
Riktig søvn best for hjernen
aftenposten.no 13.5.2011
For mye og for lite nattesøvn fører til at man blir dummere, konkluderer forskere ved University College i London i en artikkel i American Academy of Sleep Medicine. De testet en rekke kognitive evner hos forsøkspersoner delt inn etter hvor mye de sov, og fant at menn som sov mindre enn 6 og mer enn 8 timer om natten, skåret dårligere på disse testene. For kvinner var normalfeltet smalere, på omkring 7 timer. Personene som ble testet, var i sen middelalder. Undersøkelsen viser altså at det heller ikke er særlig sunt å sove for lenge. (...)
Does Your Brain Take Naps While You're Awake?
healthland.time.com 6.5.2011
Have you ever been so exhausted that you feel basically half-asleep? Turns out, that may be what's literally going on in your brain, according to a new study published in Nature.
In a study of rats, researchers found that when the animals were deprived of sleep, parts of their brains (specifically, neurons in two areas of the cerebral cortex) switched into a sleeplike state, even while the rest of the brain stayed awake — and the rats themselves appeared completely alert.
The new findings may help researchers better understand how sleep-deprivation affects human performance and may even shed light on why sleep is necessary to begin with. (...)
Brain Size, Early Growth: Clues to Autism's Causes
healthland.time.com 3.5.2011
There's been a lot of news recently about efforts to detect signs of autism in children earlier — even before age 2, which is when doctors typically make the first diagnosis based on toddlers' behavior and development. (Read about these efforts here and here.) Now a new study sheds light on another key issue — why autistic children tend to develop larger brains than those without the condition.
The brain changes in autism have been increasingly documented in studies, but the phenomenon is still largely a mystery. Does having autism make children's brains grow more quickly than those of unaffected children? Does the enlarged size precede the hallmark changes in behavior, personality and learning? And how do their brains become so big? Where is the additional volume coming from? (...)
Brain Damage Found in NFL Veteran Who Took Own Life
news.sciencemag.org 2.5.2011
Researchers this morning confirmed what former National Football League player Dave Duerson must have feared when he shot himself in the abdomen back in February, killing the 51 year old who had starred for several teams as a safety. An autopsy study showed that Duerson’s brain was riddled with classic signs of chronic traumatic encephalopathy (CTE), a form of brain damage that is becoming an increasing concern among athletes in violent contact sports. Duerson’s form of suicide was apparently carefully chosen to preserve his brain as he had texted his family that he wanted the organ to be examined at the Boston University Center for the Study of Traumatic Encephalopathy (CSTE).
At a press conference there today, researchers reported that there was evidence of moderately advanced CTE in several regions of Duerson’s brain, including the frontal cortex, amygdala, and hippocampus, which play roles in impulse control, mood, memory, and other cognitive functions. “Dave Duerson had classic pathological CTE and no sign of any other disease,” neuropathologist and CSTE Co-Director Ann McKee told the press conference. McKee notes that there’s evidence suggesting CTE predisposes people to suicide, although how remains unclear; a colleague called it a “chicken and the egg problem,” explaining that CTE may cause problems in life that encourage suicides rather than specifically promote suicidal behavior by altering the working of the brain. (...)
Ändrade sovvanor kan åldra hjärnan i förtid
sverigesradio.se 2.5.2011
Sömn är viktigt för att hålla sig pigg och alert. Och nu visar en stor brittisk studie att ändrade sömnvanor i övre medelåldern kan försämra hjärnans förmåga med motsvarande flera års åldrande.
Forskarna mätte minne, språkanvändning och andra typer av tankeverksamhet hos över 5000 personer i medelåldern. Mätningarna gjordes om fem år senare, och dom som förkortat sin sömn till mindre än sex timmar, eller förlängt den till mer än åtta timmar, presterade klart sämre än de som hade samma sovvanor som innan.
Försämringen motsvarade mellan fyra och sju års åldrande. (...)
Kartlegging av hjernens navigasjonssystemer
Tidsskr Nor Legeforen 2011; 131:654 (8.4.2011)
Hippocampus og omkringliggende områder i hjernen er viktige for hukommelse og for den kognitive representasjonen av omgivelsene rundt oss. I disse områdene er det hos rotter funnet spesialiserte celler som sender ut aksjonspotensialer når dyret er på ett bestemt sted i et miljø (plassceller). I tillegg er det identifisert retningsspesifikke celler (hoderetningsceller) og celler som aktiveres hver gang dyret passerer bestemte punkter i et rutenett som dekker omgivelsene (gitterceller). Trolig er alle disse celletypene viktige for vår evne til å navigere.
– Vi brukte mikroelektroder til å gjøre opptak av elektrofysiologiske egenskaper hos enkeltceller i hippocampus og entorhinal cortex hos unge rotter som beveget seg fritt i et definert miljø, sier forskerlinjestudent Tale Litleré Bjerknes i Trondheim, som er femteforfatter på artikkelen i Science (1). (...)
(Anm: Development of the spatial representation system in the rat. Science. 2010 Jun 18;328(5985):1576-80.)
Exposure to Pesticides in Pregnancy Can Lower Children's IQ
healthland.time.com 21.4.2011
Moms-to-be have a lot to worry about while they're expecting, especially since everything they're exposed to has a chance of affecting their developing baby.
And that includes pesticides, from the kind that farmers spray on fruit and vegetable crops to the bug-killers that we use in our homes. In three separate studies published in the journal Environmental Health Perspectives, researchers document that a mother's prenatal exposure to these chemicals can affect the cognitive development of her child, in some cases up to nine years later.
(More on TIME.com: Pregnant Women Awash in Chemicals. Is That Bad for Baby?)
In one study by Columbia University researchers, which involved African American and Dominican mothers, children born to women who had the highest levels of an organophosphate pesticide known as chlorpyrifos in the cord blood during delivery scored three points lower on IQ tests at age 7, compared with children born to mothers with the lowest levels of the pesticide. (...)
– Hjernen er vårt mest sofistikerte organ
aftenposten.no 16.4.2011
(...) Scenekunstner Robert Wilson (t.v.) har skapt en interaktiv, kunstferdig dimensjon på Teknisk Museum som lar publikum kikke inn i hjernens – både egen og andres – indre gemakker. Utstillingen er et samarbeid med Universitetet i Oslo, der rektor Ole Petter Ottersen kan konstatere at selv han, som har forsket på hjernen i en årrekke, aldri har sett hjernen fremstilt på lignende vis. (...)
Rektor og hjerneforsker Ole Petter Ottersen kjenner innsiden av hjernen bedre enn de fleste. Men han har aldri sett den fremstilt på denne måten.
– Hjernen er vårt mektigste,
mest sofistikerte
organ, og det er ikke
lett å formidle den
kompleksiteten hjernen
representerer. Denne
utstillingen har en
kaleidoskopisk arkitektur
som vekker deg med
en gang du går inn, og
benytter knep som gjør
utstillingen engasjerende
og interaktiv. Den
bruker hele registeret
av sanser, veksler hele
tiden, og gjør at du forstår
mer av hjernen også
gjennom metodene
måtene den utforskes
på, sier Ole Petter Ottersen,
rektor ved Universitetet
i Oslo. (...)
(Anm: Mind gap. Åpent for publikum fra 17. april, Teknisk Museum: Opplev den sanselig og høyst interaktive utstillingen Mind Gap! Du vil finne en spennende skog av kunnskap om hjernen. Den verdenskjente scenekunstneren Robert Wilson (USA) legger i sitt design vekt på at du selv skal bli en del av utstillingen. (uio.no 7.4.2011).)
Ecstasy use leads to brain damage (Ecstasybruk fører til hjerneskade)
hc2d.co.uk 12.4.2011
People who use the illegal drug commonly known as ecstasy (3,4-methylenedioxymethamphetamine, or MDMA) have a high risk of permanently damaging their brains, according to a recent Dutch study.
Using advanced brain scanning techniques, researchers found that regular, long-term use of ecstasy caused both memory loss and increased people's risk of Alzheimer's disease.
The study authors said they had found preliminary evidence that MDMA caused damage to the hippocampus.
They said that looking for hippocampal atrophy was a common way of diagnosing Alzheimer's disease in elderly patients.
For the study, the researchers recruited 10 men who had all taken somewhere around 250-300 ecstasy tablets over the past six-and-a-half years.
The researchers also found seven other study subjects who had not taken any ecstasy, though they had taken taken other drugs over the same period of time. (...)
Scientists find way to map brain's complexity
reuters.com 11.4.2011
(Reuters) - Scientists say they have moved a step closer to developing a computer model of the brain after finding a way to map both the connections and functions of nerve cells in the brain together for the first time.
In a study in the journal Nature on Sunday, researchers from Britain's University College London (UCL) described a technique developed in mice which enabled them to combine information about the function of neurons with details of their connections.
The study is part of an emerging area of neuroscience research known as 'connectomics'. A little like genomics, which maps our genetic make-up, connectomics aims to map the brain's connections, known as synapses. (...)
Ecstasy use leads to brain damage and loss of memory, groundbreaking research reveals
dailymail.co.uk 7.4.2011
Ecstaasy users risk damage to the brain leading to significant memory loss, a groundbreaking study has found.
The research is the first to show how long-term use of the Class-A drug causes the hippocampus, the brain’s ‘memory store’, to shrink.
Experts at the Academic Research Centre in Amsterdam scanned users’ brains to examine changes to the hippocampus. (...)
However, the study, published by part of the British Medical Journal group, was dismissed by Professor David Nutt, the Government’s former chief drugs adviser.
He claimed the research lacked enough subjects to provide ‘definitive evidence’ and called for studies with longer observation periods.
Professor Nutt was sacked in October 2009 after he said Ecstasy, LSD and cannabis were less dangerous than alcohol and cigarettes. (...)
Study: Older brains less nimble at multi-tasking
reuters.com 11.4.2011
(Reuters) - The elderly have a harder time multi-tasking than young adults because older people are far less nimble at switching neurological connections in their brains between activities, according to research released on Monday.
The findings of neuroscientists from the University of California at San Francisco add new insights to a growing body of studies showing that one's ability to move from one task to another in quick succession becomes more difficult with age.
Previous studies and anecdotal accounts of "senior moments" -- fleeting bouts of forgetfulness, especially in the midst of competing demands on attention -- have established a strong link between juggling tasks and glitches in short-term, or "working," memory, for people of all ages. (...)
2.684 år gammel syltet hjerne fundet
politiken.dk 8.4.2011
Den intakte hjerne skal hjælpe forskere forstå hjernen gennem tiden.
De har nemlig fundet en »nærmest perfekt bevaret« 2.684 år gammel hjerne i en engelsk sump. Hjernen har ligget og syltet sig selv i et iltfrit og fugtigt miljø.
Det skriver tidsskriftet Journal of Archaelogical Science Study.
Hjernen er ifølge forskerne den ældste intakte hjerne, der nogensinde er fundet i Europa og Asien. (...)
Gjør PC-en til tankeleser
itavisen.no 8.4.2011
Hjerneforskere med gjennombrudd.
Tenk på en «A». Og vips! Så kommer bokstaven A opp på skjermen.
Det høres ut som en scene fra en dårlig science fiction-film fra 1960-tallet. Men faktum er at forskerne nå klarer å få til akkurat dette.
Forstår hva vi tenker
Ved Washington University School of Medicine in St. Louis i USA har man greid å skape forbindelse mellom hjernens talesenter og datamaskinen. Foreløpig på et ganske primitivt nivå.
Men forskernes funn peker uten tvil i retning av at vi på sikt kan få PC-er som forstår hva vi tenker, og som kan gjengi det på skjermen. Eller for den saks skyld som tale gjennom høyttaleren. (...)
Beviser at kjærlighetssorg er smertefullt
aftenposten.no 5.4.2011
Kjærlighetssorg smerter like mye som en fysisk skade.
Enhver som har vært igjennom det, vet det godt. Kjærlighetssorg er vondt. Og nå er det vitenskapelig bevist av forskere ved universitetet i Michigan i Usa.
De har gjennomført en studie av 40 personer, som alle er blitt dumpet de siste seks månedene.
Testpersonene ble overvåket og monitorert, og måtte gjennom en MR scanning. Underveis ble bedt om å se på et bilde av sin tidligere kjæreste og kjenne på følelsense rundt forholdet. Deretter ble de utsatt for moderat smerte forårsaket av varme, samme temperatur som en kopp varm kaffe. (...)
Kobler antidepressiva til åreforkalkning
dagensmedisin.no 4.4.2011
Brukere av antidepressiva har mer åreforkalkning og dermed økt risiko for hjertesykdom og hjerneslag sammenlignet med ikke-brukere.
Det fremkommer av en tvillingstudie blant 500 mannlige tvillinger med en gjennomsnittsalder på 55 år. Funnene ble lagt frem på den årlige kongressen til American College of Cardiology (ACC) denne uken.
Uavhengig av depresjon
Bruk av antidepressiva førte til 5 prosent økning i tykkelsen på carotis – den store halspulsåren. Selv om tidligere forskning har vist en sammenheng mellom depresjon og økt risiko for hjertesykdom, hadde depresjon i seg selv ingen effekt på åreforkalkning (aterosklerose), skriver Reuters Health.
– Dette styrker argumentet om at det trolig er antidepressiva og ikke depresjon i seg selv som kan forklare sammenhengen med hjertesykdom, uttaler kardiolog Amit Shah, som presenterte resultatene i New Orleans.
Lavere biologisk alder
Økningen i tykkelsen på halspulsåren på grunn av antidepressiva-bruk ble beregnet å utgjøre en forskjell i biologisk alder på fire år. Med andre ord hadde tvillingen som brukte antidepressiva arterier som var fire år eldre enn brorens årer. (...)
Antidepressants linked to heart risk: twins study (Antidepressiva linket til hjerterisiko: tvillingstudie)
reuters.com 2.4.2011
(Reuters) - Middle-age men who use antidepressants are more likely to have a narrowing of blood vessels, increasing the risk of heart attacks and strokes, than those who do not use the medications, according to a study presented on Saturday.
A study of twins found evidence of atherosclerosis, as measured by the interior thickness of the carotid artery, regardless of the type of antidepressant taken. (...)
Antidepressants May Raise Risk for Cardiovascular Disease (Antidepressiva kan øke risiko for kardiovaskulær sykdom ( hjerte- og karsykdomsykdom))
depression.about.com 5.4.2011
New research suggests that antidepressants may raise the risk for cardiovascular disease.
In a study involving more than 500 middle-aged male twins, researchers found that those twins who took antidepressants of any type were more likely to have a thickening of the inner linings of the arteries in the neck than their twin brothers who didn't. This type of thickening has been previously found to be associated with heart attack and stroke.
"There is a clear association between increased intima-media [inner arterial lining] thickness and taking an antidepressant, and this trend is even stronger when we look at people who are on these medications and are more depressed," said lead investigator Dr. Amit Shah, a cardiology fellow at Emory University in Atlanta, in a written statement issued by the American College of Cardiology. "Because we didn't see an association between depression itself and a thickening of the carotid artery, it strengthens the argument that it is more likely the antidepressants than the actual depression that could be behind the association."
Dr. Shah noted that the link between heart health and antidepressants is not well-understood, but it could be that the chemical messengers that are affected by antidepressant use, such as serotonin and norepinephrine, might cause constriction of blood vessels, leading to increased blood pressure, a known risk factor for hardening of the arteries. (...)
Excess Significance Bias in the Literature on Brain Volume Abnormalities
Arch Gen Psychiatry 2011 (Published online April 4)
Context Many studies report volume abnormalities in diverse brain structures in patients with various mental health conditions.
Objective To evaluate whether there is evidence for an excess number of statistically significant results in studies of brain volume abnormalities that suggest the presence of bias in the literature.
Data Sources PubMed (articles published from January 2006 to December 2009). (...)
Linking an Anxiety-Related Personality Trait to Brain White Matter Microstructure
Arch Gen Psychiatry. 2011;68(4):369-377 (April )
Context Emotional, cognitive, and behavioral response patterns underlying temperament and personality are established early and remain stable from childhood. Anxiety-related traits are associated with psychiatric disease and represent predisposing factors for various affective disorders, including depression and anxiety. Emotional processing relies on the structural and functional integrity of distributed neuronal circuits. Therefore, anxiety-related personality traits and associated increased risk of psychiatric disease might be rooted in structural variability in large-scale neuronal networks. (...)
Conclusions Increased HA is associated with decreased WM microstructure, implying that structural connectivity modulates anxiety-related aspects of personality. Decreased WM integrity reflects increased susceptibility to psychiatric disease and represents a promising biomarker that might ultimately facilitate targeted pharmacological and psychological interventions and treatment of disease. (...)
Disruption of circadian clocks has ramifications for metabolism, brain, and behavior
PNAS 2011; 108(4):1657-1662 (Proceedings of the National Academy of Sciences)
Circadian (daily) rhythms are present in almost all plants and animals. In mammals, a brain clock located in the hypothalamic suprachiasmatic nucleus maintains synchrony between environmental light/dark cycles and physiology and behavior. Over the past 100 y, especially with the advent of electric lighting, modern society has resulted in a round-the-clock lifestyle, in which natural connections between rest/activity cycles and environmental light/dark cycles have been degraded or even broken. Instances in which rapid changes to sleep patterns are necessary, such as transmeridian air travel, demonstrate negative effects of acute circadian disruption on physiology and behavior. However, the ramifications of chronic disruption of the circadian clock for mental and physical health are not yet fully understood. (...)
Stress May Alter Gut Bacteria to Hinder Immune System (Stress kan forandre tarmbakterier og hemme immunsystemet)
drugs.com 25.3.2011
FRIDAY, March 25 -- Researchers have found that stress can alter the balance of bacteria that live in the intestine, leading to immune system problems.
Stress changes the composition, diversity and number of intestinal bacteria, said the team at Ohio State University. The communities of bacteria become less varied, and there are greater numbers of potentially harmful bacteria.
The study is published in the March issue of the journal Brain, Behavior, and Immunity. (...)
Mitochondrial Function Linked to Autism (Mitokondriell funksjon linket til autisme)
Psychiatr News 2011;46(6):1 (March 18) (American Psychiatric Association)
Treatment with antioxidants such as carnitine, coenzyme Q10, and B vitamins has been found to help some children who have both autism and mitochondrial disease.
Might mitochondria—the little packets inside cells that make energy for both brain and body—play a role in autism?
Perhaps in some cases of the disorder, two researchers believe. They are Daniel Rossignol, M.D., a primary care physician affiliated with the International Child Development Resource Center in Melbourne, Fla., and Richard Frye, M.D., Ph.D., of the University of Texas Health Science Center at Houston.
Mitochondria are best known for producing energy for the cell from oxygen and food. Because of mitochondria's role in energy production, children with mitochondrial disease have some level of dysfunction in high-energy organs such as the brain. Children with mitochondrial disease can have either normal intelligence, mental retardation, or developmental delay.
On the basis of a review of 65 studies, Rossignol and Frye concluded in a report in the January 25 Molecular Psychiatry that 1 in 20 children with autism has mitochondrial disease, which is much higher than the incidence in the general population, which is about 1 in 10,000 children. (...)
Hjernen er ikke lenger alene
uib.no 16.3.2011
Hjerneforskere og samfunnsvitere møtes til internasjonal workshop i Bergen for å bygge bro mellom hjernen og samfunnet.
Hvis det blir mulig å skanne hjernen og få kjennskap til hvordan den fungerer, vil det også ha etiske konsekvenser ved f eks diagnostisering og kanskje også i sammenheng med juridiske spørsmål.
– Det er samfunnsforskerne som sitter med en kritisk kompetanse og kan behandle de etiske spørsmålene som er knyttet til denne forskningen, sier professor Kenneth Hugdahl ved institutt for biologisk og medisinsk biologi.
Denne uken møtes stipendiater og postdoktorer på Bergen Neuroschool for å få en innføring i hjerneskanningsmetoden fMRI. Workshopen arrangeres av European Neuroscience and Society Network og fMRI-gruppen i Bergen.
– Det unike med denne workshopen her er at halvparten av stipendiatene er samfunnsvitere og den andre halvparten er hjerneforskere, sier Hugdahl. (...)
Ta en blund, lær mer
aftenposten.no 15.3.2011
En god natts søvn er viktig for å kunne lagre alt du har lært dagen før. Men det er lurt å ta seg en liten blund like før du skal lære noe nytt også, viser forskning ved University of California i Berkeley. Professor i psykologi og nevrovitenskap, Matthew Walker, lot testpersoner ta hukommelsestester på formiddagen. Resultatene ble sammenlignet med tester foretatt senere på ettermiddagen. Da fikk halvparten sove i halvannen time først, mens resten holdt seg våkne. Den våkne gruppen testet 10
prosent dårligere enn på formiddagen, mens de som hadde fått litt ekstra søvn fikk 10 prosent bedre resultater. Forskjellen mellom gruppene ble altså 20 prosent,
skriver livescience.com. (...)
Behavioral destabilization induced by the selective serotonin reuptake inhibitor fluoxetine (Destabiliserende atferd forårsaket av den selektive serotoninreopptakshemmeren (SSRI-en) fluoxetine (Prozac))
Molecular Brain 2011, 4:12 doi:10.1186/1756-6606-4-12 (16 March)
Background Selective serotonin reuptake inhibitors (SSRIs) are widely used to treat mood and anxiety disorders. However, neuronal bases for both beneficial and adverse effects of SSRIs remain poorly understood. We have recently shown that the SSRI fluoxetine can reverse the state of maturation of hippocampal granule cells in adult mice. The granule cell "dematuration" is induced in a large population of granule cells, and greatly changes functional and physiological properties of these cells. Here we show that this unique form of neuronal plasticity is correlated with a distinct change in behavior of mice. (...)
Conclusions Our results demonstrate that the SSRI fluoxetine can induce marked day-to-day changes in activity levels of mice in the familiar environment, and that the dematuration of the hippocampal granule cells is closely associated with the expression of this destabilized behavior. Based on these results, we propose that the granule cell dematuration can be a potential cellular basis underlying switching-like changes in the behavioral state associated with SSRI treatments. (...)
Depression Drugs -- SSRIs -- May Reorganize Brain Plasticity, New Research Suggests (Legemidler mot depresjon -- SSRI-er -- kan ifølge ny forskning reorganisere hjernens plastisitet)
sciencedaily.com 18.3.2011
ScienceDaily (Mar. 18, 2011) — Selective serotonin reuptake inhibitors (SSRI) such as Prozac are regularly used to treat severe anxiety and depression. They work by immediately increasing the amount of serotonin in the brain and by causing long term changes in brain function. However it can take weeks of treatment before a patient feels any effect and both beneficial effects and side effects can persist after treatment is stopped.
New research published by BioMed Central's open access journal Molecular Brain investigates physiological changes within the brain that may be caused by SSRI treatment.
The hippocampus is an area of the brain involved in long term memory and spatial awareness, and is involved in symptoms afflicting people with Alzheimer's disease, such as loss of memory and disorientation. Neuronal cells in the hippocampus can change their activity and strength of connections throughout life, a process known as plasticity, which thought to be one of the ways new memories are formed. Altered plasticity is often associated with depression and stress.
Researchers from the Department of Pharmacology, Nippon Medical School, showed that chronic treatment of adult mice with fluoxetine (Prozac) caused changes to granule cells, one of the main types of neuronal cells inside the hippocampus, and to their connections with other neuronal cells. The granule cells appeared to undergo serotonin-dependent 'dematuration', which increased their activity and reversed adult-type plasticity into an immature state. These changes to the cell's plasticity were associated with increased anxiety and in alternating between periods of hyper or hypo activity.
Katsunori Kobayashi forklarte, "Noen av sideeffektene assosiert med Prozac hos mennesker, slik som angst og endring av atferdsmønstre, kan skyldes overdreven "dematuration" av granule celler i hippocampus." (...) (Katsunori Kobayashi explained, "Some of the side effects associated with Prozac in humans, such as anxiety and behavioral switching patterns, may be due to excessive dematuration of granule cells in the hippocampus.")
Studier undersøker fysiologiske forandringer i hjernen som følge av Prozac behandling
news-medical.net 16.3.2011
Selektive serotonin reopptakshemmere (SSRI) som Prozac er regelmessig brukes til å behandle alvorlig angst og depresjon. De fungerer ved umiddelbart å øke mengden av serotonin i hjernen og ved å forårsake langsiktige endringer i hjernens funksjon. Men det kan ta uker med behandling før pasienten føler noen effekt, og både positive effekter og bivirkninger kan vedvare etter at behandlingen er stoppet. Ny forskning publisert av BioMed Central er open access tidsskrift Molecular Brain undersøker fysiologiske endringer i hjernen som kan være forårsaket av SSRI-behandling.
Hippocampus er et område av hjernen som er involvert i langsiktig hukommelse og romlig bevissthet, og er involvert i symptomene som rammer personer med Alzheimers sykdom, som for eksempel tap av hukommelse og desorientering. Nevronale celler i hippocampus kan endre sin aktivitet og styrke forbindelser gjennom hele livet, en prosess som kalles plastisitet, som antas å være en av de måtene nye minner dannes. Altered plastisitet er ofte assosiert med depresjon og stress.
Forskere fra Institutt for farmakologi, Nippon Medical School, viser at kronisk behandling av voksne mus med fluoksetin (Prozac) medfører endringer granule celler, en av de viktigste typer nevronale celler inne i hippocampus, og til sine forbindelser med andre nevronale celler. Den granule cellene så ut til å gjennomgå serotonin-avhengige 'dematuration ", som økte sin aktivitet og reversert voksen-type plastisitet i en umoden tilstand. Disse endringer i cellens plastisitet var assosiert med økt angst og i vekslende mellom perioder med hyper-eller hypo aktivitet.
Prozac reorganizes brain plasticity (Prozac reorganiserer hjernens plastisitet)
eurekalert.org 15.3.2011e
Selective serotonin reuptake inhibitors (SSRI) such as Prozac are regularly used to treat severe anxiety and depression. They work by immediately increasing the amount of serotonin in the brain and by causing long term changes in brain function. However it can take weeks of treatment before a patient feels any effect and both beneficial effects and side effects can persist after treatment is stopped. New research published by BioMed Central's open access journal Molecular Brain investigates physiological changes within the brain that may be caused by SSRI treatment.
The hippocampus is an area of the brain involved in long term memory and spatial awareness, and is involved in symptoms afflicting people with Alzheimer's disease, such as loss of memory and disorientation. Neuronal cells in the hippocampus can change their activity and strength of connections throughout life, a process known as plasticity, which thought to be one of the ways new memories are formed. Altered plasticity is often associated with depression and stress.
Researchers from the Department of Pharmacology, Nippon Medical School, showed that chronic treatment of adult mice with fluoxetine (Prozac) caused changes to granule cells, one of the main types of neuronal cells inside the hippocampus, and to their connections with other neuronal cells. The granule cells appeared to undergo serotonin-dependent 'dematuration', which increased their activity and reversed adult-type plasticity into an immature state. These changes to the cell's plasticity were associated with increased anxiety and in alternating between periods of hyper or hypo activity.
Katsunori Kobayashi explained, "Some of the side effects associated with Prozac in humans, such as anxiety and behavioral switching patterns, may be due to excessive dematuration of granule cells in the hippocampus." (...)
A New Troublesome Long-Term Effect Of Antidepressant Drugs; Tardive Dysphoria (En ny plagsom langtidseffekt av antidepressiva, tardive dysfori)
medicalnewstoday.com 8.3.2011
(...) A possible prodepressant effect of antidepressants has been previously proposed. Fava was the first to suggest that an antidepressant-related neurobiochemical mechanism of increasing vulnerability to depression might play a role in worsening the long-term outcome of the illness. Understanding of potential mechanisms of this phenomenon can be gleaned from observations regarding the short form of the serotonin transporter (5HTTR). Patients with the short form of the 5HTTR and prolonged antidepressant exposure, may be particularly vulnerable to antidepressant-related worsening. In other words, prolonged exposure to antidepressants can induce neuroplastic changes that result in the genesis of antidepressant-induced dysphoric symptoms. The investigators propose the term 'tardive dysphoria' to describe such a phenomenon and describe diagnostic criteria for it. Tapering or discontinuing the antidepressant might reverse the dysphoric state. Antidepressant discontinuation may not provide immediate relief. In fact, it is likely that transient symptoms of withdrawal will occur in the initial 2-4 weeks following antidepressant discontinuation or tapering. However, after a prolonged period of antidepressant abstinence, one may see a gradual return to the patient's baseline. (...)
Langvarig udsættelse for antidepressiva kan fremkalde tardive Dysfori
news-medical.net/news.com 9.3.2011
I den aktuelle udgave af psykoterapi og Psykosomatik en ny vigtig bivirkning af antidepressiv medicin er beskrevet: tardive dysfori.
Behandling-resistent depression (TRD) kan være relateret til utilstrækkeligt dosering af antidepressiva eller antidepressiv tolerance. Alternativt er der grund til at tro, at antidepressiv behandling selv kan bidrage til en kronisk depressiv syndrom. Denne undersøgelse rapporterer et tilfælde af antidepressiv ophør i en TRD patient, en 67-årig hvid mand med pludseligt opstået major depressiv sygdom i en alder af 45 år. (...)
Are Psychiatric Medications Causing More Mental Illness? (Forårsaker psykiatriske legemidler mer psykisk sykdom?)
radioboston.wbur.org 19.1.2011
According to some sources, the use of psychiatric drugs like ritalin, prozac and xanax, has doubled in the last decade
A local science journalist and author, Robert Whitaker, says in his recent book, “Anatomy of an Epidemic: Magic Bullets, Psychiatric Durgs, and the Astonishing Rise of Mental Illness in America,” that the long-term use of these popular psychiatric medications is actually causing more mental illness — not less.
Whitaker says his research which examines for the first time the long-term effects of psychiatric drugs, shows that these medications are often making diseases such as depression and schizophrenia worse, not better. He points to a major increase in the number of people getting federal disability benefits for mental illness who are taking these medications as a sign that the drugs are, in fact, contributing to chronic mental illness in America. For example, Whitaker points out that between 1987 and 2007, “the number of disabled mentally ill children rose thirty-five fold.”
Whitaker’s claims are refuted by reputable members of the psychiatric community here in Boston. (...)
Se den utrolige videoen!
nrk.no 4.3.2011
Sopp bryter seg inn i hjernen til maur. – Mesterlig fotografert og fantastisk utført, sier zoolog. (...)
– Dette er mesterlig fotografert og fantastisk utført, og så vakkert og skummelt som bare BBC kan gjøre det. Det er så flott at jeg nesten blir på gråten, sier zoolog Petter Bøckman til NRK.no.
Han syns ikke det er så rart at det har blitt oppdaget fire nye arter, og mener det sannsynligvis vil komme langt flere.
– Soppen må være tilpasset den hjernen den skal angripe. Forskjellige arter har forskjellige hjerner, og derved har det oppstått et ras med sopparter tilpasset de mange insektartene i tropene. Så dette er ikke overraskende, sier Bøckman. (...)
Newton: Den smarte blekkspruten
nrk.no 26.2.2011
Newton den 27. februar 2011: Blekkspruten er et av de smarteste levende vesener som fins. Den har ni hjerner, tre hjerter og åtte bein og kan forandre farge og fasong når det passer. De største blekksprutene kan bli over fem meter lange. Originaltittel: Aliens of the Deep Seas, copyright: Zed. Kommentar: Torfinn Borkhus. (...)
Hjärnan luras på en tredje arm
dn.se 24.2.2011
DN:s reporter Anna Bratt får uppleva illusionen av att ha tre armar. När försöksledaren Arvid Guterstam låtsas skära ett snitt i extrahanden upplever hon att hennes egen hand är hotad.
Forskare på Karolinska institutet har fått människor att bli trearmade – åtminstone enligt sin egen upplevelse. Resultaten kan komma att användas till hjälp för handikappade. (...)
Meditasjon endrer hjernen
aftenposten.no 18.2.2011
Man vet at munker som har meditert mer
enn 10 000 timer, har hjerner som ser annerledes
ut. nå viser en studie utført ved
Harvard Medical school at det er nok å
meditere i to måneder for at hjernen skal
begynne å endre struktur. Det skjer i hippocampus,
som vokser i størrelse og gjennomgår
en fortetning. Hippocampus er sentral
for minner, emosjoner og sanseopplevelser.
Undersøkelsen, som er publisert i psychiatry
Research, viser hvordan antall nerveceller
øker og antall synapser stiger. synapsene
er forbindelser mellom hjerneceller, og
en økning i antall skulle vitne om forbedret
tenkeevne. Det som forundrer, er at denne
økningen i kompleksitet skjer så raskt. (...)
Datamaskin ble Jeopardy-mester
nrk.no 17.2.2011
USAs to beste Jeopardy-deltagere hadde ingenting å stille opp med mot superdatamaskina Watson.
At datamaskiner har større kapasitet enn mennesker på en god del områder er det nok få som betviler. Men at de skal være i stand til å overvinne mennesker i spørrekonkurranser på de tobeintes premisser, er nok hakket mer oppsiktsvekkende.
IBMs superdatamaskin Watson hadde likevel små problemer med å slå USAs to beste deltagere i det ikoniske spørreprogrammet Jeopardy. (...)
Immune imbalance in gut may trigger celiac disease
reuters.com 9.2.2011
(Reuters) - People who have high levels of an immune system compound called Interleukin-15 may be primed to develop celiac disease, a digestive disorder that keeps sufferers from eating foods like cereal, pasta, cookies and beer.
Blocking this compound in mice helped reverse the disease, U.S. researchers said on Wednesday.
Vitamin A and retinoic acid, a byproduct of vitamin A used in the acne treatments Retin-A and Roche's former acne drug Accutane, may exacerbate the problem, acting as a trigger for the inflammatory response, the team said.
The findings, published in the journal Nature, suggest that an imbalance of compounds like Interleukin 15 that regulate the immune system could be an underlying cause of food allergies. (...)
Færre feil med svekket hjerne
nrk.no 8.2.2011
Når et område av hjernen blir satt ut av spill, tar andre områder over, slik at vi faktisk begår færre feil.
Vi gjør færre feil når en del av hjernen er slått av.
Det lyder som et paradoks, men ikke desto mindre er det konklusjonen på et forsøk på Hvidovre Hospital i Danmark.
Les: – Fremmede bakterier styrer hjernen (...)
Å forklare psykisk sykdom
Tidsskr Nor Legeforen 2011; 131:254-6 (4.2.2011)
Hva vil det si å forklare psykiske lidelser? Hvordan er bakgrunnsfaktorene ved disse lidelsene relatert til hverandre? En multinivåforklaringsmodell synes å kunne gi svar på spørsmålene.
Det er neppe noen som er uenig i at både biologiske, psykologiske og sosiale faktorer må tas med når vi skal forklare psykiske lidelser. Selv om dette synspunktet kan virke trivielt, er det likevel to problemer som melder seg i denne forbindelse. For det første: Hvordan er disse faktorene integrert med hverandre? For det annet: Hva vil det si å forklare psykiske lidelser?
Det vil bli argumentert for at disse to relaterte problemene best kan løses innenfor rammen av en vitenskapsfilosofisk modell som er svært innflytelsesrik innenfor biologiens filosofi (1, 2). Den kalles en «multinivåforklaringsmodell» (også «mekanistisk forklaringsmodell»). De to nevnte problemene er nær knyttet til ulike teorier om reduksjonisme, og jeg vil derfor først redegjøre for hva som menes med dette begrepet. Deretter vil jeg gi en fremstilling av multiforklaringsmodellen og noen av dens viktigste implikasjoner. (...)
Arvesynden. Kan være både arv og miljø
aftenposten.no 1.2.2011
Harald Eia skapte rabalder med sitt spørsmål «født sånn eller blitt sånn?». Ny forskning tyder på at svaret kan være «ja takk, begge deler» – at livsførsel kan gå i arv og påvirke både barn og barnebarn. (...)
Genene kan slåes av og på. Vi har 20.000-25.000 gener, som tilsammen utgjør den lange DNA-strengen. (...)
- Vekta sitter i hjernen
nrk.no 31.1.2011
Skal du gjøre noe med vekta, må du omprogrammere hjernen, mener Martin Ingvar.
Lær deg å belønne hjernen riktig, så går du ned i vekt for godt. Det mener den svenske hjerneforskeren Martin Ingvar. Her er huskelappen som får deg ned i vekt!
Hvor mange ganger har du gått ned noen kilo, følt deg fin - og så gått opp igjen de samme kiloene og vel så det?
- Vi spiser mat som gjør at vi spiser for mye, sier Martin Ingvar til NRK Puls.
Han forsker på belønningssystemet i hjernen, og har sammen med journalist Gunilla Eldh gitt ut bøkene «Hjärnkoll på maten» og «Hjärnkoll på vikten». Sistnevnte er nylig utgitt på norsk.
Automatisk overspising
Det handler om å stimulere hjernen riktig, slik at du ikke får lyst til å spise mer enn du trenger.
- Begynner du dagen med en «sukkerfrokost», blir du sulten igjen allerede klokka ti. Da tar du kanskje en bolle, som igjen gjør at du spiser mer til lunsj, eksemplifiserer Ingvar.
Så vil du igjen føle behov for en sjokolade i løpet av ettermiddagen, spise mer til middag og få lyst på noe godt på kvelden.
- Hvis du prøver å gå ned i vekt uten å endre på hva du spiser, vil du tenke på mat dag og natt. Og når du har slanket deg ferdig, vil du gå opp igjen, konstaterer han. (...)
Exercise, Brain Volume Linked in Older Adults (Link mellom trening og hjernevolum hos eldre voksne)
medpagetoday.com 31.1.2011
(...) In a randomized trial involving men and women in their mid-60s, walking three times a week for a year led to increases in the volume of the hippocampus, which plays an important role in memory, according to Arthur Kramer, PhD, of the University of Illinois Urbana-Champaign in Urbana, Ill., and colleagues. (...)
Alle gikk ned to buksestørrelser på fire uker
nrk.no 31.1.2011
Edward Grönroos, Hege Limbodal og Stein Viggo Sagvolden har ingen problemer med å løfte Yngvar Andersen etter at han har bestemt treningen deres de siste fire ukene.
De tre slappfiskene som forandret livsstil med vårt treningsprogram, gikk til sammen ned 27 centimeter rundt magen i januar. Sjekk hvem som gikk ned mest, og hvordan du kan klare det samme. (...)
Mini-Strokes Leave 'Hidden' Brain Damage (Minislag (TIA; drypp) gir "skjult" hjerneskade)
sciencedaily.com 27.1.2011
ScienceDaily (Jan. 27, 2011) — Each year, approximately 150,000 Canadians have a transient ischemic attack (TIA), sometimes known as a mini-stroke. New research published January 28 in Stroke, the journal of the American Heart Association shows these attacks may not be transient at all. They in fact create lasting damage to the brain.
The stroke research team, led by Dr. Lara Boyd, physical therapist and neuroscientist with the Brain Research Centre at Vancouver Coastal Health and the University of British Columbia, studied 13 patients from the Stroke Prevention Clinic at Vancouver General Hospital and compared them against 13 healthy study participants. The TIA subjects had all experienced an acute episode affecting motor systems, but had symptoms resolved within 24 hours. The patients were studied within 14-30 days of their episode, and showed no impairment through clinical evaluation or standard imaging (CT or MRI). Participants then underwent a unique brain mapping procedure using transcranial magnetic stimulation (TMS) with profound results.
"What we found has never been seen before," says Dr. Boyd, who also holds the Canada Research Chair in Neurobiology of Motor Learning at UBC. "The brain mapping capabilities of the TMS showed us that TIA is actually causing damage to the brain that lasts much longer than we previously thought it did. In fact, we are not sure if the brain ever recovers." (...)
(Anm: TIA - "drypp" (...) Plutselig mister du noe av følelsen i høyre arm og ben. Du må støtte deg mot et tre for ikke å falle. (nhi.no).)
(Anm: Hjerneslag (apopleksi) er plutselig innsettende tap av kroppsfunksjoner på grunn av forstyrrelser i hjernens blodsirkulasjon. Hjerneblødning er årsak i 10-15% av tilfellene, mens blodpropp i blodårer i hjernen (trombose) er årsaken i 80-85% av tilfellene. Går symptomene tilbake i løpet av 24 timer, kaller vi det transitorisk iskemisk atakk, TIA - på norsk brukes betegnelsen "drypp". De fleste TIA varer i under en time. (nhi.no).)
(Anm: apopleksi, apoplexia cerebri, hjerneslag, akutte fokale nevrologiske symptomer og utfall som varer i mer enn 24 timer og som skyldes skade av hjernevev enten på grunn av regionalt redusert blodsirkulasjon (hjerneinfarkt) eller på grunn av hjerneblødning. Kilde: Store norske leksikon.)
TIA Doubles Risk for Later Heart Attack (TIA dobler risiko for hjerteinfarkt)
medpagetoday.com 24.3.2011
The occurrence of a transient ischemic attack (TIA) doubles a person's risk for a subsequent myocardial infarction, a population-based study found.
The relative risk for myocardial infarction (MI) among a cohort of patients who had experienced a prior TIA was 2.09 (95% CI 1.52 to 2.81), according to Robert D. Brown Jr., MD, and colleagues from the Mayo Clinic in Rochester, Minn.
The risk was highest for patients whose TIA occurred before age 60 (RR 15.1, 95% CI 4.11 to 38.6), the researchers reported online in Stroke: Journal of the American Heart Association. (...)
Psychopaths' Lack of Empathy Mimics Brain Injury: Research (Psykopaters manglende emapti mimikerer hjerneskade, ifølge forskning)
health.msn.com 28.1.2011
Treatment for frontal lobe damage may also help those with personality disorder
FRIDAY, Jan. 28 (HealthDay News) -- People who have suffered a frontal brain injury have been known to have difficulty showing empathy, and new research shows that people diagnosed as psychopathic also have the same emotional deficiency.
The finding suggests that psychopaths may benefit from therapy similar to that used to treat frontal brain injury patients, said the researchers at the University of Haifa in Israel.
Psychopathy is a personality disorder characterized by extreme anti-social behavior and intention to harm others. Empathy is the ability to identify and understand another person's feelings and thoughts. (...)
Hjerneforandringer gir fødselskomplikasjoner
dagensmedisin.no 25.1.2011
Endringer i bestemte hjernestrukturer henger sammen med svangerskaps- og fødselskomplikasjoner.
Lege og forsker Unn Kristin Haukvik kom frem til dette da hun gjennom sitt doktorgradsarbeid forsøkte å finne ulikheter mellom hjernestrukturer hos personer med schizofreni og friske. (...)
Hukommelsesområde
Haukvik fant også en relasjon mellom volum av hippocampus (et område involvert i hukommelse) og alvorlige svangerskaps- og fødselskomplikasjoner hos både pasientene og hos de friske. Denne sammenhengen så ut til å bli påvirket av en genetisk variasjon i et gen involvert i glutamatmetabolismen (et signalstoff i hjernen). (...)
Neuroleptic malignant syndrome: a neuroimmunologic hypothesis
CMAJ 2010;182 E834-E838 (December)
Her er hjernen til verdens mest fryktløse kvinne
nrk.no 17.12.2010
(...) Forskere har gjort alt de kan for å skremme en kvinne som mangler det sentrale fryktsenteret i hjernen.
Den 44 år gamle kvinnen er verken redd for å kose med giftige slanger, fugleedderkopper eller møte mordere og spøkelser i mørke kjellere.
Det er amerikanske forskere fra universitetet i Iowa som har funnet fram til den fryktløse 44 år gamle kvinnen.
Forskningen ble offentliggjort i tidsskriftet Current Biology torsdag, skriver Experimentarium.dk. (...)
Oppsiktsvekkende
Kvinnen har en meget sjelden hjerneskade, hvor det sentrale fryktsenteret i hjernen har mistet sin funksjon.
Resultatene er så oppsiktsvekkende at selv den garvede fryktforskeren blir overrasket.
– Historien bekrefter våre mistanker om at amygdala er det sentrale fryktsenteret i hjernen, sier Poul Videbech.
Det er for eksempel amygdala som får oss til å trekke beina hurtig til oss hvis vi ser en slange i gresset. (...)
Infidelity Might Be in the Genes (Utroskap kan være i genene)
businessweek.com 3.12.2010
Study found dopamine receptor variant plays major role in sexual behavior
FRIDAY, Dec. 3 (HealthDay News) -- Genetics might help explain why some people are more prone to infidelity and promiscuity, says a new study.
Researchers analyzed the DNA of 181 young adults who provided a complete history of their sexual activity and intimate partnerships. They concluded that the dopamine receptor D4 (DRD4) gene plays a major role in sexual behavior.
Previous research has linked the DRD4 gene, which influences brain chemistry, to sensation-seeking activities such as gambling and alcohol use. (...)
Bruker reseptbelagte og illegale midler
aftenposten.no 24.11.2010
Norske studenter doper seg for å gjøre det bedre på eksamen, viser ny undersøkelse.
Eksamenstiden er for mange stressende med sitt fokus på pensum, lesing, prestasjoner og karakterer, og noen tyr til uheldige virkemidler for å komme seg igjennom denne tiden.
I Norge oppgir nemlig omtrent 3 prosent av studentene at de har tatt enten reseptbelagte eller illegale legemidler for å prestere bedre på eksamen, melder studentavisen Universitas.
Det viser en undersøkelse Sentio har gjennomført på vegne av Universitas og Norsk Studentorganisasjon (NSO). (...)
Etisk Råd: Pas på ny doping
berlingske.dk 29.11.2010
Det er forkert, at raske tager medicin for at koncentrere sig, mener Etisk Råd.
Etisk Råd forudser så store fremtidige problemer med hjernedoping, at rådet nu opfordrer universiteter og virksomheder til at udarbejde en politik på området. Læger har længe advaret mod hjernedoping, hvor raske studerende tager eksempelvis ADHD-medicin for at øge koncentrationen i forbindelse med studier og især op til eksamen. (...)
»I vores samfund er vi en del af fællesskabet, uanset om vi er perfekte eller uperfekte. Hvis det uperfekte kan kureres med medicin, så kan man frygte, at det vil gå ud over tolerancen i samfundet, og at det bliver illegalt at være ked af det eller genert - man kan jo bare tage en pille.« (...)
Danskere modellerer hjernens fæstningværk
berlingske.dk 26.11.2010
Blod-hjerne-barrieren beskytter vores hjerner mod fremmede stoffer. Dansk forskning kan føre til bedre medicin mod f.eks. Parkinsons, Alzheimers og depression.
Kroppen passer godt på vores vigtigste organ. Hjernen sidder velbeskyttet mod slag og stød i kraniekassen, ophængt i sin egen væskestøddæmper. Inde hjernen ligger desuden i hver eneste lille blodåre et enestående fysisk og kemisk forsvarsværk, som forhindrer fremmede stoffer fra blodet i at trænge ind i hjernen.
»Den fantastiske blod-hjerne-barriere beskytter ikke kun mod giftstoffer udefra, men også mod naturlige forhold i kroppen. Hjernen kan for eksempel ikke tåle udsving i saltbalancen, så barrieren sørger for en konstant saltkoncentration i hjernen, selv om den svinger i blodet,« siger ph.d.-studerende ved Det Farmaceutiske Fakultet, Københavns Universitet, Hans Christian Helms. (...)
Mer effektiv med kaffe og druesukker
forskning.no 25.11.2010
Bilder av hjernen avslører at en kombinasjon av kaffe og druesukker kan gjøre deg mer effektiv.
Spanske forskere har funnet ut at koffein og druesukker ser ut til å forsterke hverandres effekt, og at kombinasjonen av de to stoffene kan øke hjerneaktiviteten.
- Hovedfunnet vårt er at kombinasjonen av de to stoffene forbedrer kognitiv prestasjon ved å holde i gang konsentrasjonen og hukommelsen.
- Stoffene forbedrer effektiviteten i de to områdene i hjernen som tar seg av disse tingene, sier Josep M. Serra-Grabulosa, som ledet studien, i en pressemelding fra Universitat de Barcelona.
Studien er publisert i det siste nummeret av tidsskriftet Human Psychopharmacology: Clinical and Experimental. (...)
Scientists May Have Solved an HIV Mystery (Forskere kan ha løst HIV-mysterie)
business.dk 24.11.2010
Mechanism for death of critical immune cells identified in study
WEDNESDAY, Nov. 24 (HealthDay News) -- Scientists believe they've discovered how HIV triggers the death of the immune system's defensive CD4 T cells, which in turn leads to AIDS.
It was believed that most immune cells that die in people with HIV are not actually infected, a situation labeled "bystander cell killing." In the new study, the researchers found that these "bystander" cells die because of a failed or abortive HIV infection.
"Our study reveals that the virus actually enters CD4 T cells that are destined to die and that the virus starts to make a DNA copy of its RNA, a process called reverse transcription," lead author Gilad Doitsh at the Gladstone Institute of Virology and Immunology in San Francisco, said in an institute news release. (...)
Sabrilex og unormale funn ved MR-undersøkelser
legemiddelverket.no 19.11.2010
Det er rapportert tilfeller av unormale funn ved MR-undersøkelse av hjernen, spesielt hos spedbarn behandlet med høye doser Sabrilex (vigabatrin). I enkelte tilfeller er det også sette bevegelsesforstyrrelser i forbindelse med disse unormale MR-funnene. Det er ikke rapportert tilfeller i Norge.
Sabrilex (vigabatrin) brukes i kombinasjonsbehandling ved visse typer epilepsi samt i behandling av infantile spasmer (West syndrom). Det er rapportert om tilfeller av unormale funn ved MR-undersøkelser hos spedbarn med infantile spasmer som har vært behandlet med høye doser vigabatrin. Endringene er sett i grå substans i en liten subgruppe pasienter under 3 år. Generelt har endringene vært forbigående og blitt borte når behandlingen avsluttes. I enkelte tilfeller er det også meldt om forbigående bevegelsesforstyrrelser, slik som dystoni, dyskinesi og/eller hypertoni i tilknytning til MR-endringene. Eventuell sammenheng mellom bruk av vigabatrin, MR-endringer og bevegelsesforstyrrelsene er uklar. (...)
Scientists Get A Better Look At The Brain
blogs.forbes.com 17.11.2010
Sections of neurons captured with new imaging technology from Stanford researchers.
While large pharmaceutical companies like Pfizer, Eli Lilly and Bristol-Myers Squibb spend millions of dollars pursuing new treatments for neurological diseases like Alzheimer’s, a huge impediment to their success lies in the fact that the brain and diseases affecting it are still not well understood. As my colleague Bob Langreth has pointed out several times, including here, there is still quite a bit of controversy about what causes Alzheimer’s. (...)
Taranteller avdekker hjernens fryktmekanismar
nrk.no 10.11.2010
Engelske forskarar har funne ut hjernen din reagerer ulikt avhengig av om du ser ein tarantell nærme seg eller fjerne seg. (...)
I ein studie som er publisert i PNAS (Proceedings of the National Academy of Sciences of the United States of America) , har Dean Mobbs og hans kollegaer brukt funksjonell MRI til å sjå hjernens respons på frykt for taranteller hos 20 frivillige forsøkspersonane. (...)
Blant områda som lyste opp i hjernen til forsøkspersonane var eit område kalla det peri-aquaduktale grå, det mandelforma amygdala, og ein kjerne i stria terminalis.
Amygdala er frå før kjent for å spele ei nøkkelrolle i behandling og hukommelse av kjenslemessige reaksjonar, som til dømes frykt. (...)
Manic episodes are associated with grey matter volume reduction — a voxel-based morphometry brain analysis
Acta Psychiatrica Scandinavica 2010; 122(6): 507–515 (December)
Manic episodes are associated with grey matter volume reduction — a voxel-based morphometry brain analysis.
Objective: To investigate whether the lifetime number of affective episodes or illness duration is associated with changes in local grey matter volume, in patients with bipolar I disorder without comorbid conditions. (...)
Conclusion: We found strong evidence for a linear correlation between a decrease in DLPFC volume and the lifetime number of manic episodes in patients with bipolar I disorder. Interestingly, DLPFC is known to be important for executive functions and the findings in this study might hence be linked to the executive cognitive deficits associated with bipolar disorder. (...)
(Anm: Grey (often spelled gray in the United States, see spelling differences) describes the colors ranging from black to white. (en.wikipedia.org).)
Menneskets tankar lest av forskarar
nrk.no 30.10.2010
I eit eksperiment gjort av amerikanske forskarar klarte forsøkspersonar berre ved tankekraft å bestemme kva som skulle visast på ein skjerm.
Dette var mogleg fordi forskarane hadde "logga seg på hjernen" til forsøkspersonane og fanga opp signala frå nervecellene.
–Det er ikkje første gong vi har klart å "lese" menneskets tankar, men det er første gong det har blitt gjort på denne måten, seier professor Jon Storm-Mathisen ved Senter for molekylærbiologi og nevrovitskap ved Universitetet i Oslo til NRK.no.
–Verkeleg "tankelesing" er meir komplekse saker, legg Storm-Mathisen til. (...)
Studien som er publisert i tidsskriftet Nature viste at forsøkspersonane klarte å få fram ønska bilete i meir enn 2 av 3 forsøk, og dei lærte raskt korleis dei skulle få dette til. (...)
Aetiology and management of depression
The British Journal of Psychiatry (2010) 197: A19
(...) Goodyer and colleagues (pp. 365–371) provide evidence that the onset of depressive illness in adolescents could be predicted by the effects of two gene variants on cortisol levels. They suggest that these gene variants provide valuable additional information which could contribute to salivary cortisol becoming a useful biomarker for depression in adolescence. An accompanying editorial by Duffy (pp. 341–342) places these findings in a wider context and examines the journey from predisposition to developing the illness. She concludes that the single most useful predictive factor for developing mood disorder is a positive family history, but that studies of genetic and epigenetic factors will offer the opportunity to identify those at greatest risk of developing illness, and thus contribute to understanding intermediate causal mechanisms. Pasco et al (pp. 372–377) identify serum levels of C-reactive protein as an independent risk marker for major depressive illness in women, supporting the role of inflammatory activity in the pathophysiology of depression. They also suggest that this could provide a link with commonly comorbid medical disorders, explaining the increased risk of depression in physical illness, and question whether this could offer scope for prevention. (...)
Immune system may help cancer cells hide out: study
reuters.com 28.10.2010
(Reuters) - Cancer cells may find a hideout in the body's immune system, researchers said on Thursday in a study that may help explain why tumors can come back after rounds of toxic chemotherapy.
Tests on mice showed that the stress of chemotherapy drives some tumor cells into the thymus, the gland that produces immune cells known as T-cells.
The gland bathes these rogue tumor cells with protective agents, the researchers at the Massachusetts Institute of Technology reported in the journal Cell. The findings suggest that cancer treatments need to attack this hiding place.
"Successful cancer therapy needs to involve a component that kills tumor cells as well as a component that blocks pro-survival signals," MIT's Michael Hemann said in a statement.
"Current cancer therapies fail to target this survival response." (...)
- Forelskelse er som kokain
nrk.no 26.10.2010
Vi forelsker oss på et femtedels sekund, og rusen er som kokain. Det er blant konklusjonene i en ny studie. (...)
Tolv ulike deler av hjernen er aktive når vi forelsker oss, ifølge en stor gjennomgang av studier på området, ledet av assisterende professor Stephanie Ortigue ved Syracuse University i USA. (...)
Forelskelsen kan i stor grad knyttes til belønningssenteret i hjernen. (...)
Fatigue after traumatic brain injury: Association with neuroendocrine, sleep, depression and other factors.
Brain Inj. 2010;24(12):1379-88.
Objective: Define associations between post-traumatic brain injury (TBI) fatigue and abnormalities in neuroendocrine axes, sleep, mood, cognition and physical functioning. (...)
Conclusions: Robust correlates of fatigue were gender, depression, pain and memory and motor dysfunction. Investigation of post-TBI fatigue should include screening for depression, pain and sleep disturbance. There was no correlation between pituitary dysfunction and fatigue; however, the relatively high prevalence of hypothyroidism and adrenal dysfunction suggests screening for these hormone deficiencies. (...)
Promenader räddar din hjärna
dn.no 16.10.2010
Promenera mera, så förhindrar du att din hjärna krymper. Det i sin tur minskar risken för demenssjukdomar när du blir äldre. Det hävdar amerikanska forskare i en ny studie.
I studien, som publiceras i tidskriften Neurology, granskades 299 vuxna personer med en genomsnittsålder på 78 år.
Walking Correlates With Brain Volume, Cognitive Ability (Gåing korrelerer med hjernevolum, kognitive evner)
medpagetoday.com 14.10.2010
Seniors committed to walking had larger gray-matter volume and less cognitive impairment years later than those with more sedentary habits, researchers said. (Seniorer som holder seg i form ved gåig hadde større grå substansvolum og mindre kognitiv svekkelse år senere enn de med mer inaktive vaner, ifølge forskerne)
Among 299 cognitively normal participants in the large Cardiovascular Health Study, those in the top quartile of distance walked each week at baseline had markedly higher gray-matter volumes when measured by MRI nine years later compared with participants in the lower three quartiles, according to Kirk Erickson, PhD, of the University of Pittsburgh, and colleagues. (...)
(Anm: grå substans; betegnelse på de områdene av hjernen og ryggmargen som hovedsakelig består av nerveceller, i motsetning til de hvite partiene, som består av nervetråd ... Kilde: Store norske leksikon.)
Forskere finder forbindelse mellem gulsot og autisme
politiken.dk 11.10.2010
Årstiden for fødslen kan spille ind på risikoen for gulsot. (...)
Det har danske forskere påvist i en ny undersøgelse, der ifølge Skejby Sygehus netop er offentliggjort i det anerkendte amerikanske tidsskrift 'Pediatrics' . (...)
Danish Study Suggests Jaundice-Autism Link (Dansk studie antyder link mellom gulsott og autisme)
health.msn.com 11.10.2010
But other experts say finding is very preliminary and call for additional research
MONDAY, Oct. 11 (HealthDay News) -- Newborn babies who have jaundice may be at higher risk of developing autism later on, new research suggests, but other experts said far more research needs to be done before a cause-and-effect relationship is proven.
Researchers in Denmark analyzed information from national registries that included all Danish children born between 1994 and 2004, nearly 734,000 children.
Babies who developed serious jaundice in the days after birth were 67 percent more likely to be diagnosed with autism later on. Babies with jaundice were also more likely to develop other types of "psychological development" delays, according to the study. (...)
Därför blir MS allvarligt för vissa
sverigesradio.se 28.9.2010
Brist på ett enzym i immunförsvaret kan göra att sjukdomar som MS, multipel skleros, förvärras. Det har forskare vid Göteborgs universitet upptäckt. Den här kunskapen kan på sikt leda till nya behandlingsmetoder av MS kanske även ett vaccin, tror forskarna. (...)
Risk för tandlossning hos feta barn
sverigesradio.se 27.9.2010
Ungdomar med fetma kan drabbas av tidig tandlossning. Det slår forskare fast efter en pilotstudie som visar att påfallande många ungdomar med fetma har djupa tandfickor.
Dessa beror inte på dålig tandhygien på grund av till exempel dålig tandborstning utan på att fetma i sig ökar inflammationen i kroppsvävnader, även munnen. Det säger Thomas Modéer, professor i barntandvård vid institutionen för odontologi vid Karolinska institutet.
– Vi påvisar ett samband mellan fetma och riskfaktorer för tandlossningsjukdomen hos tonåringar. I förlängningen kan det leda till en tandlossningssjukdom och så småningom en tandförlust, säger Thomas Modéer. (...)
- Multi-tasking er en myte
dn.no 22.9.2010
Multi-tasking - å klare flere oppgaver samtidig - er en myte.
- Det tilsvarer å være småfull, sier den danske hjerneforskeren Kjeld Fredens til politiken.dk.
Skal velferdssamfunnet overleve, må vi ikke bare jobbe raskere, vi må konsentrere oss også, ifølge forskeren. (...)
Ifølge Kjeld Fredens vil evnen til å multitaske være utviklet hos oss om 200 år, fordi utviklingen vil gå i retning av at multitaskerne har formert sig, og de som bare klarer en ting av gangen er døde av stress. (...)
Telomeres Tell Future in Aplastic Anemia
medpagetoday.com 21.9.2010
Shortened telomeres in peripheral blood leukocytes may predict relapse, malignant progression, and poorer survival in patients with severe aplastic anemia, researchers at the National Institutes of Health (NIH) reported.
An analysis of average pretreatment telomere length in almost 200 patients with severe aplastic anemia treated at the NIH, revealed that patients in the first quartile for telomere length -- the shortest telomeres -- had an overall six-year survival rate of 66% (95% CI 52.9% to 82.5%) compared with 83.8% (95% CI 77.3% to 90.0%) among those in the other three quartiles (P=0.008), according to the Sept. 22 issue of the Journal of the American Medical Association. (...)
Brain's default mode network may hold key to better psychiatric diagnoses
latimes.com 30.8.2010
Malfunctioning brain activity can be differentiated in people with depression, autism, schizophrenia and PTSD, studies show.
A series of studies published in recent years suggests that in people with depression, autism, schizophrenia and post-traumatic stress disorder, the default mode network, that curious pattern of brain activity that ramps up when we daydream, works differently than it does in healthy control subjects.
And in each condition, the malfunctions look slightly different, holding out the prospect of better psychiatric diagnoses down the line. (...)
YOUR BRAIN ON COMPUTERS
Digital Devices Deprive Brain of Needed Downtime
nytimes.com 24.8.2010
(...) The technology makes the tiniest windows of time entertaining, and potentially productive. But scientists point to an unanticipated side effect: when people keep their brains busy with digital input, they are forfeiting downtime that could allow them to better learn and remember information, or come up with new ideas. (...)
Trente hjernen yngre
aftenposten.no 21.8.2010
Norske forskere har funnet fysisk bevis på at hukommelsestrening faktisk holder gamle hjerner i form: Hjernebarken blir tykkere.
At det er sammenheng mellom mental aktivitet og risikoen for demens, er påvist i flere studier. Men hva «trimmen» faktisk fører til i aldrende hjerner, har vært ukjent.
Det vi vet, er at den ytterste delen av hjernen, hjernebarken, blir tynnere med alderen. Tynningen er særlig uttalt ved demenssykdommer, mens en tykk hjernebark er positivt for hukommelsen hos eldre. Nå har forskere ved Universitetet i Oslo funnet at uttynningen i hjernen ikke bare kan bremses, men også snus ved aktiv trening. (...)
Determinants of disparities between perceived and physiological risk of falling among elderly people: cohort study
BMJ 2010;341:c4165 (19 August)
Objectives To gain an understanding of elderly people’s fear of falling by exploring the prevalence and determinants of perceived and physiological fall risk and to understand the role of disparities in perceived and physiological risk in the cause of falls. (...)
Conclusion Many elderly people underestimated or overestimated their risk of falling. Such disparities between perceived and physiological fall risk were primarily associated with psychological measures and strongly influenced the probability of falling. Measures of both physiological and perceived fall risk should be included in fall risk assessments to allow tailoring of interventions for preventing falls in elderly people. (...)
Bad bumps to head could kill years later: U.S. study (Voldsomme slag til hodet kan ifølge amerikansk studie være dødelig flere år senere)
reuters.com 17.8.2010
(Reuters) - Scientists reported on Tuesday they have some of the best evidence yet to support long-held theories that repeated blows to the head may cause nerve-degenerative diseases like Lou Gehrig's disease and Alzheimer's.
Autopsies of 12 athletes who died with brain or neurological disease showed a distinctive pattern of nerve damage -- and fingered some potential culprits.
All had repeated concussions during their careers. Three of the men had been diagnosed with amyotrophic lateral sclerosis, also known as ALS or Lou Gehrig's disease, the star baseball player who died of it.
Experts in brain injury said the study, published in the Journal of Neuropathology & Experimental Neurology, pointed to new areas of research and possible ways to prevent long-term damage from concussions. (...)
Stressful Social Situations May Be Physically Harmful in Some
drugs.com 18.8.2010
WEDNESDAY, Aug. 18 -- Stress caused by social situations, such as giving a speech or going to a job interview, can affect some people's immune system in ways that harm their health, researchers have found.
The study included 124 volunteers who were purposely put into awkward social situations. Those who exhibited greater neural sensitivity to social rejection also had greater increases in inflammatory activity when exposed to social stress. (...)
The study was released online Aug. 2 in advance of publication in an upcoming print issue of the Proceedings of the National Academy of Sciences. (...)
Read more: http://www.drugs.com/news/stressful-social-situations-may-physically-harmful-some-26164.html#ixzz0wzoPMfJK
Kvinnor med mensvärk får förändringar i hjärnan
sverigesradio.se 13.8.2010
Kvinnors menssmärta förändrar hjärnan. Det har nu taiwanesiska forskare kunnat visa.
Tidigare har man bara vetat att konstant smärta påverkar hjärnan, men nu har man för första gången kunnat se att även om värken pågår under en kortare tid leder det till förändringar i hjärnan.
Att det inte har forskats mycket om kvinnor och menssmärta tidigare beror på att man inte velat utsätta fertila kvinnor för röntgenstrålning. Med ny teknik är det nu alltså möjligt att göra fördjupade studier. (...)
The Complexity of Complex PTSD
Editorial
Am J Psychiatry 167:879-881 (August)
Trauma-focused therapies, and cognitive-behavioral therapy (CBT) in particular, have become the treatment of choice for posttraumatic stress disorder (PTSD) over the past two decades (1). (...)
Complex PTSD is not formally recognized by DSM-IV, or the proposed DSM-5, as a distinct construct. Although DSM-IV lists emotion dysregulation as an associated feature of PTSD, the construct is generally conceptualized as a form of PTSD in which the patient has especially marked impairment in regulating their emotions, which results in maladaptive responses to extreme emotions, including self-harm, risky sexual or spending behavior, and chaotic interpersonal relationships (4). (...)
The Munchies, Marijuana and Happiness (Sultfølelsen, marihuana og lykke)
psychologytoday.com 28.7.2010
The munchies may be the key to understanding depression. (Sultfølelsen kan være nøkkelen til å forstå depresjon)
Why does smoking marijuana produce the munchies? What does this peculiar response tell us about our brain? It turns out, quite a lot; particularly with regard to our ability to experience happiness and joy and to avoid obesity and depression. The craving for food while smoking is likely due to the stimulation of marijuana receptors in the feeding centers of our brain. The munchies drew the attention of neuroscientists who then conducted a series of clinical trials using a novel drug, called rimonabant, that potently block the brain's marijuana receptors. Their hope was that blocking the action of the brain's marijuana neurotransmitter system in the feeding center would produce an "anti-munchies" effect, thereby reducing food consumption and providing help to overweight patients. Right from the beginning, the drug worked very well. People reported significantly fewer cravings for food. In addition, many subjects reported that they were also less interested in drinking alcohol, smoking cigarettes or using cocaine. Not surprising, excitement in the medical community grew quickly about the potential benefits that this drug might provide, particularly because obesity is such a major health risk. (...)
What these studies teach us is that our brain's own marijuana neurotransmitter system is necessary for us to feel hungry, to experience happiness and to maintain the brain normal processes, such as neurogenesis, that prevent age-associated depression and cognitive decline. We've learned from our experience with rimonabant that it is dangerous to constantly antagonize this neurotransmitter system. What we do not know is whether it is dangerous to constantly stimulate it. (...)
Slipper treningsspill for ansiktet
spillmagasinet.no 26.7.2010
Med «Face Training» til Nintendo DS lover Nintendo at du kan «bevare et ansikt som oser av livskraft og styrke». Kanskje litt som Demi Moore (47)?
- Bevar et ansikt som oser av livskraft og uttrykk, lover Nintendo.
Nintendo har hatt stor suksess med hjernetrimspillet «Brain Training», og nå lanserer spillgiganten «Face Training» på det europeiske markedet.
- Har du følt deg litt stresset i det siste? Nå kan du styrke og løse opp seks forskjellige områder i ansiktet ditt gjennom enkle, daglige øvelser med «Face Training», skriver Nintendo i en pressemelding. (...)
Chemical Grows Brain Cells? (Kjemikalier kan utvikle nye hjerneceller)
ivanhoe.com 21.7.2010
(Ivanhoe Newswire) -- It sounds like science-fiction, but researchers have identified a chemical that causes brain cells to grow.
Investigators from the University of Texas Southwestern say the substance -- known as P7C3 -- can actually make new neurons grow. They came to this conclusion after infusing 1,000 different chemicals into the brains of live mice. (...)
Brain Function Differs With Weight, Body Shape (Hjernefunksjonvarierer med vekt, kroppsform)
medpagetoday.com 16.7.2010
Body mass index and the distribution of fat were both associated with cognitive function in a large study of postmenopausal women, researchers said.
In women with a low waist-to-hip ratio -- denoting a "pear-shaped" body -- increasing BMI correlated significantly with poorer cognitive performance, according to Diana R. Kerwin, MD, of Northwestern University in Chicago, and colleagues.
Meanwhile, the "apple shape" with fat concentrated at the waist made higher BMI predictive of relatively better cognition, the researchers found. (...)
Blame your serotonin levels for being a crybaby (Skyld på dine serotoninnivåer om du er en skrikerunge)
dnaindia.com 16.7.2010
Washington, DC: Always end up crying while watching a movie high on emotional quotient? Well, blame your serotonin levels for it, says a new study.
Frederick van der Veen of the Erasmus Medical Centre and colleagues have found that due to the differences in the neurotransmitter some people are more likely to cry in emotional situations than others.
The researchers gave 25 female volunteers a single dose of either paroxetine - a selective serotonin reuptake inhibitor (SSRI) that briefly increases serotonin levels - or a placebo. (...)
Bit of a crybaby? Blame your serotonin levels (Bitt av en skrikerunge? Skyld på dine serotoninivåer)
newscientist.com 15.7.2010
(...) Although SSRIs are used to treat depression, their mood-boosting effects do not normally show up for around six weeks. The women reported no change in mood in the current study. "We're looking at the direct effect of a single dose of paroxetine," says van der Veen, who adds that the findings might help explain why some people report blunted emotions when taking SSRIs.
"Our understanding of the neurobiology of crying is fairly limited," says Christopher Lowry, a serotonin researcher at the University of Boulder in Colorado. "It makes sense that it is tapping into circuitry involving serotonin."
Van der Veen now wants to find out whether genetic differences in serotonin production affect the tendency to cry. (...)
– Depresjon kan doble risikoen for demens
aftenposten.no 6.7.2010
Lider du av depresjon, kan faren for at du rammes av demens seinere i livet være dobbelt så høy som normalt, viser ny forskning.
Eksperter har lenge visst at demens og depresjon ofte sammenfaller, men det har ikke vært klart at den ene tilstanden leder til den andre.
Nå viser to studier publisert i tidsskriftet American journal Neurology at depresjon i en fase av livet gjør det mer sannsynlig at man utvikler demens senere, melder BBC.
Men forskerne bak rapportene vet fortsatt ikke årsaken til koblingen mellom depresjon og demens, og de understreker at det trengs mer forskning for å fastslå en sikrere årsakssammenheng. (...)
Hjernens kjemi
Forskerne har blant annet sett på hjernens kjemiske sammensetning, livsstilsfaktorer og sosial omgang.
«Betent hjernevev forårsaket av depresjon kan føre til demens. Enkelte proteiner man har funnet i hjernen som øker i antall med depresjon, kan også forårsake demens», heter det i en av studiene.
I den ene av studiene er 949 eldre personer fulgt over en periode på 17 år. 164 hadde utviklet demens. 22 prosent av de som hadde oppgitt depresjon som lidelse tidligere i livet hadde utviklet demens. Av dem som ikke hadde hatt depresjon, var det 17 prosent som fikk demens senere i livet. (...)
Brain patterns may be signs of mental illness risk
reuters.com 2.7.2010
(Reuters) - British scientists believe they have found specific patterns of brain activity in children and young people which could be signs or "markers" of those who will later go on to develop mental illnesses such as schizophrenia.
Researchers from Nottingham University, who presented their study at the Forum for European Neuroscience in Amsterdam, said the patterns suggest it may be possible in future to identify those at risk of becoming ill before they develop symptoms. (...)
Forbudt skisse skjult i Michelangelos mesterverk
nrk.no 26.6.2010
Etter 500 år har forskere oppdaget en menneskehjerne på motivet av Guds hals i det sixtinske kapell. Michelangelo angrep Kirken ved å gjemme forbudte anatomiske skisser i maleriene.
Medisinske forskere fra Baltimore i USA tror Michelangelo skjulte forbudte skisser av menneskehjernen i Det Sixtinske kapell i Vatikanet. Et av motivene i taket forestiller Gud som skiller dag fra natt, og på halsen til Gud oppdaget de noe forbløffende:
– Ved å følge Michelangelos linjer i halsen og skjegget, kan man helt praktfullt tegne inn en korrekt gjengivelse av en del av hjernen”, skriver Ian Suk and Rafael Tamargo sin artikkel i tidskriftet Neurosurgery. (...)
•Undersøk detaljene selv: Se det sixtinske kapell i 360
•LES OGSÅ: Michelangelo skjulte flere skisser (...)
Study Shows Courage Sparks Certain Parts of Brain
health.msn.com 23.6.2010
Finding could lead to treatment for fear, researchers say
WEDNESDAY, June 23 (HealthDay News) -- Scientists have uncovered new details about brain mechanisms associated with courage.
Israeli researchers used functional MRI to scan brain activity in volunteers as they decided whether to move either a toy bear or a live corn snake closer or farther away from them. Prior to the study, the participants had been classified as "fearful" or "fearless" based on a questionnaire about snake fears. (...)
Også moderat hjerneskade kan gi men
Tidsskr Nor Legeforen 2010; 130:1216 (17.6.2010)
Pasienter med moderate traumatiske hjerneskader bør følges opp bedre, både rett etter skaden og på lang sikt. Mange sliter med dårlig helse ett år etter skaden, og etter ti år er 30 % uføre.
Nada Hadzic-Andelic har undersøkt forekomsten av akutte traumatiske hjerneskader i Oslo (se ordforklaringer), og også studert funksjonsutfall og helserelatert livskvalitet blant voksne i alderen 16–55 år, alle med moderat til alvorlig traumatisk hjerneskade.
– Pasientene, også flere av dem med mindre alvorlige skader, rapporterte om stor grad av uførhet og dårlig helse ett år etter hodeskaden. Hver fjerde pasient trengte hjelp til daglige aktiviteter, blant annet fordi de var blitt rotete og glemsomme. Etter ti år var de fleste pasientene i relativt god form, både fysisk og kognitivt, men hadde likevel nedsatt livskvalitet sammenliknet med den generelle befolkningen, sier Hadzic-Andelic.
Hun mener at også pasienter med mindre alvorlige hjerneskader bør få tilbud om strukturert rehabilitering etter utskrivning fra sykehus. (...)
Systematic Review: NIH State-of-the-Science Conference: Factors Associated With Risk for and Possible Prevention of Cognitive Decline in Later Life
Ann Intern Med 2010 (June 14)
Background: Many biological, behavioral, social, and environmental factors may contribute to the delay or prevention of cognitive decline.
Purpose: To summarize evidence about putative risk and protective factors for cognitive decline in older adults and the effects of interventions for preserving cognition. (...)
Limitations: The categorization and definition of exposures were heterogeneous. Few studies were designed a priori to assess associations between specific exposures and cognitive decline. The review only included English-language studies, prioritized categorical outcomes, and excluded small studies.
Conclusion: Few potentially beneficial factors were identified from the evidence on risk or protective factors associated with cognitive decline, but the overall quality of the evidence was low. (...)
Daniel (31) husker 22 000 desimaler av PI
dagbladet.no 7.6.2010
Og lærte seg islandsk på en uke.
(Dagbladet): Britiske Daniel Tammet har diagnosen Savant-syndrom. En sjelden lidelse eller tilstand der personen utvikler nærmest overmenneskelige evner innen musikk, matematikk, kunst og spesielt hukommelse.
31-åringen kan åtte språk, men det er ikke bare ord som fester seg i Tammets hjerne. Han husker også tall som en supercomputer.
Ifølge en video publisert på amerikanske ABC News skal Tammet ha studert PI en gang og memorert 20 000 desimaler. (...)
En av verdens fremste eksperter på savanter, Darold Treffert, mener Savant-syndromet kan peke mot ubrukte evner hos alle mennesker. Treffert ble brukt som konsulent på filmen Rain Man og mener savant syndromet gir et unikt innsyn i menneskehjernen.
- Før vi kan forklare savanter, kan vi ikke forklare oss selv, skriver Treffert i en artikkel på sine hjemmesider. (...)
Ungdomsfylla skader hukommelsen
nrk.no 3.6.2010
Gjentatte fyllekuler i ungdomsårene kan gi varige skader på hjernen, viser en ny studie. (...)
- Dette er alvorlig. Og det som er nytt for meg, er at det ser ut til at fornyelsen av hjerneceller blir kraftig redusert, sier rusforsker og direktør Jørg Mørland ved Folkehelsa til NRK Verdt å vite. (...)
Apene som fikk alkohol, drakk seg beruset hver dag i 11 måneder. (...)
Svikt på viktige områder
Undersøkelsene viste at deler av hjernen som skoleungdom sårt trenger til eksamen, blir skadet ved stadige fyllekuler.
- Forandringene skjer i en del av hjernen som heter hippocampus. Den er viktig for innlæring og hukommelse, og et ett av de få stedene der det stadig dannes nye hjerneceller, forteller Mørland.
Det er tidligere gjort en rekke observasjoner av dyr og mennesker som tyder på at alkohol kan gå utover blant annet hukommelse, innlæring, kognitive funksjoner, impulskontroll og evnen til å gjøre riktige valg til riktig tid.
- Studien fra California forklarer mulige mekanismer for det vi har sett i andre studier, sier Mørland. (...)
Elderly Falls Linked to Altered Blood Flow in Brain
news.yahoo.com 18.5.2010
TUESDAY, May 18 (HealthDay News) -- High blood pressure can alter the flow of blood in the brain and lead to falls among the elderly, new research suggests.
The findings stem from research led by Dr. Farzaneh A. Sorond of Brigham and Women's Hospital, Hebrew SeniorLife's Institute for Aging Research and Harvard Medical School in Boston. (...)
In the May 18 issue of Neurology, the authors report that those seniors who were among the 20 percent of participants who experienced the smallest brain blood flow changes were 70 percent more likely to fall than those among the 20 percent with the largest brain blood flow changes.
In other words, those with the highest blood flow rate fell on average fewer than once per year, while those with the smallest blood flow rate fell almost 1.5 times per year.
"At age 60, 85 percent of people have a normal walking ability," Sorond said in a news release. "However, by age 85, only 18 percent of seniors can walk normally."
"Our findings suggest there could be a new strategy for preventing falls, such as daily exercise and treatments for high blood pressure, since blood pressure affects blood flow in the brain and may cause falls," she added. (...)
Depression var vanligt efter traumatisk hjärnskada
dagensmedicin.se 19.5.2010
Mer än varannan person som fått en traumatisk hjärnskada drabbades av en allvarligare depression året efter skadan, enligt en ny studie.
Forskare vid University of Washington i Seattle, USA, följde upp 559 patienter med strukturerade telefonintervjuer en, sex, åtta, tio och tolv månader efter att de hade drabbats en traumatisk hjärnskada. (...)
Biologisk koppling mellan kreativitet och schizofreni
sverigesradio.se 18.5.2010
Att kreativitet och psykisk sjukdom hänger ihop är en gammal sanning - redan Aristoteles lär ha sagt "inget geni utan ett visst mått av galenskap". Nu har forskare vid Karolinska Institutet i Stockholm hittat en biologisk koppling mellan kreativitet och schizofreni. (...)
Schizofrenpatineter saknar bland annat en mängd celler som reagerar på signalsubstansen dopamin i en viktig del av hjärna, thalamus. Det är i thalamus sinnesintrycken sorteras. Forskarna bakom den aktuella studien undersökte hur det ser ut i hjärnan på helt friska, men mycket kreativa individer. Och de fann ett samband. (...)
Kanske är det så, resonerar forskarna, att hjärnan hos såväl schizofrena som extremt kreativa människor är dålig på att sortera bort sinnesintryck, på grund av bristen på dopaminreceptorer i thalamus. Hos den kreativa leder det till idérikedom men hos den svårt psykiskt sjuka till förvirring. Även bipolär sjukdom kan kopplas på ett liknande sätt till kreativitet. (...)
Brain Repair after Stroke
NEJM 2010; 362(19):1827-1829 (May 13)
Stroke is the second leading cause of death worldwide. A majority of patients survive stroke, however, making this disorder a major source of human disability. Although most patients have some spontaneous behavioral improvements after a stroke, the recovery is generally incomplete. Compounding this burden of disability is the fact that one in four patients who have a stroke is under 65 years of age.
An emerging approach to reducing the degree of disability after a stroke focuses on brain repair. Repair therapies aim to restore the brain, a goal that differs from that of neuroprotection therapies, in which the aim is to limit acute stroke injury. A number of repair-related therapies have been defined in preclinical studies. Such therapies can produce enduring behavioral gains when introduced days to months after the onset of stroke. Several classes of therapy are under study for brain repair, including the use of stem cells, growth factors, small molecules, electromagnetic stimulation, and intensive physiotherapy.1 Many of these therapies, including robot-based physiotherapy,2 are already in human trials. (...)
Brain Region's Dopamine Levels Linked to Psychopathy Trait (Hjerneregioners dopaminnivåer linket til psykopatiske karaktertrekk)
Psychiatr News 2010;45(9):1 (May 7) (American Psychiatric Association)
Just as deficits in the amygdala and prefrontal cortex may prompt antisocial people to be fearless and lack empathy, an overly responsive nucleus accumbens may prompt them to be aggressive.
Ah, the “bad guy” is thinking, “I'm going to take that sucker for all he's worth.”
What's going on in his brain? His brain's reward center—the nucleus accumbens—may be goading him into action, a new study suggests.
The study found a link between the personality trait of psychopathy and an overly responsive nucleus accumbens.
Joshua Buckholtz, a doctoral candidate in neuroscience at Vanderbilt University, headed the study. Results were reported online March 14 in Nature Neuroscience. (...)
The personality trait of psychopathy is characterized by charm, egocentricity, manipulation of others, sensation-seeking, poor reflection, and blunted empathy. Psychopathy in turn is a robust predictor of antisocial behavior.
Moreover, alcohol, nicotine, and many other drugs of abuse are known to stimulate the nucleus accumbens, and psychopathic individuals are known to be at heightened risk for developing substance abuse problems. So Buckholtz and his colleagues suspected that there might be a link between the personality trait of psychopathy and the nucleus accumbens. They conducted a study to find out. (...)
Fountain of Youth For Your Brain
ivanhoe.com 7.5.2010
SALT LAKE CITY, Utah (Ivanhoe Newswire) -- You walk into a room and can't remember why. Sound familiar? Research shows that once we turn 25, our brains slow production of chemicals linked to memory. Now, a new supplement can help keep your memory sharp! (...)
She's right. Deborah Yurgelun-Todd, Ph.D., a psychiatrist at the University of Utah's Brain Institute in Salt Lake City, says after age 25 our brains start to shrink, losing chemicals called neurotransmitters that help with memory.
She did a study where people took 500 to 2,000 milligrams of cognizin citicoline for six weeks. All of them showed significant increases in memory with no side effects.
"What we did, which was not done before, was to look at actual metabolic changes in the brain after supplementation, and therefore could show this is not just 'a feeling I have,' but a feeling linked to a physiological change," Dr. Yurgelun-Todd explained.
Lisa already notices a difference. (...)
Hjernen og følelser – fra barn til voksen
Tidsskr Nor Legeforen 2010; 130:932-5 (6.5.2010)
Bakgrunn. Moderne nevrovitenskap knytter menneskers atferd, følelser og tanker til nevrobiologiske prosesser i hjernen. Bedre kunnskap om slike sammenhenger kan øke forståelsen for emosjonelle reguleringsproblemer hos barn og ungdom og utvikling av psykopatologi i noen tilfeller. (...)
Fortolkning. Emosjonsregulering dannes i et komplekst samspill mellom barnets relasjoner, erfaringer og handlinger og dets biologiske og genetiske egenskaper. Å kjenne til det biologiske grunnlaget kan hjelpe til bedre å forstå typiske atferdstrekk ved ulike alderstrinn og barn som har problemer med å regulere sine følelser. Å kartlegge spesifikke genetiske eller miljømessige faktorer som kan hjelpe barn og unge til å håndtere egne følelser, kan også være viktig for å utvikle terapiformer som fremmer tilstrekkelig emosjonsregulering. (...)
Slik husker du ny informasjon
nettavisen.no 18.4.2010
Har du vanskeligheter med å lære noe nytt eller få ny kunnskap til å sitte? Se hva forskerne anbefaler.
Vil du være lat og produktiv på samme tid, kan det være en god idé å ta seg en lur. Nyere forskning viser nemlig at det å sove litt forbedrer læringen.
Professor Matthew Walker fra U.C. Berkeley avslørte dette funnet under «the American Association for the Advancement of Science» -konferansen i San Diego nylig. (...)
Grunnen til dette er at når man sover så tømmes hippocampus - eller det vi kaller korttidshukommelsen. Minnene forflyttes fra Hippocampus til en annen lagringsplass i hjernen, og deretter til en annen, helt til de til slutt ender opp i Cortexen. Cortexen regnes for å være hjernens store harddisk, hvor alle minner til slutt lagres.
Etter en liten formiddagslur er altså Hippocampusen tømt for informasjon, og du er klar for å lære nye ting eller ta imot ny informasjon som du kan fylle den opp med. (...)
Känslor behöver inte minnen
svt.se 13.4.2010
Glädje och sorg kan finnas kvar trots att minnet av det som skapade känslan har utplånats. Vi behöver inte minnesförmåga för att hålla kvar en sinnesstämning, visar forskning som kan få betydelse för vården av dementa. (...)
Skratt och tårar
Men faktum är att människan inte enbart förlitar sig på minnet av en specifik händelse för att känna lycka eller bedrövelse efteråt. Detta visar en studie från forskarna Justin Feinstein, Melissa Duff och Daniel Tranel vid University of Iowa.
De har gjort en liten, men välgjord och unik studie, bland fem personer som är i det närmaste oförmögna att lagra nya minnen på grund av skada i hippocampus, en struktur i hjärnan som är central för minneslagring. En hippocampusskada kan ge samma effekt på minnet som svår alzheimer, men utan de övriga symtomen. (...)
Fet mat er som kokain
vg.no 6.4.2010
Fet mat kan forårsake kokainlignende avhengighet.
Forskere har endelig bekreftet hva mange av oss har hatt mistanke om: Bacon, ostekake, og andre fetende matvarer kan være vanedannende.
En ny studie på rotter antyder at høyt innhold av fett og kalorier påvirker hjernen på samme måte som kokain og heroin. Når rottene spiser disse matvarene i store nok mengder, fører det til spisevaner som ligner narkotikaavhengighet, melder nettstedet Health.com.
Lykkestoff
Det er dopamin som ser ut til å være ansvarlig for overspisingen. Lykkestoffet skilles ut i hjernen ved lystbetont aktivitet, og fet mat kan dermed betraktes som et rusmiddel man blir avhengig av. (...)
Scientists find aging gene is linked to immunity (Forskere finner aldringsgen linket til immunitet)
reuters.com 30.3.2010
Reuters) - British scientists studying the genetics of aging said on Thursday that experiments on laboratory worms showed that a specific gene is strongly linked to lifespan, immunity and disease resistance.
Since the gene, called DAF-16 in worms, is found in many animals and in humans, the finding could open up new ways to affect aging, immunity and resistance in humans, the scientists said.
"We wanted to find out how normal aging is being governed by genes and what effect these genes have on other traits, such as immunity," said Robin May of the University of Birmingham, who led the study. (...)
Gravide blir glemske og sure
nrk.no 26.3.2010
Ny forskning viser at gravide ikke bare blir i dårligere humør - de husker også mindre enn andre. (...)
Hormonene har skylden?
Det er usikkert hva som har skylden for at hukommelsen svikter.
Hjernedelen hippocampus styrer spesielt vår romlige oppfattelse. Hvis hormonnivåene endres, slik som under graviditeten, kan nok dette påvirke måten hippocampus fungerer på, tror forskerne.
Forandringer i humøret og økt angst kan også påvirke hukommelsen. (...)
New study highlights immune system's role in Alzheimer's
pharmanews.eu 26.3.2010
The brain's immune cells may be behind the loss of neurons associated with Alzheimer's disease, new EU-funded research suggests. The findings, published in the journal Nature Neuroscience, could lead to the development of new treatments for the neurodegenerative disease. (...)
Støv på hjernen
Av Dag O. Hessen
morgenbladet.no 26.3.2010
Hvorfor er det ikke biologene som svinger kosten i Harald Eias Hjernevask?
En vitsetegning til bruk for selvironiske biologer viser forskeren som opprømt kommer løpende inn til sine kolleger, sindig bøyd over reagensrør og mikroskoper, mens han utbryter: «Eureka. Jeg har oppdaget genet som får oss til å tro at alt ligger i genene.»
Biologiske forklaringer på menneskelig gjøren og laden har slitt med dårlig ry av historiske årsaker, og det er fortsatt en vanlig oppfatning at biologien har lite av gode nyheter å bringe til torgs når det gjelder mennesket generelt, og kvinner spesielt. En del av det dårlige omdømmet er forståelig, noe er fortjent, men mye bygger på en utdatert og unyansert oppfatning av gener og biologi. Om vi nå for det første tar inn over oss at «den menneskelige natur» er fleksibel, og at sosialitet og empati er like evolusjonært naturlige trekk ved mennesket som aggresjon og egoisme, og om vi i tillegg makter å skille den ideologisk betente sosialdarwinismen fra dagens biologi og evolusjonspsykologi, da har vi lagt grunnlaget for en mer konstruktiv meningsutveksling. (...)
Telomere Diseases
NEJM 2010;362(12):1150 (March 25)
To the Editor: The review article by Calado and Young (Dec. 10 issue)1 discusses the influence of aging, cancer, cardiopulmonary disease, and disorders of the liver and skin on telomere disorders but ignores autoimmunity and the immune system. Our group and others have shown that antibodies to telomere (which is pure double-stranded DNA) correlate with lupus disease activity and that telomere lengths in lymphocytes are shortened in patients with systemic lupus erythematosus, scleroderma, and rheumatoid arthritis.2, 3, 4 In a recent study,5 investigators hypothesized that telomerase insufficiency results in excessive T-cell loss, undermining homeostatic control of the naive T-cell compartment and leading to lymphocytopenia-induced remodeling of the T-cell repertoire. Thus, telomerase insufficiency has emerged as a therapeutic target for resetting immune abnormalities in patients with autoimmune disorders. (...)
'Super-Aged' People Escape Memory Loss
ivanhoe.com 24.3.2010
(Ivanhoe Newswire) -- Evidence that some elderly brains are immune to the "tangles" linked to memory loss challenges the idea that mental decline is a normal part of aging.
In a new study focusing on what's right in the brains of older people rather than what's wrong, researchers found some elderly individuals with super-sharp memories altogether escaped the formation of tangles associated with memory loss. (...)
New Findings Boost Theory That Infection Causes Schizophrenia (Nye funn styrker teorien om at infeksjoner forårsaker skizofreni)
Psychiatr News 2010;45(6):1 (March 19) (American Psychiatric Association)
A review of studies of maternal exposure to infectious agents and schizophrenia in their offspring suggests that eliminating certain infections could prevent as many as 30 percent of schizophrenia cases.
Call it an instance of science being stranger than science fiction, and of nature's unintended consequences.
In 2000, a team of British researchers published a remarkable paper in the journal of the Royal Society titled “Fatal Attraction in Rats Affected With Toxoplasma Gondii.” It seems that rodents infected with Toxoplasmosis gondi (T. gondii), a parasite that normally thrives in cats, become fatally attracted to cat urine, causing them to shed their normal avoidant behavior in the presence of a cat. (...)
Can Infection-Related Schizophrenia be Prevented? (Kan infeksjonsrelatert skizofreni forhindres?)
Psychiatr News 2010;45(6):19 (March 19) (American Psychiatric Association)
The identification of T. gondii and other infectious agents as possible factors in schizophrenia has implications for prevention and treatment.
In their review of studies in AJP in Advance on infectious agents including T. gondii and the development of schizophrenia, Alan Brown, M.D., and colleagues noted that “many genital/reproductive system microbes are readily eliminated by antibiotics. Hence, increased surveillance and treatment of the reproductive-age population for these infections may have the potential to reduce the risk of schizophrenia.... (...)
Brain Chemical Linked to Cognitive Decline in Schizophrenia
ivanhoe.com 15.3.2010
(Ivanhoe Newswire) -- The delusions and hallucinations associated with schizophrenia may be linked to a deficit in a brain chemical. (...)
Psychosis is treated with a variety of antipsychotic medications that dampen over-activity of the neurotransmitter dopamine, an acknowledged cause of psychotic behavior. But no medications are available to address cognitive deficits in schizophrenia because the source of the deficits has not been identified. Research involving animal models and post-mortem analyses of the neurotransmitter gamma-aminobutyric acid, or GABA, suggest that deficits in GABA may play a causal role in the cognitive difficulties experienced by people with schizophrenia. (...)
Hjerneskanning kan hjelpe schizofrene
forskning.no 11.3.2010
En ny dansk undersøkelse har lokalisert endringer i hjernen på pasienter med schizofreni. Det gir håp om raskere og mer presis behandling. (...)
Det kan ta lang tid å finne ut om et preparat virker, og etter mange ukers forgjeves behandling må pasienten ofte starte forfra med en ny medisin som kanskje heller ikke virker. (...)
Biologiske endringer
Undersøkelsen er publisert i «Archives of General Psychiatry». Ved hjelp av en rekke hjerneskanninger gir forskerne et innblikk i de biologiske endringene i hjernen hos pasienter som lider av schizofreni.
– Det er nøyaktig det samme som med kreftbehandling, forklarer Thomas Werge, som er forskningssjef ved Sankt Hans Hospital.
– Hvis vi vil behandle sykdommen, må vi vite hvor den sitter, og vi må så tidlig som mulig kunne holde øye med om behandlingen virker. (...)
De har undersøkt en gruppe reseptorer i hjernen (se faktaboks), nærmere bestemt den undergruppen som heter serotonin 2A-reseptorer, som påvirkes av mange antipsykotiske medikamenter.
Serotonin er et signalstoff i hjernen, som populært (men upresist) er blitt døpt «lykkestoff» fordi det har vist seg å spille en rolle ved blant annet depresjon.
Nettopp serotonin 2A-reseptoren har tidligere vært diskutert i forbindelse med schizofreni. (...)
Nikotintoppar mer sällsynta
hos rökare än man trott
sr.se 9.3.2010
Nikotinet når rökarens hjärna långsammare än vad man tidigare trott. Det gör att nikotinnivån är som allra högst i hjärnan i slutet av en cigarett – och alltså inte når toppar efter varje bloss.
Tidigare trodde forskarna att varje cigarettbloss ledde till en nikotintopp i hjärnan bara sju sekunder senare, och att denna omedelbara men kortsiktiga effekt kunde förklara varför cigaretter är mer beroendeframkallande än substitut som till exempel nikotinplåster eller tuggummin.
Men den här nya studien, som publiceras i den amerikanska vetenskapsakademiens tidskrift PNAS, visar alltså att nikotinhalten stadigt ökar i hjärnan under hela tiden som rökaren suger i sig en cigarett.
Forskarna hoppas nu att de nya rönen ska leda till effektivare behandlingsmetoder mot cigarettberoende. (...)
Blindness may Start in the Brain (Blindhet starter i hjernen)
ivanhoe.com 3.3.2010
(Ivanhoe Newswire) -- Glaucoma is a leading cause of blindness in the United States, but now researchers are one step closer to understanding the disease.
Glaucoma is a disease of the eye in which the retina and optic nerve are damaged. The damage begins in the peripheral visual field and progresses toward the center, causing complete blindness if it's not detected early.
The National Eye Institute predicts 80 million people will suffer from glaucoma in the next 10 years. People over the age of 55 with glaucoma are seven times more likely to develop vision loss as a result of the condition. (...)
Thymus Could Be the Key to Vaccine Against Diabetes and Cure for Autoimmune Diseases
nanopatentsandinnovations.blogspot.com 26.2.2010
The newest, most original approach to preventing and curing autoimmune diseases, with a specific focus on diabetes 1, is based on the major biological functions of the thymus, an organ located just behind the breastbone (...)
The 25 partners of the European consortium EURO-THYMAIDE (THYMus in AutoImmunity DEvelopment) have been working across 12 countries on this novel paradigm of the pathogenesis of autoimmunity, namely that a defect in the thymus is a major event in contributing to different autoimmune diseases. (...)
Scientists Unravel Mysteries of Intelligence
drugs.com 26.2.2010
FRIDAY, Feb. 26 -- It's not a particular brain region that makes someone smart or not smart.
Nor is it the strength and speed of the connections throughout the brain or such features as total brain volume.
Instead, new research shows, it's the connections between very specific areas of the brain that determine intelligence and often, by extension, how well someone does in life. (...)
Concussions: Lasting Brain Injury (Hjernerystelser: Varig hjerneskade)
Ivanhoe.com 22.2.2010
(Ivanhoe Newswire) -- More than 1 million people suffer them in the United States every year, but now researchers say concussions may be more dangerous than you think.
Mild traumatic brain injury (mTBI), also widely referred to as concussions, are often ignored as a major health problem, but now a new study shows they can carry major health complications. (...)
The researchers believe the stretching and disconnecting of nerve-cell axons after a concussion result in changes to the sodium channels of neurons. (...)
SÅ lite skiller oss fra sjimpansene
vg.no 20.2.2010
Genetisk er mennesker og sjimpanser nesten like. Den store forskjellen skyldes at våre gener er flinkere til å danne nettverk, viser en norsk-amerikansk studie.
Mer enn 97 prosent av menneskets genmateriale er identisk med sjimpansens. Hvorfor er vi da så ulike?
Svaret ligger ikke i genene som sådan, men hvordan genene arbeider og samhandler, forklarer NTNU-professor Eivind Almaas til forskningsmagasinet Gemini. (...)
Transkripsjonsfaktorenes jobb i hjernen er å danne nettverk. Eivind Almaas utviklet et nettverksdiagram som viser hvordan disse genene påvirker hverandre. Menneskets hjernenettverk ligner i store trekk på sjimpansens, men det er langt tettere, og samhandlingen er større. (...)
- Kan forutse skoleproblemer hos babyer
vg.no 17.2.2010
Funnene er gjort i en stor studie som omfatter nesten 15.000 barn.
Studien viser at barn som ni måneder gamle ikke hadde nådd motoriske milepæler - som å sitte på egen hånd, krabbe eller holde gjenstander med fingrene - scoret dårligere på tester gjort når de var fem år gamle. Disse testene omfattet blant annet vokabular og romforståelse, skriver The Guardian. (...)
Scientists Pinpoint Area of Brain That Fears Losing Money
businessweek.com 10.2.2010
Those with damaged amygdala had no aversions to risky gambles, study found (...)
The study appears in this week's issue of the Proceedings of the National Academy of Sciences. (...)
Test viser risiko for hjerneslag
nrk.no 4.2.2010
En enkel test kan avgjøre om du er i risikosonen for å få hjerneslag når du blir eldre.
Med en enkel test har forskere fra Uppsala funnet en sammenheng med risikoen for hjerneslag skriver Sveriges Radio.
Testen måler visuelt overblikk, raskhet og evnen til å ha flere baller i luften. Tiden du bruker på testen vil vise om du er i risikogruppen.
Ta testen her:
Test din risiko for hjerneinfarkt (...)
Skader på blodkar dypt i hjernen kan svekke den mentale kapasiteten og samtidig sette deg i risikosonen for blodpropp. (...)
Leste tankene til hjerneskadet mann
vg.no 4.2.2010
(VG Nett) Etter syv år uten å ha kommunisert med omverdenen klarte forskere å snakke med den sterkt hjerneskadede mannen.
Forskerne var mildt sagt forbauset da mannen ingen trodde hadde bevissthet plutselig klarte å svare på en rekke spørsmål bare ved hjelp av å styre tankene sine.
Ifølge BBC så har forskerne sett på fMRI-skanner av hjernen og målt hjerneaktivitet i området hos pasienter i en såkalt vegetativ tilstand.
Hos de aller fleste pasientene som var med i forsøket var det ingen tegn til bevissthet, mens fire av 23 pasienter overrasket forskerne. (...)
Sömnapné kan skada hjärnbarken
aftonbladet.se 1.2.2010
Återkommande långa andningsuppehåll under sömnen kan leda till att antalet celler i hjärnan minskar.
Den svåra sömnapnén är en möjlig orsak till minnesstörningar och sämre tankeförmåga, visar nya forskningsresultat.
– Absolut kan det vara så. Om antalet celler i den tänkande delen av hjärnan minskar måste det få sådana konsekvenser, säger stressforskaren Torbjörn Åkerstedt.
En forskargrupp från Sydkorea presenterar de nya rönen i den vetenskapliga tidskriften Sleep. (...)
Exercise Builds Brain Volume in Schizophrenia (Trening øker hjernevolum hos skizofrene)
medpagetoday.com 1.2.2010
Three months of aerobic exercise significantly increased the volume of the hippocampus in patients with chronic schizophrenia, researchers said.
The increase was accompanied by "modest" increases in short-term memory and markers of neuron production, according to Frank-Gerald Pajonk, MD, of Dr K. Fontheim's Hospital for Mental Health in Liebenburg, Germany, and colleagues.
But it's too early to say whether incorporating aerobic exercise into treatment programs might reduce the disability associated with schizophrenia, the researchers said in the February Archives of General Psychiatry. (...)
Hippocampal Plasticity in Response to Exercise in Schizophrenia (Plastisitet i hippocampus som respons til trening ved skizofreni)
Arch Gen Psychiatry. 2010;67(2):133-143 (February)
Context Hippocampal volume is lower than expected in patients with schizophrenia; however, whether this represents a fixed deficit is uncertain. Exercise is a stimulus to hippocampal plasticity.
Objective To determine whether hippocampal volume would increase with exercise in humans and whether this effect would be related to improved aerobic fitness. (...)
Konklusjon Disse resultater indikerer at volum av hippocampus er plastisk både hos friske mennesker og pasienter med skizofreni (Conclusion These results indicate that in both healthy subjects and patients with schizophrenia hippocampal volume is plastic in response to aerobic exercise.) (...)
Dyr kan lege seg selv
MARKUS LINDHOLM- Biolog og PhD, Nesodden
aftenposten.no 29.1.2010
Sjimpanser kan forlate flokken sin for å oppsøke en helt bestemt urt, skriver Markus Lindholm. (...)
MEDISINERING. Nye forskningsfunn rokker ved forestillingen om at bare «den beste» overlever. (...)
Premature Aging of the Brain Seen in HIV Patients (For tidlig aldring av hjernen registrert hos HIV-pasienter)
usnews.com 26.1.2010
TUESDAY, Jan. 26 (HealthDay News) -- Premature aging is striking the brains of people infected with the virus that causes AIDS, new research suggests.
Det er ikke klart om viruset eller legemidler som behandler det -- eller begge -- bidrar til aldringen. (...) (It's not clear if the virus or the drugs that treat it -- or both -- are contributing to the aging.)
"The graying of the AIDS patient community makes this infection's effects on the brain a significant source of concern," study author Dr. Beau Ances, an assistant professor of neurology at Washington University in St. Louis, said in a university news release. (...)
HIV infection linked to aging of the brain (HIV-infeksjon linket til aldring av hjernen)
timesofindia.indiatimes.com 22.1.2010
HIV infection and its treatments are leading to premature aging of human brains, say researchers. (...)
"Patients are surviving into their senior years, and a number of them are coming forward to express concerns about problems they're having with memory and other cognitive functions. (...)
Når forskerne spurte deltakerne om å utføre visuell oppgave, som normalt trigger økning av blodgjennomstrømning til spesielle regioner av hjernen involvert i oppgaven, hadde deltakerne med HIV større økning i blodgjennomstrømning, hvilket indikerer at hjernen og støttessystemer måtte arbeide hardere for å få utført oppgaven. (When scientists asked participants to perform a visual task, which normally triggers an increase in blood flow to particular regions of the brain involved in the task, participants with HIV had greater blood flow increases, suggesting the brain and its support systems had to work harder to get the task done.)
"Blodgjennomstrømning i hjerne reduseres naturlig med alderen, men HIV, som vi bruker for å kontrollere den eller en kombinasjon av de to synes å akselerere denne prosessen uavhengig av aldring," tilføyde Ances . (...) ("Brain blood flow levels decline naturally as we age, but HIV, the medications we use to control it or some combination of the two appear to be accelerating this process independent of aging," Ances added.)
Hjernen takler ikke alle Facebook-vennene
vg.no 24.1.2010
(VG Nett) Selv om du har mange venner på Facebook, klarer ikke hjernen din å holde orden på mer enn 150 personer. (...)
Professor Robin Dunbar ved Universitet i Oxford fastslo allerede på 90-tallet at det maksimalt var plass til 150 venner i neocortex. Det er den delen av hjernen som holder orden på bevisste tanker og språk.
Begrensningen ligger i hjernen, og gjelder samme hvor sosiale vi er, skriver Sunday Times. (...)
Scientists Read Brain's Magnetic Fields to Spot PTSD
medicinenet.com 22.1.2010
THURSDAY, Jan. 21 (HealthDay News) -- For the first time, researchers have been able to diagnose post-traumatic stress disorder (PTSD) by reading patterns of magnetic fields created by brain cells. (...)
"Brain cells communicate with electrical signals," explained study author Dr. Apostolos P. Georgopoulos, whose team reported its work in the Jan. 20 issue of the Journal of Neural Engineering. "These electrical signals can be recorded with EEG, but they get distorted going through the skull and are delayed, so they're not very useful. The same electrical signals generate a magnetic field around them which passes out of the skull undistorted and extremely fast. They can be recorded with this instrument we have, so we have a very accurate, very faithful signal of brain activity." (...)
Brain Scans Reveal Video Gamers' Secrets
health.yahoo.com 21.1.2010
Researchers found that certain regions of the brain are larger in young people who do a better job of playing a specially designed video game.
In other words, all those people who devote their days to their Wiis and XBoxes may be packing some cerebral heat, at least when it comes to the sheer size of what's inside their skulls.
The findings "can help us understand how individual differences contribute to cognitive differences and how we can enhance brain function by increasing the volume of these regions," said study co-author Arthur F. Kramer, a professor of neuroscience and psychology at the University of Illinois at Urbana-Champaign. (...)
Nærmer seg løsning på schizofrenigåta
nrk.no 14.1.2010
Norsk professor vekker internasjonal oppsikt med ny teori om hørselshallusinasjoner. (...)
Kenneth Hugdahl er professor i biologisk psykologi ved Haukeland sykehus i Bergen, og har jobba med Schizofreni i mange år. Ved å ta utgangspunkt i hvordan vi oppfatter språk har Hugdahl kommet fram til at hallusinasjonene må oppstå i språksenteret.
Språksenteret til friske personer aktiveres når de hører en lyd utenfra. Hos schizofrene vil derimot språksenteret aktiveres uten ekstern lyd, nervecellene er opptatt med stemmer innenfra. (...)
Cocaine changes how genes work in brain
reuters.com 11.1.2010
CHICAGO (Reuters) - Prolonged exposure to cocaine can cause permanent changes in the way genes are switched on and off in the brain, a finding that may lead to more effective treatments for many kinds of addiction, U.S. researchers said on Thursday. (...)
This study helps explain how that occurs, Volkow said, and may even lead to new ways of overcoming addiction.
In the study, Maze and colleagues showed these effects could be reversed by increasing the activity of gene 9A.
"When they do that, they completely reverse the effects of chronic cocaine use," Volkow said.
She said this mechanism is likely not confined to cocaine addiction, and could lead to a new area of addiction research for other drugs, alcohol and even nicotine addition. (...)
Where Did the Time Go? Do Not Ask the Brain (Hvor ble tiden av? Ikke spør hjernen)
nytimes.com 4.1.2010
That most alarming New Year’s morning question — “Uh-oh, what did I do last night?” — can seem benign compared with those that may come later, like “Uh, what exactly did I do with the last year?” (...)
“I think for many people, we think about our goals, and if nothing much has happened with those then suddenly it seems like it was just yesterday that we set them,” said Gal Zauberman, an associate professor of marketing at the Wharton School of Business.
Yet the sensation of passing time can be very different, Dr. Zauberman said, “depending on what you think about, and how.”
In fact, scientists are not sure how the brain tracks time. One theory holds that it has a cluster of cells specialized to count off intervals of time; another that a wide array of neural processes act as an internal clock.
Either way, studies find, this biological pacemaker has a poor grasp of longer intervals. Time does seem to slow to a trickle during an empty afternoon and race when the brain is engrossed in challenging work. Stimulants, including caffeine, tend to make people feel as if time is passing faster; complex jobs, like doing taxes, can seem to drag on longer than they actually do.
And emotional events — a breakup, a promotion, a transformative trip abroad — tend to be perceived as more recent than they actually are, by months or even years.
In short, some psychologists say, the findings support the philosopher Martin Heidegger’s observation that time “persists merely as a consequence of the events taking place in it.” (...)
Skjønnhet er… 36 prosent
forskning.no 29.12.2009
Hva er hemmeligheten bak kvinnelig skjønnhet? Tallene 36 og 46 er funnet. (...)
Nå var målet å finne om det er et optimalt forhold mellom øyne, munn og ansikt. Forskerne fant at de ideelle målene er at avstanden mellom øyne og munn skal være 36 prosent av ansiktets lengde og at avstanden mellom øynene skal være 46 prosent av ansiktets bredde. (...)
(Anm: New “golden” ratios for facial beauty. Vision Research 2009 (6 November).)
Teen Marijuana Use Might Have Lasting Effects on Mood, Anxiety (Ungdommer som bruker marihuana kan få varige påvirkninger av sinnsstemning, angst)
health.com 23.12.2009
WEDNESDAY, Dec. 23 (HealthDay News) — Marijuana use among teens may trigger neurological changes in the developing brain that lead to increased anxiety and stress levels that could persist into adulthood, new animal research suggests.
Selv om resultatene kun stammer fra arbeid utført på unge og voksne laboratorierotter — ennå ikke gjentatt på mennesker— tyder arbeidet på visse problematiske endringer av nivåene av nøkkelkjemikaler i hjernen, dvs. serotonin og norepineprin, som kan vedvare lenge etter at bruken av marihuana opphører. "Her var målet bare å , forstå de underliggende nevrologiske mekanismer bak de spesifikke fenomen på depresjon og angst observert i tidligere studier blant ungdommer klinisk eksponert for cannabis,” forklarte studieforfatter dr. Gabriella Gobbi, en forsker innen psykiatri på Research Institute ved McGill University Health Centre i Montreal. (...) (Although the finding stems solely from work conducted with adolescent and adult lab rats — not yet replicated among humans — the work suggests that certain troublesome changes in levels of the key brain chemicals serotonin and norepinephrine may linger long after marijuana use ceases. “Here, the goal was simply to understand the neurological mechanism that could be underlying the specific phenomenon of depression and anxiety observed in previous studies among adolescents chronically exposed to cannabis,” explained study author Dr. Gabriella Gobbi, a psychiatric researcher at the Research Institute of the McGill University Health Centre in Montreal.)
Chromosome protection scoops Nobel
Nature 2009;461:706-707
Three US scientists have won the Nobel Prize in Physiology or Medicine for discovering the structure of molecular caps called telomeres and working out how they protect chromosomes from degradation. Their discoveries in cell biology during the 1980s and 1990s opened new avenues of work, in ageing and in cancer research, which are still highly active today. (...)
Sollyset styrer vårt biologiske urverk
aftenposten.no 15.12.2009
Hvor raskt tikker dine klokker? Kanskje bør du trene senere på dagen, ta medisinen midt på natten. Forskning viser at den biologiske klokken er mer individuell og styrer livet strengere enn vi har ant.
Øynene våre kan mer enn å se. Indirekte bidrar de til å samordne hver eneste celle i hele kroppen – fra fordøyelse til hjerterytme. For øynene fungerer også som en lysmåler, som fanger opp lyssignaler og sender dem som elektriske impulser gjennom et eget nettverk inn i hypothalamus.
Her inne, like over punktet hvor synsnervene krysser hverandre, sitter den: Nucleus suprachiasmaticus – superklokken som ved hjelp av sollyset samordner all aktivitet i hver eneste kroppscelle. (...)
New Hope for Brain, Spinal Cord Injuries
health.usnews.com 11.12.2009
FRIDAY, Dec. 11 (HealthDay News) -- Deleting a gene that suppresses natural growth factors enables regeneration of injured nerve fibers (axons) in mice, a new study shows.
The finding may lead to new treatments for people with brain and spinal cord injuries.
Researchers at Children's Hospital Boston deleted the gene SOCS3 -- an inhibitor of a growth pathway called mTOR -- in the retinal ganglion cells of mice. These cells are in the optic nerve, which carries signals from the eyes to the brain. (...)
Nobelpris for mitotisk klokke
Leder
Tidsskr Nor Legeforen 2009; 129:2470 (3.12.2009)
Historien bak årets nobelpris er gammel, men langt fra ferdigskrevet. Oppdagelsen av telomerprinsippet har endret vår forståelse av mitosekontroll, stamceller og kreftutvikling og kan åpne for nye terapeutiske strategier
Nobelprisen i fysiologi eller medisin for 2009 er tildelt Elizabeth H. Blackburn, Carol W. Greider og Jack W. Szostak for «oppdagelsen av hvordan kromosomene er beskyttet av telomerer og enzymet telomerase». Allerede i 1930-årene la cytogentikere merke til at kromosomer tenderte til å hefte seg sammen og nedbrytes hvis endestykkene manglet. Hermann Muller (nobelpris 1946) og Barbara McClintock (nobelpris 1983) konkluderte derfor at kromosomendene spiller en avgjørende rolle for kromosomets stabilitet (1). (...)
Når basale nyvinninger skal overføres til medisinsk nytte, er som kjent fallhøyden proporsjonal med det antatte potensialet. Mye taler likevel for at årets nobelpris ikke blir den siste som tilfaller telomerrelatert forskning. (...)
Spinal cord injury receives new hope from stem cell research
brainandspinalcord.org 2.12.2009
Spinal cord injury receives new hope from stem cell research
Researchers at Northwestern University’s Institute for Cell Engineering are concentrating on progress with Bone Morphogenetic Proteins as a means of making a major breakthrough in recovery for victims of spinal cord injuries. As Northwestern’s research experts continue to learn about these complex proteins, they are discovering more and more ways in which they are beneficial in repairing spinal cords after traumatic accidents and injuries. (...)
Forskarna skapar datormodell av minneslös mans hjärna
dagensmedicin.se 3.12.2009
En av medicinhistoriens mest berömda hjärnor dissekeras just nu i USA. Alla som vill kan följa undersökningen via nätet.
Följ under-sökningen online:
Henry Molaison från Hartford, USA, hjärnopererades 1953 efter att ha lidit av svåra kramper under hela sin uppväxt. Kramperna upphörde efter ingreppet, men samtidigt försvann hans förmåga att forma nya minnen.
– Han älskade att konversera. På 15 minuter kunde han berätta samma historia tre gånger, med samma ord och satsmelodi, utan att minnas att han just hade berättat den, säger hjärnforskaren Suzanne Corkin från Massachussetts Institute of Technology till New York Times. (...)
(Anm: The Brain Observatory – In Memory of HM. thebrainobservatory.ucsd.edu).)
Bipolar Disorder May Be Tied to Body Clock (Bipolar lidelse kan være knyttet til kroppens indre ur)
health.usnews.com 27.11.2009
FRIDAY, Nov. 27 (HealthDay News) -- New research suggests that an internal body clock that goes on the fritz could be a factor in the development of bipolar disorder in children.
The finding results from the examination of the genetic makeup of 152 children with bipolar disorder, which can make people susceptible to major mood swings, and 140 children without the disorder. They linked variations in a gene known as RORB to the kids with bipolar disorder. (...)
Genet, som er hovedsakelig uttrykt i øyet, pinealkjertel og hjerne, gjør at det antas å være knyttet til kroppens døgnrytme. (The gene, which is mainly expressed in the eye, pineal gland and brain, is thought to be tied to the body's circadian rhythm.)
Fanget 23 år i «koma» - var bevisst hele tida
dagbladet.no 23.11.2009
Legene mente mannen lå i koma. Etter 23 år viste det seg at han hadde vært ved bevissthet hele tida. (...)
46-åringens skjebne ble nylig kjent via en vitenskapelig avhandling ført i pennen av hans redningsmann, nevrologen Steven Laureys.
Avhandlingen ble først omtalt av tyske Spiegel Online.
Legen ved universitetssykehuset i Liège vil nå bruke Houbens eksempel overfor kolleger rundt om i verden.
Han mener Houben ikke er enestående i sitt slag, og hevder det trolig finnes flere slike tilfeller. (...)
(Anm: Mirakelhistorien om Rom Houben var bløff. (dagbladet.no 22.2.2010).)
Vil løse schizofrenigåten
tv2nyhetene.no 12.11.2009
Norsk hjerneforsker får tildelt 20 millioner av EUs forskningsråd.
En av Norges fremste hjerneforskere, professor Kenneth Hugdahl ved Haukeland universitetssykehus, får tildelt 20 millioner kroner over en periode på fem år fra EU for å forske på schizofreni.
– Drømmen er helt enkelt å forklare et av de store, merkelige tingene ved det menneskelige sinnet. Hvordan i all verden kan det komme seg at vi mener at vi hører ting som vi til og med kommuniserer med «individer» som faktisk ikke eksisterer, sier Hugdahl til TV 2 Nyhetene. (...)
Gene Therapy for Fatal Brain Disorder 'Just the Beginning'
news.yahoo.com 5.11.2009
THURSDAY, Nov. 5 (HealthDay News) -- The reported success of gene therapy in treating two children with adrenoleukodystrophy (ALD) brings hope to patients with the potentially crippling and fatal brain disorder and their families, says a nonprofit group that supports ALD research. (...)
Träning av hjärnan skärper minnet på sikt
medfak.umu.se 4.11.2009
Träning av hjärnan ger bestående förbättringar av förmågan att lösa både tränade och ibland även otränade uppgifter, skriver Erika Dahlin i den avhandling hon försvarar vid Umeå universitet den 13 november.
En obesvarad fråga sedan mer än 100 år är varför vi efter träning ibland blir bättre också på otränade uppgifter. Ingen har tidigare utgått från hjärnaktivering för att studera detta närmare, och i avhandlingen används magnetresonansteknik (fMRI, funktionell hjärnavbildning) för att undersöka vilka områden och system i hjärnan som är inblandade vid arbete med både tränade och otränade uppgifter. Med ett datorbaserat träningsprogram för uppdatering av vad vi håller i minnet för stunden studerades prestationen hos unga (20-30 år) och äldre (mer än 65 år) personer före och efter träning. (...)
Toppfolkenes hjerner
ukeavisenledelse.no 2.11.2009
Hjernene til de beste topplederne reagerer annerledes enn andre folks hjerner.
Det viser forskning gjort av førsteamanuensis Harald Harung ved Høgskolen i Oslo hvor aktiviteten i topplederes hjerner er sammenlignet hjerneaktivitet hos medarbeidere i lavere stilling.
- Undersøkelsen viser at topplederne hadde bedre samarbeid mellom ulike områder i hjernen, sier Harung til Dagens Næringsliv. (...)
Funnene viser at det hos lederne var en sterkere samstemthet mellom de områdene i hjernen som kobler sammen persepsjon, planlegging, strategi og handling enn det var hos kontrollgruppen. (...)
De så også at topplederne var flinkere enn andre til å mobilisere når de skulle mobilisere og slappe av når de burde slappe av. Et annet fellestrekk ved topplederne, var at de var bedre i stand til å ignorere uvesentligheter og forstyrrelser underveis i testen. (...)
Åderförkalkning. En av våra vanligaste folksjukdomar
sr.se 16.10.2009
Hjärt och kärlsjukdomar är några av de vanligaste dödsorsakerna i Sverige. Sjukdomarna kopplas ofta till vår moderna livsstil med för mycket mat och för lite motion. Men trots att så många drabbas så finns det mycket som vi inte vet om orsakerna till åderförkalkning som är första steget i sjukdomsförloppet.
Åderförkalkning. En av våra vanligaste folksjukdomar
Kanske är det inflammation i kroppen som orsakar åderförkalkning och inte tvärtom. I dagens Vetandets värld träffar vi professorn i medicin Johan Frostegård som hoppas att inflammationsteorin ska kunna resultera i ett vaccin mot en av våra absolut vanligaste folksjukdomar.
– Mycket tyder på att åderförkalkning inte alls är en naturlig del av vårt åldrande, säger han. (...)
Autoimmune cognition disorders often mistaken for neurodegenerative disease
clpmag.com 14.10.2009 (Reuters Health)
(...)
On behalf of his colleagues, Dr. Eoin P. Flanagan from the Mayo Clinic in Rochester, Minnesota, described 72 patients in whom an autoimmune cause for cognitive impairment or dementia was suspected.
Clues to the etiology included subacute onset in 72%, fluctuating symptoms in 65%, thyroid autoantibodies in 57%, neural-specific antibody in 41%, neuroimaging atypical for a neurodegenerative process in 25%, elevated cerebral spinal fluid levels of protein (> 100 mg/dL) or pleocytosis in 25%, and newly detected seizure disorder in 17%.
Sixty-four percent of patients had other abnormal neurological findings such as tremor or other parkinsonian symptoms, peripheral neuropathy, myoclonus, ataxia, dysphagia, apraxia, and hyperreflexia. (...)
With immunosuppressive therapy, 64% of subjects improved, as documented by clinical and radiological measures. When maintenance immunotherapy was reduced, 57% of treated patients relapsed.
"We believe that many patients are misdiagnosed," Dr. Flanagan noted. "Dementia at a young age should immediately raise suspicions." (...)
How Nonsense Sharpens the Intellect
nytimes.com 5.10.2009
In addition to assorted bad breaks and pleasant surprises, opportunities and insults, life serves up the occasional pink unicorn. The three-dollar bill; the nun with a beard; the sentence, to borrow from the Lewis Carroll poem, that gyres and gimbles in the wabe. (...)
At best, the feeling is disorienting. At worst, it’s creepy.
Now a study suggests that, paradoxically, this same sensation may prime the brain to sense patterns it would otherwise miss — in mathematical equations, in language, in the world at large. (...)
Autopsies shine light on dementia
starbulletin.com 4.10.2009
Subjects of decade-long studies continue to aid researchers in death (...)
The Honolulu-Asia Aging Study was expanded over the years with research and significant discoveries on diseases associated with aging. The program has received more than $72 million in federal funds since the 1960s. (...)
Fewer than six studies worldwide are looking intensely at dementia and Alzheimer's disease. The Honolulu study has been a leader with some findings "revolutionizing the way people think about these diseases," White said.
"We have been able to correct a huge number of important misunderstandings related to the causes of dementia," he said, adding that "loss of cognition late in life is a whole lot more complicated than we used to think it was."
He said the researchers found processes contributing to dementia that have been attributed incorrectly to Alzheimer's disease.
For example, they have found changes in tiny arteries of the brain produced by a vascular disease, molecular changes often seen in Parkinson's disease in the cerebral cortex, which has a role in memory, and loss of neurons in the area of the brain associated with memory. (...)
The study eventually will provide information on nearly 1,000 men with any signs of dementia measured during their lives, such as trouble walking, talking or interacting socially, White said. "This gives us a chance to follow it right into the structures, cells and molecules in the brain to find out what is going on. It is an incredible opportunity." (...)
En av tre blev dement efter återkommande stroke
dagensmedicin.se 24.9.2009
Multipla stroke medför högre risk för insjuknande i demens än kardiovaskulära riskfaktorer, enligt forskarna bakom en ny metaanalys.
Den nya analysen, som publiceras i dag, torsdag, på tidskriften Lancet Neurologys hemsida, baseras på 22 sjukhusstudier och åtta populationsstudier. Undersökningarna är utförda mellan 1950 och 2009.
Av analysen framgår att demens var cirka tre gånger vanligare efter återkommande stroke som efter ny stroke. Efter en första stroke utvecklade cirka 10 procent av patienterna demens de första månaderna. Efter en återkommande stroke hade mer än 30 procent av patienterna demens. (...)
- Alkohol svekker immunforsvaret
vg.no 21.9.2009
(VG Nett) Ny forskning viser at kroppen er mer utsatt for sykdom et helt døgn etter alkolinntak.
Alkoholinntak gjør oss mer utsatt for bakteriesmitte. En amerikansk studie viser at alkoholen hemmer viktige «voktere» i kroppen slik at de mister evnen til å gi beskjed om at en bakterie er på vei.
Uten denne beskjeden får ikke kroppen satt i gang sine forsvarsmekanismer, og man blir mer utsatt for halsbetennelse eller andre bakterieinfeksjoner, skriver forskning.no. (...)
Older Brains May Not Be So Small After All
healthfinder.gov 21.9.2009
Decrease in gray matter isn't a given, researchers find.
MONDAY, Sept. 21 (HealthDay News) -- Scientists have assumed that people's brains shrink as they age, but researchers now suspect that's not the case.
A study in the September issue of Neuropsychology examines long-term Dutch research into aging brains, which used neurological tests and MRI scans to measure parts of the brain. (...)
Ankle Circulation Could Warn of Future Strokes
healthfinder.gov 28.8.2009
Quick test may detect peripheral artery disease, research shows.
FRIDAY, Aug. 28 (HealthDay News) -- A simple test of blood circulation in the ankle could help doctors identify patients at high risk of suffering another stroke, researchers say.
The test compares blood flow in the ankle to that in the arm. A significant difference between the two readings could suggest that a patient suffers from peripheral artery disease, caused by fatty plaque buildup in the arteries of the extremities, the researchers explained in a news release from the American Heart Association. (...)
In the study, which appeared online Aug. 27 in Stroke, researchers sought to figure out how the condition affects patients. (...)
Mild Head Trauma Can Cause Brain Dysfunction (Mild hodeskade kan forårsake hjernedysfunksjon)
medpagetoday.com 26.8.2009
Mild traumatic brain injury can cause acute impairment in executive function, which is detectable by diffusion tensor imaging, data from a small clinical study showed.
Clusters of fractional anisotropy in lower frontal white matter predicted worse performance on tests of executive function.
Several clusters also demonstrated increased mean diffusivity compared with brain images from a control group, Michael Lipton, MD, PhD, of Albert Einstein College of Medicine in Bronx, N.Y., and colleagues reported online in Radiology. (...)
Dårlig konsentrasjon:
Multitasking sløver hjernen
nrk.no 26.8.2009
Sitter du typisk med musikk på øret mens du oppdaterer Facebook-profilen og ser på tv? Da er du antakelig dårlig til å oppfatte flere ting på en gang. (...)
All forskning viser at vi ikke kan ta imot for mye informasjon og inntrykk på en gang når vi skal lære noe nytt, som NRK Puls fortalte i fjor. (...)
Nå viser det seg også at de som ofte forsøker å dele oppmerksomheten mellom flere informasjonskilder, faktisk er dårligere til å oppfatte flere ting samtidig enn andre, skriver Forskning.no. (...)
Relationship Found Between Autism and Autoimmune Disorders
Psychiatr News 2009;44(16):25 (August 21) (American Psychiatric Association)
Growing evidence points to a link between the immune system and brain development, but whether this link can be traced to genetics remains a mystery.
A family history of rheumatoid arthritis, type 1 diabetes mellitus, or celiac disease is associated with a higher risk of developing autism spectrum disorders in children, a recent study found.
A group of Danish and U.S. researchers collected medical data on all children born in Denmark to Danish mothers between 1993 and 2004 and matched these children with their parents' and siblings' hospital records. Any diagnoses of autoimmune diseases identified before the children were diagnosed with an autism spectrum disorder were analyzed for possible correlations with the children's risk for such a disorder. (...)
- Vi går i ring når vi går oss vill - og tror det ikke etterpå
vg.no 21.8.2009
(VG Nett) Forskning viser at filmklisjeen om at vi går i ring når vi har gått oss vill i naturen faktisk stemmer.
En ny studie publisert i Current Biology ville teste hvordan vi klarer oss når vi går ute i fremmede omgivelser.
Noen testpersoner måtte gå i flere timer i Sahara-ørkenen, mens andre gikk på langtur i et skogsområde i Tyskland med mål om å gå mest mulig rett i en tilfeldig retning. Alle fikk kartlagt bevegelsene ved hjelp av GPS-teknologi. (...)
Han tror at grunnen sil sirkelgangen er at hjernen får mange signaler fra forskjellige deler av kroppen når man går, som ofte ikke er helt riktige.
- Alle disse signalene har små feil og disse feilene vil av og til samle seg og peke deg i en bestemt retning, sier han. (...)
Blodprov visar hjärnskada
sr.se 18.8.2009
Hjärnskador hos amatörboxare kan nu mätas även i blodprov. Sönderfallet av nervceller verkar fortsätta, även om boxarna hållit sig borta från ringen under två månader. Det visar en ny studie från Sahlgrenska akademin.
Resultaten är ännu ett bevis för att upprepade slag mot huvudet skadar hjärnan. I studien analyserades blodprover från 44 turkiska amatörboxare efter två månaders uppehåll från boxning.
Forskarna analyserade flera proteiner som kännetecknar hjärnskada och såg att ett av dem var förhöjt hos amatörboxarna jämfört med en frisk kontrollgrupp. (...)
Lesions Linked to Risk of Old-Age Memory Problems
medpagetoday.com 11.8.2009
White matter hyperintensities -- brain lesions detected on MRI -- may predict the risk of memory problems in older individuals, a cross-sectional study has found.
Individuals 65 and older who had these lesions were nearly twice as likely as others to have a form of mild cognitive impairment characterized by memory deficits (OR 1.8, 95% CI 1.0 to 3.2), according to Jose Luchsinger, MD, MPH, of Columbia University, and colleagues.
In addition, those who had the most infarcts had an increased risk of nonamnestic mild cognitive impairment, which is characterized by cognitive deficits that don't involve memory (OR 2.7, 95% CI 1.5 to 4.8), the researchers reported in the Aug. 11 issue of Neurology. (...)
(Anm: Subclinical cerebrovascular disease in mild cognitive impairment. NEUROLOGY 2009;73:450-456 (August).)
Alkohol holder hjernen frisk
dinside.no 22.7.2009
Moderate mengder kan beskytte mot demens. (...)
Personer med noe svekkede kognitive evner som hadde et høyt alkoholforbruk hadde dobbelt så stor risiko for å bli demente.
- Siden alle har ulike syke- og familiehistorier er ikke alkoholinntak nødvendigvis hensiktsmessig for alle som vil senke risikoen for å bli demente, understreker dr. Sink. (...)
Brain Quickly Detects Happiness in Others (Hjernen oppdager raskt andres lykke)
healthfinder.gov 6.7.2009
Study finds people perceive positive expressions more accurately than sad ones.
MONDAY, July 6 (HealthDay News) -- When it comes to picking up emotional signals from others, the brain responds to happiness faster than sadness, a new study has found. (...)
The findings are reported in the third issue this year of the journal Laterality: Asymmetries of Body, Brain and Cognition. (...)
(Anm: Laterality: Asymmetries of Body, Brain and Cognition.)
Case Report
Citalopram-Induced Bleeding Due to Severe Thrombocytopenia
Psychosomatics 50:297-298, May-June
BACKGROUND: In case reports and observational studies, serotonin reuptake-inhibitors (SSRIs) have been linked to an increased risk of bleeding, possibly due to platelet dysfunction as a consequence of serotonin-uptake blockade into platelets. OBJECTIVE: The authors propose that bleeding as a result of SSRI use may also be caused by other mechanisms. (...)
CONCLUSION: As this case report shows, drug-induced immune thrombocytopenia may present another possible mechanism for bleeding in SSRI-treated patients. (...)
Brain Imaging Study Sheds Light on Fibromyalgia (Studie som involverer hjerneskanning kaster lys over fibromyalgi)
healthfinder.gov 19.6.2009
Link found between gray matter and dopamine levels in patients.
FRIDAY, June 19 (HealthDay News) -- Changes in the levels of the neurotransmitter dopamine may explain brain gray matter reductions experienced by patients with fibromyalgia, a new study suggests.
Previous research found an association between fibromyalgia and reductions in gray matter, but the cause wasn't known, the researchers wrote. (...)
The new study, published in the June issue of the Journal of Pain, also found that fibromyalgia patients showed a strong correlation of dopamine metabolism levels and gray matter density in areas of the brain where dopamine is known to control neurological activity.
This association between dopamine levels and gray matter density offer new information about a possible mechanism behind some of the brain abnormalities seen in fibromyalgia patients, the researchers concluded. (...)
Standard IQ Test May Undervalue People With Autism (Standard IQ-tester kan undervurdere mennesker med autisme)
healthfinder.gov 19.6.2009
Study shows they could solve problems faster than non-autistics on a different test.
FRIDAY, June 19 (HealthDay News) -- The most commonly used test to measure intelligence is underestimating the intellectual potential of autistic people, new research suggests.
People with autism often struggle with the verbal portions of the Wechsler Adult Intelligence Scale, the test most often used to measure IQ, researchers said.
But when given another test of abstract reasoning abilities, the Raven's Standard Progressive Matrices, autistic people not only had scores equal to those of their non-autistic counterparts, but they answered the questions, on average, as much as 42 percent more quickly.
On the Raven's test, autistic participants scored, on average, 30 percentage points higher than would have been predicted by their scores on the Wechsler scale, according to the study, in the June issue of Human Brain Mapping.
Also, MRIs done during the testing showed that autistic people had more activity in different areas of their brains than those without autism. (...)
Hjernespinn
aftenposten.no 12.6.2009
Internett, SMS, TV og e-post, helst alt sammen samtidig.
Vi «multitasker» for å spare tid. Og rekker snart ingenting.
«MULTITASKING» er vår tids mantra. Fortell sjefen at du ikke fikser å ha flere baller i luften på en gang, og se hvor begeistret hun blir. (...)
Kommunikasjon mellom nerveceller i netthinnen
Tidsskr Nor Legeforen 2009; 129:1200 (11.6.2009)
Studier av levende nerveceller fra rotteøyne gir ny innsikt i hvordan ulike typer nerveceller i netthinnen kommuniserer og genererer synsinntrykk i dunkel belysning.
Synssansen er en av våre mest komplekse sanser og den spiller en avgjørende rolle for vår interaksjon med miljøet rundt oss. Svein Harald Mørkve har undersøkt hvordan cellene i netthinnen kommuniserer. (...)
Vi har undersøkt signaloverføringen som gir synsinntrykk når belysningen er dunkel, og har blant annet sett spesielt på hvordan glutamattransportere på bestemte presynaptiske nevroner fungerer. Vi har vist at glutamat som brukes for å sende signaler over den synaptiske spalten påvirker membranpotensialet til avsendercellen og inhiberer denne. Glutamat frisatt i synapsen «renner» over og påvirker også signaloverføringen mellom naboceller. Dette er helt ny kunnskap som har vakt en viss oppsikt, sier Mørkve. (...)
Herb May Offer Hope for Autoimmune Diseases (Urt kan gi håp for autoimmune sykdommer)
healthfinder.gov 4.6.2009
In lab and mice studies, compound halts disease without crimping immune system.
THURSDAY, June 4 (HealthDay News) -- A compound derived from hydrangea root, an herb used in traditional Chinese medicine, halted the progression of an autoimmune disorder in laboratory mice and human cells, new research shows.
What makes the compound, halofuginone, so promising, the researchers said, is that it slowed progression of the disease without suppressing normal immune system functioning.
A major drawback to current treatments for autoimmune disease is increased risk for infections because of suppressed immune system functioning, according to the study, which appears in the June 5 issue of Science.
"This is really the first description of a small molecule that interferes with autoimmune pathology but is not a general immune suppressant," said the study's lead study author, Mark Sundrud, from the cellular and molecular medicine program and the Immune Disease Institute at Children's Hospital Boston. (...)
Commonly Used Medications May Produce Cognitive Impairment in Older Adults
communications.medicine.iu.edu 1.6.2009
INDIANAPOLIS -- Many drugs commonly prescribed to older adults for a variety of common medical conditions including allergies, hypertension, asthma, and cardiovascular disease appear to negatively affect the aging brain causing immediate but possibly reversible cognitive impairment, including delirium, in older adults according to a clinical review now available online in the Journal of Clinical Interventions in Aging, a peer reviewed, open access publication.
Drugs, such as diphenhydramine, which have an anticholinergic effect, are important medical therapies available by prescription and also are sold over the counter under various brand names such as Benadryl®, Dramamine®, Excederin PM®, Nytol®, Sominex®, Tylenol PM®, and Unisom®. Older adults most commonly use drugs with anticholinergic effects as sleep aids.
While it is known that these medications do have an effect on the brain and in the case of sleeping pills, are prescribed to act on the brain, the study authors suggest the amount of cognitive impairment caused by the drugs in older adults is not well recognized. (...)
Study Links Cancerous Tumors With Depression (Studie linker kreftsvulster med depresjon)
healthfinder.gov 20.5.2009
Research with rats finds biological tie between growths and mood changes.
WEDNESDAY, May 20 (HealthDay News) -- Doctors have long known that people with cancer often suffer from depression.
A new study in rats has found that the cause of the depression may be the properties of the tumor itself, rather than emotional distress over the diagnosis or side effects from chemotherapy.
The study is the first to identify a biological link between tumors and negative mood changes, according to the researchers, who published their study in the May 18 issue of the Proceedings of the National Academy of Sciences.
About 15 percent to 20 percent of patients diagnosed with cancer experience depression, according to the U.S. National Cancer Institute.
Researchers put about 100 rats through a series of exercises commonly used by researchers testing antidepressants in animal models. Some of the rats had cancerous tumors.
The investigators found that the rats with tumors were less motivated to escape when submitted to a swimming test, a condition that is similar to depression in humans. The rats with tumors also were less eager to drink sugar water, a substance that healthy rats usually find irresistible.
"In this case, examining behavioral responses to tumors in non-human animals is particularly useful, because the rats have no awareness of the disease, and thus their behavioral changes were likely the result of purely biological factors," said senior study author Brian Prendergast, associate professor of psychology at the University of Chicago. (...)
APA: Depression Linked to Obesity Mainly in Women (APA (American Psychiatric Association): Depresjon linket til fedme hovedsakelig hos kvinner)
medpagetoday.com 20.5.2009
SAN FRANCISCO, May 20 -- Depression may be more closely associated with obesity in women than in men, researchers found.
Overall, obese women were 3.9 times more likely to be depressed than normal weight women (P=0.04), Tuan-Anh Nguyen, M.D., M.P.H., of Maricopa Integrated Health System in Phoenix, Ariz., reported here at the American Psychiatric Association meeting.
But obese men were only 2.54 times as likely to be depressed as their normal weight counterparts, a difference that was not significant (P=0.84), according to an analysis of data from the National Health and Nutrition Examination Survey (NHANES).
The researchers defined obesity as a Body Mass Index (BMI) of 30 to 39 and morbid obesity as a BMI of 40 or higher. (...)
Fear Response May Stem From Protein in Brain
healthfinder.gov 16.5.2009
Discovery in mice could someday help control anxiety, experts say.
FRIDAY, May 15 (HealthDay News) -- For almost 7 million Americans, fear and anxiety isn't something associated with heights, a job interview or getting lost in a strange city.
It's a chronic state of worry and tension that affects twice as many women as men and grinds away for no apparent reason, slowly eroding their quality of life.
But a new study published in the current issue of Cell has made a discovery that offers sufferers hope for a more relaxed life. (...)
Cocaine Spurs Long-Term Change in Brain Chemistry (Kokain forårsaker kjemiske langtidsendringer i hjernen)
healthfinder.gov 14.5.2009
Study in mice finds drug alters gene activity, points to new methods for treatment.
THURSDAY, May 14 (HealthDay News) Many remember those fried-egg "this is your brain on drugs" public service announcements. Now, a new study offers insight into how addictive drugs such as cocaine "cook" the brain.
"The study's findings enable us to glimpse for the first time exactly how cocaine modifies the activity of genes in regions of the brain that that mediate reward," explained Nora Volkow, the director of the U.S. National Institute on Drug Abuse, the organization that supported the study. "These genes represent promising new targets for the development of medications to treat cocaine addiction," she said. (...)
Drug Addiction as a Brain Disorder or Disease—Reply (Substansavhengighet som en sykdom - tilsvar)
JAMA. 2009;301(18):1881-1882. (May 13)
(...) In the text we used the terms disease and disorder interchangeably. This usage is consistent with how these terms are used in psychiatry and related fields.3 Drug addiction is considered a brain disorder or disease since it results from the functional disruption of brain circuits involved with reward (manifested as decreased sensitivity to nondrug reinforcers and enhanced incentive value for drug reinforcers), memory or learning (manifested as automatic reflexive responses on exposure to drug-conditioned stimuli and as hard-to-break habits), and inhibitory control (manifested as poor control, impulsivity, and compulsive drug taking).4 There is also evidence of disruption in circuits involved with stress control (manifested as anxiety associated with protracted drug withdrawal).5 Drug addiction is considered a chronic disorder or disease of the brain because the abnormalities in these neuronal circuits are long lasting and some of these persist months after drug discontinuation.6 (...)
Få en skarp hjerne ved at lave ingenting
business.dk 29.4.2009
Høje krav belaster, og det er efterhånden blevet »in« at sige, at man har travlt på jobbet. Travlheden kan give stress og depressioner, og derfor arbejder Eve Bengta Lorenzen med at få folk til at sætte tempoet ned.
Forskning viser, at meditation kan ses i hjernen allerede efter otte uger. Hjernen forandrer sig og fungerer mere effektivt. (...)
De to hjernehalvdele
Forskning fra University of Massachusett og Harvard Medical School viser, at mindfulness styrker evnen til at være til stede. Efter otte ugers meditation bliver hjernen mere velfungerende, fortæller Eve Bengta Lorenzen.
De videnskabelige fakta om mindfulness er, at samarbejdet mellem de to hjernehalvdele bliver bedre og, at aktiviteten i højre pandelap, der styrer følelser som irritation, vrede, angst og depression, forskydes over i venstre pandelap, der styrer følelser som entusiasme, nysgerrighed, glæde og lykke. I sidste ende bliver man et gladere og mere kreativt menneske.
Eve Bengta Lorenzen har selv været leder i omkring ti år, blandt andet for et miljøuddannelsescenter. Hun var leder, fordi hun brændte for et projekt, og det var vigtigt for hende, at projekterne kørte. (...)
Skiftet dialekt etter hjerneoperasjon
nettavisen.no 28.4.2009
Har du hørt den om engelskmannen som snakket med irsk aksent da han våknet etter hjernekirurgi? (...)
Spesialister knytter tilfellet opp mot en medisinsk fenomen kalt Fremmed Aksent Syndrom (AKS), som kan påvirke pasientens kontroll over lepper, tunge og stemmebånd i ekstremt sjeldne nevrologiske tilfeller. Syndromet ble først oppdaget i Norge i 1941 da en ung kvinne som ble skadd under et bombeangrep våknet opp igjen og snakket med tysk aksent. (...)
Brain imaging skewed
Published online 27 April 2009 | Nature | doi:10.1038/4581087a
Double dipping of data magnifies errors in functional MRI scans.
Nearly half of the neuroimaging studies published in prestige journals in 2008 contain unintentionally biased data that could distort their scientific conclusions, according to scientists at the National Institute of Mental Health in Bethesda, Maryland.
Experts in the field contacted by Nature have been taken aback by the extent of the methodological errors getting through the supposedly strict peer-review systems of the journals in question.
Nikolaus Kriegeskorte, Chris Baker and their colleagues analysed 134 functional magnetic resonance imaging (fMRI) studies published last year in five top journals — Nature, Science, Nature Neuroscience, Neuron and The Journal of Neuroscience. The survey, published in Nature Neuroscience on 26 April (N. Kriegeskorte, W. K. Simmons, P. S. F. Bellgowan and C. I. Baker Nature Neurosci. 12, 535–540; 2009), found that 57 of these papers included at least one so-called 'non-independent selective analysis'; another 20 may also have done so, but did not provide enough information to confirm suspicions. (...)
Exercise Reduces Leakage through the Blood Brain Barrier (Trening reduserer lekasje igjennom blod-hjernebarrieren)
ivanhoe.com 22.4.2009
Ivanhoe Newswire) -- A recent study suggests physical exercise may strengthen the blood- brain barrier, limiting harmful materials from entering the brain.
In the study, 3-month-old male mice represented men in their 20s. A group of 25 mice were held five weeks with exercise wheels that were used regularly and given the human equivalent of one gram of methamphetamine. These mice were compared with 25 mice that were also injected with the meth but did not have access to exercise wheels.
After analyzing the results, researchers found the meth caused higher body temperatures as well as agitated and increased physical activity in all the mice. However, the non-active mice experienced increased oxidative stress, affecting the permeability of the blood-brain barrier. The active mice experienced no such results.
Results show how regular exercise may have yet another benefit -- delaying the formation of neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Both diseases are connected with leakage through the blood-brain barrier.
SOURCE: Presented at the Experimental Biology meeting in New Orleans, April 22, 2009 (...)
(Anm: blod-hjernebarrieren; en tynn hinne eller membran mellom blodårene i hjernen og hjernevevet, hindrer mange stoffer i å komme fra blodet og inn i hjernen. Kilde: Store norske leksikon.)
Avslører hjernens motorveier
uib.se 1.4.2009
Hvis hjernens sentre er byer, så er nervebanene mellom dem motorveier. Ny avbildningsteknikk kartlegger rutenettet.
Mellom hjernecellene, som kalles ”den grå massen”, finnes et område som kalles "den hvite massen". Dette er nervefibrer som leder kommunikasjonen mellom de ulike områdene av hjernen.
– Frem til nå har nervenettet blitt kalt ”den hvite massen”, fordi det fremstår nettopp som en hvit ensartet flate ved vanlig klinisk MR-skanning, sier professor Derek Jones, fra Cardiff University Brain Research Imaging Center. (...)
Study: Poor kids' stress affects brain
seattletimes.nwsource.com 7.4.2009
Children raised in poverty suffer many ill effects: They often have health problems and tend to struggle in school, which can create a cycle of poverty across generations. (...)
Research Links Poor Kids' Stress, Brain Impairment (Forskning linker fattige barns stress til hjernesvekkelse)
washingtonpost.com 6.4.2009
Children raised in poverty suffer many ill effects: They often have health problems and tend to struggle in school, which can create a cycle of poverty across generations.
Now, research is providing what could be crucial clues to explain how childhood poverty translates into dimmer chances of success: Chronic stress from growing up poor appears to have a direct impact on the brain, leaving children with impairment in at least one key area -- working memory. (...)
Abuse and the Brain (Mishandling og hjernen)
JAMA. 2009;301(13):1329. (April 1)
Early childhood abuse might exert lifelong effects by altering a person's DNA and reducing levels of glucocorticoid receptors in the brain, which are important for responding to stress, Canadian scientists have found (McGowan PO et al. Nat Neurosci. 2009;12[3]:342-348).
The investigators examined brain tissue from 24 men who had committed suicide, half of whom had a history of childhood abuse, and from 12 men who had not been abused and died suddenly from other causes. Men with a history of abuse had lower levels of glucocorticoid receptors than did men who had not been abused or had not committed suicide. In addition, in those who had been abused, a snippet of "promoter" DNA that normally facilitates the production of glucocorticoid receptors had been silenced by the attachment of a methyl group.
The researchers noted the work confirms their previous findings from animal studies showing that adult rats that had been raised by neglectful mothers had similarly altered DNA, fewer glucocorticoid receptors, and an amplified physiological response to stress compared with attentively mothered rats. (...)
Afflictions of the Brain, Cured or Not
nytimes.com 31.3.2009
There are two sides to every disease story — a lot more if you count the patient and the doctor, the patient’s relatives and the doctor’s relatives, the nurses, the therapists and the insurer. What a shame that the only time we ever get to hear all of them is in court. Otherwise, it is pretty much all monologue out there in the literature of health lost and regained, with all the usual problems of perspective and turf. (...)
No music is allowed in Dr. Black’s operating room. It requires superhuman patience and concentration to peer into a microscope for hours, peeling apart gauzy layers of tissue to remove all these invaders. He likens the work to that of a cat burglar, his aim to get in and out of the brain without leaving a trace. One false move and the patient may never see, hear, smell again — or may never wake up at all. (...)
Brain Waves Can Predict Mistakes
Ivanhoe.com 30.3.2009
(Ivanhoe Newswire) -- Just before you make a mistake, your brain actually gives off a warning sign. This discovery could lead to the development of devices that alert air traffic controllers that their attention is flagging, researchers said.
A team of scientists at the University of California, Davis, worked with the Donders Institute in the Netherlands to study students' brain activity during an attention-demanding test. Using a non-invasive technique called magnetoencephalography (MEG), which is similar to but more sensitive than an EEG -- the technique commonly used in hospitals to detect seizures -- the researchers recorded the students' brain waves during a monotonous test. (...)
Brain differences mark those with depression risk
news.yahoo.com 23.3.2009
CHICAGO (Reuters) – People who have a high family risk of developing depression had less brain matter on the right side of their brains on par with losses seen in Alzheimer's disease, U.S. researchers said on Monday.
Brain scans showed a 28-percent thinning in the right cortex -- the outer layer of the brain -- in people who had a family history of depression compared with people who did not.
"The difference was so great that at first we almost didn't believe it. But we checked and re-checked all of our data, and we looked for all possible alternative explanations, and still the difference was there," said Dr. Bradley Peterson of Columbia University Medical Center and the New York State Psychiatric Institute.
His study appears in the Proceedings of the National Academy of Sciences. (...)
Brain Death (Hjernedød)
JAMA. 2009;301(11):1192. (March 18)
A person dies when brain function ceases, the heart stops beating, and breathing and blood circulation cease. Because life-support techniques have become so advanced, it is possible that even in the face of fatal injury or unrecoverable illness, the heart can be kept beating with medication, and respiration (breathing) can be artificially performed with a ventilator. The concept of brain death developed in response to these advanced medical techniques that can maintain some bodily functions. Brain death, as understood in US law and medical practice, occurs when there is no function of the entire brain. The brainstem is the area of the brain that controls breathing and circulation and therefore controls essential life functions. When the brain, including the brainstem, has ceased to function, the individual is truly dead by medical and legal standards. Thus, brain death is real death. The March 18, 2009, issue of JAMA includes an article about brain death. This Patient Page is based on one published in the May 14, 2008, issue of JAMA. (...)
(Anm: Consciousness, Coma, and Brain Death--2009. JAMA 2009;301 1172-1174.)
Diabetes øker risikoen for Alzheimer
vg.no 17.3.2009
(VG Nett) Ny forskning viser en illevarslende forbindelse: Diabetes øker risikoen for Alzheimers sykdom.
Det er velkjent at diabetes kan være skadelig for hjertet, nyrer, øyne og bein, men nå har altså forskere funnet at sykdommen også kan ha konsekvenser for kognitive funskjoner hos eldre.
Leger har lenge hatt mistanke om at diabetes ødelegger blodårene som forsyner hjernen med blod. Nå tyder mye på at det er verre enn som så. Det ser ut som at ødeleggelsen starter før man oppdager at man har diabetes, men når kroppen gradvis mister evnen til å regulere blodsukkeret, skriver nyhetsbyrået Associated Press (AP).
I virkeligheten er skillet diffust mellom det ekspertene kaller vaskulær demens og den klassisk Alzheimers sykdom.
Yaakov Stern, Alzheimer-spesialist ved Colombia University Medical Senter, sier til AP at akkurat nå er det ikke mye man kan gjøre med Alzheimer. Dersom man imidlertid kunne kontrollere de vaskulære tilstandene (de bittesmå blodproppene), kunne man også sinke utviklingen av sykdommen. (...)
- Type 2 diabetes oppstår som et resultat av insulinresistens når kroppen gradvis mister sensitiviteten til dette hormonet som er essensielt for å omdanne blodsukker til energi. En lignende effekt i hjernen kan delvis forklare forbindelsen til demens, konkluderer dr. Suzanne Craft fra Veterans Affairs Puget Sound Health Care System, kriver i en artikkel publisert i Archives of Nevrology. (...)
Dette er et menneske fra innsiden
vg.no 13.3.2009
HENRETTET FANGE: Bildet over er et tverrsnitt av liket til den henrettede fangen Joseph Paul Jernigan. Dette bildet er hentet fra mageregionen. Norske forskere bruker datasettet fra «The Visual Human Project» i ny banebrytende medisinsk forskning.
(VG Nett) Bildet over er en av 1871 en-millimetertykke skiver av en henrettet amerikansk fange. Norske forskere er i full gang med å bruke dette materialet i ny, banebrytende forskning. (...)
Forny din egen hjerne
nrk.no 12.3.2009
Ny forskning viser at kroppen vår kan kan lage nye hjerneceller hele livet - selv om du er 100 år!
Hjernen vår har adskillig større evne til å reparere seg selv enn det vi trodde tidligere. Ja den kan også produsere nye hjerneceller, såkalte nevroner, hele livet uavhengig av hvor gamle vi er, hevder Fred Gage hjerneforsker ved Salk Institute i USA. (...)
Vi har mange ulike typer hjerneceller, og det er nevronene det stadig kan lages nye av. Nevronene er svært kompliserte nerveceller som med elektriske og kjemiske impulser bringer beskjeder til og fra hjernen.
De har en viktig oppgave, og det er mange av dem, vi har mer enn 15 millarder nevroner i hjernen.
Nevronene fødes i den delen av hjernen som kalles hippocampus. Dette området i storhjernen spiller antagelig også en rolle for læring og hukommelse.
Når et nytt nevroner fødes har det utspring i det som kalles stamceller.
tamcellene har den fantastiske egenskapen at de kan produsere nye, friske nevroner hele menneskelivet igjennom.
Men skal denne prosessen fungere også når vi blir gamle, er det noen forutsetninger som må være tilstede. (...)
Overtid kan svekke hjernen din
aftenposten.no 26.2.2009
Folk som jobber mye overtid, skårer dårligere på intellektuelle ferdighetstester enn folk med normal arbeidstid, ifølge ny forskning.
2214 statsansatte briter deltar i studien som har pågått siden 1997. Resultatene er offentliggjort i American Journal of Epidemiology.
Slik ble de testet
Forsøkspersonenes mentale prestasjoner ble målt ved hjelp av fem ulike tester: Blant annet ble de presentert for ulike ord og bedt om å peke ut synonymer fra en liste. Mens stoppeklokken gikk skulle de regne opp ord som begynner på en bestemt bokstav. Det ble også gjennomført klassiske IQ-tester - deltagerne ble for eksempel bedt om å komplettere visse tallrekker.
Målingene ble gjort i to omganger: Først i 1997-1999 og deretter i 2002-2004. (...)
- Nettsamfunn kan «barnliggjøre» hjernen
aftenposten.no 26.2.2009
Oxford-professor advarer mot nettsamfunn som Facebook og Twitter. - Kan påvirke hjernen til barn og unge negativt , mener hun.
Den anerkjente britiske nevrologen og professoren ved universitetet i Oxford, baronesse Susan Greenfield, er alvorlig bekymret for hvordan bruken av sosiale nettverkssider som Facebook, Twitter og Bebo kan påvirke hjernen til barn og unge, skriver The Guardian på sine nettsider.
Greenfield frykter bruken kan gjøre den oppvoksende generasjon mer selvsentrerte og mindre empatiske. Konsentrasjonsevnen står også i fare, mener hun, og hevder det er en risiko for at nettsamfunn kan forårsake en infantlilisering eller barnliggjøring av hjernen og hvordan den fungerer. (...)
En helt spesiell hjerne
aftenposten.no 23.2.2009
Professor Inge Morild studerer arven etter Anna Elisabeth Westerlund, Norges mest berømte synske kvinne. (...)
Thrill-Seekers' Brains May Be Wired Differently
healthfinder.gov 19.2.2009
Region that affects addictive behavior is linked to risk-taking, too, study finds. (...)
When high-sensation seekers viewed the emotional or arousing images, their brains showed increased activity in the region called the insula. Previous studies have found this area is active during addictive behaviors, such as craving cigarettes. When the low-sensation seekers saw the emotional or arousing images, activity increased in their brains' frontal cortex, which controls emotions.
The findings, published in the February issue of Psychological Science, could indicate the way by which sensation-seeking can result in negative behaviors, such as substance abuse and antisocial conduct, the researchers said.
"Individuals high in sensation-seeking not only are strongly activated by exciting, thrilling and potentially dangerous activities but also may be less likely than other people to inhibit or appropriately regulate that activation," the researchers concluded. (...)
Avund syns i hjärnan (Misunnelse synes i hjernen)
sr.se 19.2.2009
Avundsjuka och skadeglädje syns i hjärnan. För första gången har ett forskarlag sett att den här sortens rätt så abstrakta sociala upplevelser faktiskt orsakar en fysisk förändring i hjärnan.
Att avundsjuka och skadeglädje är känslor som har stor påverkan på våra liv förstår man inte minst av att avund räknas som en av de sju dödsynderna, och att det finns ett ordspråk som säger att skadeglädje är den enda sanna glädjen. (...)
Ensamhet mäts i hjärnan
sr.se 16.2.2009
Att känna sig isolerad och ensam ger mätbara skillnader i hur hjärna fungerar, enligt ny forskning som presenterats vid forskarmötet AAAS i Chicago.
Forskare vid university of Chicago använde en magnetkamera för att studera hjärnorna hos grupper av människor som först fick svara på frågor om hur ensamma de kände sig.
Resultaten visade att delar av hjärnan som är förknippade med belöning aktiverades mindre hos ensamma när de såg bilder av människor i trivsamma situationer. De ensamma hade med andra ord svårare att dela andra människors glädje.
John Cacioppo vid university of Chicago, som ledde studien, säger att hälsoeffekterna av ensamhet kan vara allvarliga i längden.
– Folk som känner sig ensamma och isolerade har högre blodtryck och drabbas värre av alzheimer. De sover också sämre och vaknar oftare under natten, säger John Cacioppo.(...)
Hjerneskade hos premature målt ved 14 års alder
Tidsskr Nor Legeforen 2009; 129:275 (12.2.2009)
Norske forskere har påvist endringer i nervefibersubstansen i hjernen hos ungdommer som var sterkt premature ved føds
Hvilket kjønn er hjernen din?
nrk.no 29.1.2009
Finn ut om hjernen din er mannlig eller kvinnelig.
Denne testen kan gi innblikk i om hjernen din heller i en maskulin eller feminin retning. Det er ingen fasitsvar på spørsmålene – resultatet gir bare en pekepinn om det sannsynlige nivået mannlige hormoner som hjernen din mottok 6-8 uker etter at du ble unnfanget. Dette vil avspeile seg i preferanser, atferd, væremåte, valg og legning. (...)
Concussion's Effects May Linger for Decades
healthfinder.gov 28.1.2009
Attention, memory, physical processes affected even 30 years after injury, study finds.
(SOURCE: Oxford University Press, news release, Jan. 27, 2009)
WEDNESDAY, Jan. 28 (HealthDay News) -- Athletes who suffer a concussion can experience a decline in their mental and physical processes more than 30 years later, according to a Canadian study that's the first to identify these kinds of long-term effects.
The researchers examined 40 healthy, former university-level athletes between the ages of 50 and 60. Of those, 19 had suffered a concussion more than 30 years ago, and 21 had no history of concussion.
Compared to those who were concussion-free, the participants who'd been concussed only once or twice in their early adulthood showed declines in attention and memory, as well as a slowing of some types of movement.
The study was published online Jan. 28 in the journal Brain. (...)
'Time Stamp' in Brain Cells Encodes Memories
healthfinder.gov 28.1.2009
New neurons allow events to be recalled from a certain period, study suggests.
(SOURCE: Salk Institute for Biological Studies, news release, Jan. 28, 2009)
WEDNESDAY, Jan. 28 (HealthDay News) -- The thousands of new brain cells generated each day in an adult's brain carry a code that "time stamps" memories, according to researchers at the Salk Institute for Biological Studies in California.
"By labeling contemporary events as similar, new neurons allow us to recall events from a certain period," study leader Fred H. Gage, a professor in the Laboratory for Genetics, said in an institute news release. (...)
The study was published in the Jan. 29 issue of Neuron. (...)
Syv sekunders afbrydelser gør dig dummere
business.dk 20.1.2009
Forskning i hjernen viser, at vi er mest kreative, når vi undgår forstyrrelser. Derfor at det er en dårlig ide at arbejde i storrum, hvor der ofte er afbrydelser.
Din intelligensformåen bliver reduceret med op til 20 procent i løbet af en dag med mange afbrydelser. Når du sidder bøjet over en opgave, kan en afbrydelse på få sekunder ødelægge dit flow, og det tager op mod 15-20 minutter at vende tilbage til samme arbejdsniveau, som inden du blev afbrudt. (...)
Hjernedoping fremmer forståelsen
videnskab.dk 14.1.2009
Det er ikke kun sportsfolk, der doper sig. Almindelige mennesker, der hverken dyrker bjergbestigning eller landevejscykling, søger i stigende grad at forbedre livskvalitet og ydeevne ved hjælp af livsstilsmedicin (...)
(Anm: Løgn, pisspreik eller sannhet? (mintankesmie.no).)
Doper bier spinnville med kokain
vg.no 6.1.2009
Målet er å lete etter måte å forhindre kokain i å virke på menneskehjernen. (...)
- Forskere har påvist ekte kjærlighet
vg.no 5.1.2009
(VG Nett) Amerikanske forskere mener de har funnet bevis for at ekte kjærlighet eksisterer. Metode: Hjernescanning.
Ifølge Sunday Times er det et team fra Stony Brook University i New York som har scannet hjernene til par som har vært sammen i over 20 år. (...)
Likevel er det kanskje ikke bare godt nytt. Forskerne fant nemlig bare dette hos ett av ti par som hadde vært sammen i 20 år eller mer. (...)
Forandringer i hjernen hos schizofrene
Tidsskr Nor Legeforen 2009; 129:4 (1.1.2009)
Pasienter med schizofreni har tynnere hjernebark og mindre volum av hjernevev i panne- og tinninglappene enn friske. Endringene er sykdomsrelatert.
Schizofreni rammer om lag 1 % av befolkningen. Sykdommen debuterer oftest i begynnelsen av 20-årene, og menn er yngre enn kvinner ved debut. Antipsykotiske medikamenter kan lindre symptomer, men de fleste pasientene trenger langvarig behandling. I avhandlingen Characterization of brain morphology in patients with schizophrenia påviser Ragnar Nesvåg endringer i hjernemorfologi hos pasienter med schizofreni.
Resultatene bygger på klinisk intervju og MR-undersøkelser av pasienter og kontrollpersoner. (...)
Hvordan vet du at du er på kanten?
dagbladet.no 20.12.2008
Norske forskere har funnet svaret. (...)
Før nå. Forskere ved NTNU i Trondheim har funnet en helt egen celletype for akkurat det å merke at kanten er nær. Og svaret ligger dypt inne i hjernen.
GRENSEN ER NÅDD for rotta som løper rundt i en stor kasse, og straks knitrer det i signaler fra de nyoppdagede grensecellene. (...)
Forskere ved Kavli Institute for Systems Neuroscience på NTNU har oppdaget en ny type celler som har en enkelt livsoppgave:
Å varsle fra om kanter, hindre og vegger. (...)
Fant 2.000 år gammel hjerne
aftenposten.no 13.12.2008
Arkeologer I England har funnet det som antagelig er den eldste hjernen i landet.
Hjernevevet, som ble funnet inni en hodeskalle, stammer fra jernalderen, og er minst 2.000 år gammelt, ifølge en artikkel på CNN.com.
Restene av hjernen kom for dagen under en utgravning ved York-universitet I Nord-England. (...)
Hjernearbeiderne
aftenposten.no 4.12.2008
I hodet til rotte nummer 12975 gjør forskerne i Trondheim så oppsiktsvekkende funn at verden har tvilt på om de kan stemme. (...)
Løsningen for å få nok punkter var rett og slett å utvide rotteboksene. Der gnagerne før hadde tasset rundt på én ganger én meter, fikk de nå større plass å boltre seg på. Snart strente de nedover en 18 meter lang løpebane. Og omsider var resultatene tydelige: Ved hjelp av stedcellene lager hjernen et kart over det området den befinner seg i, hver celle dekker et visst område i kartet, som kan brukes overalt, også i helt ukjent terreng. (...)
Funnet av gittercellene, og dermed stedsansen, var en langsom aha-opplevelse for de fem forskerne som jobbet med det: May-Britt, Edvard og tre av studentene deres. Internasjonalt vakte funnet oppstandelse. Hjernens funksjoner er fortsatt lite utforsket, og et så konkret funn som et indre kart, er ikke dagligdags. Så oppsiktsvekkende var det, at mange tvilte på om det kunne stemme. (...)
Myter om hukommelse
nrk.no 21.11.2008
Er det sant at barn husker bedre enn eldre, eller at vi bare bruker ti prosent av hjernen vår? Vi gir deg mytene og sannheten om vår hukommelse. (...)
Gammel og glemsk, sier vi ofte, men det medfører ikke alltid riktighet. Selv om mange i 40-50-årsalderen påstår at de husker dårligere enn før, er nok årsaken heller en travel og stresset hverdag, enn at det er aldren som tynger.
Forskning viser at for de fleste av oss er hukommelsen intakt til vi nærmer oss 70. Og fordi vi har tilegnet oss mange erfaringer og mye kunnskap gjennom et langt liv, husker de fleste svært godt enda lengre, selv om evnen til å lære nye ting blir gradvis redusert. (...)
Hjernetrim i søk og surf
forskning.no 18.10.2008
Datakyndige middelaldrende og eldre folk kan dra nytte av å bryne sine små grå på internett. (...)
Funnene viser at nettsøk kan stimulere hjernefunksjonen, og kanskje forbedre den.
Det ferske forskningsarbeidet skal publiseres i en kommende utgave av tidsskriftet American Journal of Geriatric Psychiatry.
Studien skal være den første i sitt slag til å vurdere betydningen slike aktiviteter har på hjernens yteevne.
(Anm: American Journal of Geriatric Psychiatry.)
Internettsurfing øker hjerneaktiviteten
dagbladet.no 15.10.2008
Særlig for dem over femti.
NETTET ER BRA: Ifølge ny forskning stimuleres hjernen når man surfer på internett. Dette skal være svært bra - særlig for de som har passert femti. (...)
- En enkel dagligdags oppgave, som å søke på nettet, ser ut til å forbedre hjernesirkulasjonen hos eldre. Dette demonstrerer hvor sensitiv hjernen er, og at man kan tilegne seg kunnskap selv når man er eldre, sier professor Smith til BBC.
Vi forsker som aldri før
aftenposten.no 4.10.2008
– Bemerkelsesverdig i internasjonal sammenheng
Norsk forskning øker kraftig til tross for at forskningsmiljøet i flere år har klaget over mangelen på penger. (...)
Stjerneeksempel. Hjerneforsker Ole Petter Ottersen er et stjerneeksempel på den norske suksessen. Lederen ved Senter for molekylærbiologi og nevrovitenskap ved Universitetet i Oslo demonstrerer et avansert elektronmikroskop for Aftenposten. Bilder av hjernens vannkanaler – som er 10
milliarddels meter brede – blir synlige. Ottersens forskning på disse kanalene kan gi bedre behandling av slagpasienter. Nå får mannen som har publisert
en strøm av artikler i prestisjetunge forskningstidsskrifter, Anders Jahres medisinske pris, som blir regnet som Nordens mest prestisjefulle innen forskning. (...)
Verdenstoppen. I den internasjonale forskningsbasen ISI finnes 14 nordmenn.
– Det er slutt på den tiden da forskeren kunne sitte alene på et kontor. Man er helt avhengig av internasjonale forskningsnettverk for å få tilgang til kompetanse og teknologi. For å få tilgang til slike nettverk må man være synlig i tunge forskningstidsskrifter mener han.
Ottersen og hans team har påvist at hjernen inneholder vannkanaler som sørger for riktig vannbalanse. Når hjernen kommer i ubalanse, for eksempel
ved slag, kan man få en opphopning av vann i hjernen. Det kan bli et stort problem fordi kraniet ikke utvider seg, noe som kan føre til store senskader
og død.
– Behandlingen av vannansamling i hjernen er i prinsippet den samme som for 70–80 år siden, men vi jobber nå for å finne medisiner som kan motvirke en slik opphopning av vann, forklarer Ottersen.
Han får overrakt Anders Jahres pris førstkommende fredag i Oslo, med kong Harald til stede. (...)
Market Mess? Blame Your Brain
forbes.com 24.9.2008
What caused the meltdown on Wall Street? Greed. Lax regulation. Panic.
And maybe the very biological makeup of investors' brains. (...)
One reason: Investors fear losing more than they look forward to winning. According to a 2007 paper, researchers used MRI scans to watch the brains of people as they decided whether or not to take gambles with a 50/50 risk. Gains caused brains to light up in areas that released dopamine (the chemical boosted by Zoloft and Prozac); losses caused those same areas to decrease. Researchers could predict what people would do based on the size of the increases.
Dread, the anticipation of a loss that is expected to happen, is another powerful force. Emory's Berns has shown that people differ in how they respond to expected pain. He gave electric shocks to people in an MRI machine, and then gave them the option of either getting an intense shock immediately or a less intense shock later. People whose brains started lighting up in areas associated with pain beforehand were more likely to decide to get the pain over with. They also would have sold stock. (...)
Recovery Tough for Brain Injury Patients (Tilfriskning vanskelig for hjerneskadede pasienter)
ivanhoe.com 15.9.2008
(Ivanhoe Newswire) -- Forskning har vist at noen mennesker synes å bli helt friske etter en hjerneskade, fordi de skårer like bra som friske på standard kognitive tester. Men resultatet fra en ny studie viser at dette kanskje ikke er riktig. Undersøkelsen avslører at pasientens hjerne kan fullføre oppgaven like bra, men at de er nødt til å jobbe hardere enn det friske mennesker gjør. (...) (-- Research has shown that some people appear to make a full recovery after a brain injury because they score as well as healthy individuals on standard cognitive tests. But a new study finds that may not be the case. The research reveals that the patient’s brain may complete the task as well, but it has to work harder than the healthy individual’s brain.)
Ikke send hjernen til topps
aftenposten.no 28.9.2008
Faren for varig hjerneskade er større enn tidligere antatt.
Gjennomsnittshjernen trives best null meter over havet, skriver forsker Pål Johan Karlsen.
Hjernene krympet. Faren for varig hjerneskade er større enn tidligere antatt - også hos klatrere som ikke kjenner symptomer på høydesyke. Hjerneceller dør av oksygenmangel eller fordi de går i stykker i press mot skallen. Både noviser og erfarne tar kostbare sjanser.
Den spanske nevrologen Nicholas Fayed og kolleger skannet hjernen til 35 klatrere - 12 profesjonelle og 23 amatører. De hadde nettopp returnert fra svimlende høyder, de største fjelltoppene i fire verdensdeler. En gruppe hadde forsøkt seg på Mount Everest (8848 m), en annen på Aconcagua i Andesfjellene (6962 m), en tredje på Kilimanjaro (5895 m), og en fjerde Mont Blanc i Alpene (4810 m). Ingen brukte oksygenmaske. De ble sammenlignet med 20 kontrollpersoner.
Gjennomsnittsalderen var 34 år. Over halvparten hadde målbare skader.
Væskerom inngår i nervesystemets dreneringssystem og hjelper blodårene
å skifte ut væske. Kilimanjaro er den enkleste toppen å bestige - bare
en av syv klatrere hadde unormalt store væskeansamlinger. Av de syv
som hadde besteget det lavere, men brattere europeiske fjellet, hadde to
fått utvidede væskerom. Utvidede væskerom i hjernen er noe man normalt
bare ser hos eldre personer. Utvidelsen betyr at noe har forsvunnet
- og det er hjerneceller. (...)
Doper hjernen
nrk.no 11.9.2008
Legemidler som får deg til å tenke kjappere, huske bedre og prestere på høyt nivå uten å bli sliten, finnes allerede på markedet. Men er det juks å dope hjernen?
USA raser debatten om medikamentene som kan gjøre deg smartere, såkalt hjernedop. Det er medisin som i utgangspunktet er tiltenkt pasienter med alzheimer, ADHD, og andre lidelser som har sitt utgangspunkt i kjemiske ubalanser i hjernen. (...)
Problemet er at alle medaljer også har en bakside. Og det er ingen spøk å tukle med hjernen, til det er kunnskapen vår alt for begrensa, og risikoen for høy.
- Medisinen virker ikke bare på de ønskede nervecellene, men også andre nerveceller som ligner. Dette kan i verstefall gjøre oss forvirret og endre hjernen, sier Jan Gunnar Bjaalie som er professor og leder ved International Neuroinformatics Coordinating Facility (INCF). (...)
Brain Injury Patients Cope by Using More of Their Brains
medpagetoday.com 9.9.2008
TORONTO, Sept. 9 -- Patients who recover fully from head trauma may have to use more of their brains than they did before the injury to perform the same mental tasks, researchers found. (...)
Vitamin B12 Key to Aging Brain
healthfinder.gov 8.9.2008
Deficiency led to more brain shrinkage, study shows. (...)
MONDAY, Sept. 8 (HealthDay News) -- Older individuals with low levels of vitamin B12 seem to be at increased risk of having brain atrophy or shrinkage, new research suggests.
Brain atrophy is associated with Alzheimer's disease and impaired cognitive function.
Although the study, published in the Sept. 8 issue of Neurology, can't confirm that lower levels of B12 actually cause brain atrophy, they do suggest that "we ought to be more aware of our B12 status, especially people who are vulnerable to B12 deficiency [elderly, vegetarians, pregnant and lactating women, infants], and take steps to maintain it by eating a balanced and varied diet," said study co-author Anna Vogiatzoglou, a registered dietician and doctoral candidate in the department of physiology, anatomy and genetics at the University of Oxford, in England.
"It's worth looking at B12 levels. It's a simple blood test," affirmed Dr. Shari Midoneck, an internist at the Iris Cantor Women's Health Center in New York City. "It doesn't hurt to take B12."
Good sources of the vitamin include meat, fish, milk and fortified cereals. (...)
Trim hjernen
konsulentguiden.no 20.8.2008
- I USA er hjernetrim blitt ny business. (...)
Militæret vil lese tankene dine
dagensit.no 16.8.2008
Bruker 20 millioner på å analysere hjerneaktivitet. (...)
Empathy Is 'Hard-Wired' in Children's Brains
healthfinder.gov 16.7.2008
Scans show young naturally prone to relate to pain in others, study says.
WEDNESDAY, July 16 (HealthDay News) -- Empathy comes naturally to children, a new report shows.
Using functional MRI scans on normal kids aged 7 to 12, researchers found the parts of the children's brains that were activated when shown pictures of people in pain, according to findings published in the current issue of Neuropsychologia. (...)
Unge arbeidstakere skader seg oftest på jobb
dagbladet.no 24.6.2008
Fordi hjernene deres ikke er ferdig utviklet.
HJERNENS UTVIKLING: Bildet viser modningen av hjernebarken som i hovedtrekk starter i bakhodeområdet med synsfunksjonene, deretter kroppsbeherskelse og videre fremover til frontallappene. (...)
Appelsinens hemmelighet
aftenposten.no 20.6.2008 (Aftenposten Amag)
Lukter påvirker oss.
Appelsinduft gjør
for eksempel fanger
mindre agressive.
MANGE MULIGHETER
Selv en lukt nesen ikke merker,
kan berolige, oppkvikke
- eller få oss til å kjøpe ting. (...)
VARETEKTSFANGENE i Rotterdam merker
ingenting. De føler seg bare litt lettere
til sinns og spør sjeldnere etter beroligende
medisiner. I tre måneder nå
har de 66 cellene i fengselet duftet svakt
av appelsin. Lukten kommer fra en liten
plastflaske med appelsinolje som pumpes
ut i lufteanlegget. 24 timer i døgnet,
hver dag hele uken. Seks liter flytende
appelsinduft går det med i løpet av en
måned.
- Vi merker at fangene er mindre
aggressive. De slåss mindre og bruker
mindre beroligende medisiner og antidepressiva,
forteller Herma Hesteer som
leder sosialtjenesten i Rotterdam-politiet. Tidligere luktet cellene ofte av svette, urin
og skirt. Nå er den vonde lukten borte
- erstattet av en god, som attpåtil påvirker
humøret til fangene positivt, lærlukt,
for at det skal lukte det folk flest
forbinder med lukten av ny bil. (...)
(Anm: Søvn (mintankesmie.no).)
The Science of Sarcasm (Not That You Care)
nytimes.com 3.6.2008
There was nothing very interesting in Katherine P. Rankin’s study of sarcasm — at least, nothing worth your important time. All she did was use an M.R.I. to find the place in the brain where the ability to detect sarcasm resides. But then, you probably already knew it was in the right parahippocampal gyrus. (...)
Håp for de med lav IQ
dn.no 16.6.2008
Sliter du med IQ-testen? Det er ikke lenger trøstesløst. (...)
Plastisk
- Mange forskere har ikke trodd det er mulig å forbedre intelligensen. Våre funn viser klart at dette ikke stemmer. Hjernen vår er mer plastisk enn vi kanskje tror, sier Susanne M. Jaeggi ved University of Michigan i Ann Arbor, USA.
Forskerne tenkte seg at siden krystallisert intelligens er avhengig av langtidsminnet, så må flytende intelligens være knyttet til korttidsminnet, eller arbeidsminnet som det heter. (...)
Homofiles hjerner er annerledes
nrk.no 16.6.2008
Deler av hjernen til en lesbisk kvinne likner på den til en heterofil mann, viser ny forskning fra Karolinska Institutet. (...)
Brainpower May Lie in Complexity of Synapses
nytimes.com 10.6.2008
Evolution’s recipe for making a brain more complex has long seemed simple enough. Just increase the number of nerve cells, or neurons, and the interconnections between them. A human brain, for instance, is three times the volume of a chimpanzee’s. (...)
Dr. Grant looked at the interconnections between neurons, known as synapses, which until now have been regarded as a standard feature of neurons.
But in fact the synapses get considerably more complex going up the evolutionary scale, Dr. Grant and colleagues reported online Sunday in Nature Neuroscience. In worms and flies, the synapses mediate simple forms of learning, but in higher animals they are built from a much richer array of protein components and conduct complex learning and pattern recognition, Dr. Grant said. (...)
Technology and Drugs are Changing Brain Function
redorbit.com 11.5.2008
An Oxford University neuroscientist has warned that human identity faces an unprecedented crisis, brought about by damage caused by various electronic gadgets and pharmaceuticals that blur the line between our bodies and the outside world.
Writing in Britain’s Daily Mail, neuroscientist Susan Greenfield, Oxford University Alzheimer’s researcher and author of the book “ID: The Quest For Identity In The 21st Century”, says modern technology, including violent video games, multichannel television and the Internet, is altering the way our brains work.
“The human brain….is under threat from the outside world,” Greenfield wrote.
“The crisis could reshape how we interact with each other, alter what makes us happy, and modify our capacity for reaching our full potential as individuals.” (...)
In other words, the brain’s development is impacted in significant ways by our surrounding environment, from early childhood through early adulthood, and even beyond. (...)
Our modern brains are having to simultaneously adapt to new technological advancements and other intrusions as well, such as prescription and illegal drugs like Prozac, Ritalin, cannabis and heroin.
“Electronic devices and pharmaceutical drugs all have an impact on the micro- cellular structure and complex biochemistry of our brains. And that, in turn, affects our personality, our behavior and our characteristics. In short, the modern world could well be altering our human identity.” Greenfield said. (...)
“I am optimistic and excited by what future research will reveal into the workings of the human brain, and the extraordinary process by which it is translated into a uniquely individual mind. But I'm also concerned that we seem to be so oblivious to the dangers that are already upon us.” (...)
Visste du dette om hjernen?
vg.no 9.5.2008
Derfor får du låter på hjernen
Hvorfor er det alltid de mest irriterende låtene som henger seg opp i hjernen, og er det virkelig slik at blinde hører bedre? (...)
How Big Is Your Brain?
foxcentraloregon.com 30.4.2008
Size May Protect You from Memory Loss
CHICAGO -- From autopsies, researchers have long known that some people die with sharp minds and perfect memories, but their brains riddled with the plaques and tangles of Alzheimer's disease. New research shows that those people have a larger part of the brain called the hippocampus. (...)
Praise as good as cash to brain: study (Ros like bra som kontant betaling for hjernen: ifølge studie)
reuters.com 24.4.2008
CHICAGO (Reuters) - Paying people a compliment appears to activate the same reward center in the brain as paying them cash, Japanese researchers said on Wednesday.
They said the study offers scientific support for the long-held assumption that people get a psychological boost from having a good reputation. (...)
Hverdagsvalg tapper hjernen
vg.no 23.4.2008
Latte eller cappucino? Stor eller liten? Med eller uten sukker? De små valgene gjør det vanskeligere å fokusere på viktigere ting (...)
'Worry' Spot in Brain Found
healthfinder.gov 11.4.2008
But anxiety could be helpful in long run, researchers note. (...)
FRIDAY, April 11 (HealthDay News) -- Stanford researchers report that worrying about something before it happens might do more than just create knots in your stomach.
They found that people who seemed to have higher levels of "anticipatory worry" -- judged by brain scans of activity in a part of the brain known as the anterior insula -- did better in a financial game, said study author Gregory Samanez-Larkin, a psychology graduate student at Stanford.
If the anterior insula was more active, the subjects had "a higher fidelity when it comes to making economic decisions," said Samanez-Larkin. "They were better at predicting what might happen." These volunteers learned to avoid losses when playing the same game months later, he noted.
"I wouldn't call it intelligence," he said. Instead, "it's a sort of expertise." (...)
The results were published in the April issue of Psychological Science. (...)
Still, expanded knowledge about that particular brain region could lead to better treatments for anxiety and help researchers predict who might do a better job of handling stress, Miranda said.
Samanez-Larkin said the research could also be used to detect people who are most likely to get too many credit cards and fall into debt or fall victim to scams, because they aren't adept at processing financial information. "You could identify people who are susceptible to things like this and try to help them," he said. (...)
Ulik språkforståelse
nrk.no 7.3.2008
For gutter og jenter er ikke nødvendigvis språk det samme. Ny forskning tyder på at hjernen jobber forskjellig hos kjønnene for å forstå skrift og tale. (...)
Når hjernen jazzer
forskning.no 4.3.2008
Når jazzmusikere improviserer, slukkes aktiviteten i en selvsensurerende del av hjernen, mens avdelingen for selvuttrykk får det travelt. (...)
When Cancer Spreads to the Brain
ivanhoe.com 25.2.2008
MIAMI, Fla. (Ivanhoe Newswire) -- Brain metastasis -- when cancer spreads to the brain from another part of the body -- is the most feared complication of systemic cancer. Metastases accounts for about 40 percent of all brain cancers but no longer comes with the automatic death sentence of the past thanks to advances in radiology.
At the American College of Radiation Oncology’s 18th annual conference in Miami, Fla., John Suh, M.D., from the Cleveland Clinic, discussed the available options for treatment. Of particular interest: is traditional whole brain radiation treatment still a favorable option? (...)
Whole brain radiation can cause alopecia, fatigue, headaches, memory loss and confusion. In a recent study, 11 percent of patients treated with whole brain radiation suffered severe dementia. Given these unfavorable side effects, many doctors feel the loss of the patient’s quality of life makes them look to other treatment options. (...)
- Det siste vi har på plass, er det vi trenger mest
aftenposten.no 21.2.2008
(...) Hver fjerde person som blir skadet i en trafikkulykke er 24 år eller yngre, og 44 ungdommer i alderen 15 til 24 år mistet livet i trafikken i Norge i 2007. (...)
Impulsivitet
Det er frontallappene som kan spille oss et puss før vi er 25 år. Det er i frontallappene hjernen styres og administreres med hensyn til planlegging, gjennomføring og kontroll av hvordan vi oppfører oss.
- Denne delen av hjernen utvikler seg aller senest. Vi tror denne delen er viktig for planlegging, beslutninger og impulsivitet. Det er store individuelle variasjoner, men gjennomsnittlig er ikke denne delen ferdig utviklet før vi er 25 år, sier professor i nevrovitenskap på NTNU, Edvard Moser, til Aftenposten.no. (...)
Verdensledende hjerneforskning i 70 år
apollon.uio.no 8.1.2008
På 1930-tallet begynner historien om det som skulle bli et helt enestående forskningsmiljø i Norge, og som i utlandet omtales som The Oslo School of Neuroanatomy.
En håndfull menn og kvinner har i årenes løp greid å sette Norge på verdenskartet: Ibsen, Munch, Undset, Heyerdahl, Solskjær. Og noen flere. (...)
Avhengig? Hjernen har svaret
aftenposten.no 3.1.2008
En gang i fremtiden trenger ikke avhengige å vente på sin egen erkjennelse. (...)
Rotteforsøk.
Forskningen har allerede fastslått at kjemiske forhold i hjernen kan være medvirkende faktorer ved avhengighet. Undersøkelser av stoffene serotonin, noradrenalin og dopamin viser at disse kan avsløre fellestrekk ved flere former for avhengighet. Professor Kathleen Brady, en avhengighetsforsker ved Medical University i Sør-Carolina, er en av dem som har prøvd å sette dette i sammenheng.
- Det som skjer når en person utvikler et usunt avhengighetsforhold, er at dopaminsystemet får problemer med å holde tilførselen ved like. Hjernen får mindre dopamin. Dette får den konsekvensen at vedkommende kan får problemer med å føle glede og tilfredsstillelse over det som gjør andre glade, uttaler hun til det amerikanske avhengighetsprosjektet, The Addiction Project. (...)
Expert: Teen brain key to understanding criminal behavior
cnn.com 28.12.2007
Latest research shows brain continues to develop to age 25 and beyond
Teen brains lack impulse control, sophisticated reasoning capability
Some advocates say teens should be judged differently in criminal justice system.
Supreme Court in 2005 outlawed death penalty for crimes committed before 18 (...)
Brain Turns to Positive Thoughts When Faced With Death
healthfinder.gov 28.12.2007
Unconscious response points to 'psychological immune system,' study suggests.
FRIDAY, Dec. 28 (HealthDay News) -- When thoughts of death intrude, the human mind isn't paralyzed with negativity or fear. Instead, the brain instinctively moves toward happier notions and images, a new study suggests.
The finding supports the notion that people are stronger, emotionally, when faced with their own or a loved one's death than they may have ever thought possible. (...)
(Anm: Psychological Science. 2007;18(11):984-990 (November 2007).)
Brain Cells More Powerful Than You Think
healthfinder.gov 19.12.2007
Even single neurons have a big impact on behavior, studies show.
WEDNESDAY, Dec. 19 (HealthDay News) -- The human brain constantly sorts through its 1 trillion cells, looking for perhaps only one or a handful of neurons to carry out a particular action, a trio of new studies says.
The research, conducted with rodents and published in the Dec. 20 issue of Nature, could rewrite the textbooks on just how important individual brain cells or cell clusters are to the working mind.
Before these insights, "The thinking was that very large ensembles of neurons [brain cells] had to be activated at some point for the animal to feel or perceive" a stimulus, explained the senior researcher of two of the studies, Karel Svoboda, a group leader at the Howard Hughes Medical Institute in Ashburn, Va. (...)
More information
Learn more about the human brain at The Franklin Institute. (...)
Er du smartere enn apen?
dn.no 9.12.2007
Japanske tester viser at sjimpanser har en fantastisk evne til å huske siffer. Sjekk om du slår apen. (...)
- Ingen hadde forestilt seg at de skulle klare å slå menneskene, sier han til CNN Technology.
Resultatene av de oppsiktsvekkende testene er publisert i forskningstidsskriftet Current Biology. (...)
Sjimpanser slo menneskene
aftenposten.no 3.12.2007
Sjimpanser slo menneskene ned i støvlene i et dataspill som måler hukommelse. (...)
Study: Infants Can Judge Naughty From Nice
cbsnews.com 21.11.2007
Even 6-Month-Old Babies Show Crucial Social Judging Skills Among Playmates (...)
Når hjernen misser grepet
uib.no 13.11.2007
Hjernen kan vise teikn til demens lenge før pasientar merkar symptoma, viser resultat frå nevrobiologisk forsking.
Å ta godt vare på menneske med demens er ei viktig, men dyr og krevjande oppgåve. Etter kvart som befolkninga i vestlege samfunn blir eldre, vil også fleire oppleve å få ein eller annan form for demens. Difor vil det vere viktig å kunne fange opp utvikling av demens så tidleg som råd, slik at ein kan kome i gang med tiltak som kan bremse utviklinga. (...)
Protein avgjør hvor godt du takler motgang
vg.no 25.10.2007
(VG Nett) Et protein i hjernen styrer hvor godt du takler motgang, viser ny forskning. (...)
Nå hevder forskere i en ny studie at det er mengden av proteinet Brain-derived neutrophic factor (BDNF) som styrer hvor godt vi takler påkjenninger, og nivået er merkbart lavere hos personer som ikke takler det så godt. (...)
- Tren og spis sunt
- Både aktivitet og diett kan ha god effekt på produksjon av BDNF og andre funksjoner i hjernen. Det å være i fysisk aktivitet har vist seg å øke BDNF, og stimulering av miljø har også god effekt. Stress over lengre tid kan være med på å redusere mengde BDNF i enkelte deler av hjernen, sier hun, og gir følgende råd:
- Tren, spis sunt og ikke utsett deg for stress over lengre tid. (...)
Minimum telomere length defined for healthy cells
Nature 2007;449:515
Mechanism for chromosome corruption also revealed.
How long have I got left, doctor? For a cell, at least, scientists may be close to an answer. A cell's lifespan depends on the length of its telomeres — the regions of repeating DNA that protect the ends of chromosomes. Every time a cell divides, its telomeres get shorter until they become unstable and cause chromosomes to fuse together. These fusions can make the chromosomes break when cells divide, leading to cell death or triggering genomic rearrangements associated with the early stages of cancer. (...)
Brain's memory capacity less than thought
msnbc.msn.com 14.9.2007
There may be billion of neurons, but function limited by connectivity issues (...)
Lämna din kropp
svd.se 24.8.2007
Vår hjärna är helt beroende av sinnesintryck för att veta var vi är – var vårt jag finns, visar ny forskning.
Så går det tillKlicka här för att se hela grafiken (öppnas i nytt fönster) (...)
Ser seg selv utenfra
forskning.no 24.8.2007
For første gang i historien har forskere framprovosert ut av kroppen-opplevelser under kontrollerte forhold. Dette er av stor interesse for fagfelt fra nevrologi til teologi, og kan få store konsekvenser for virtual reality-teknologi. (...)
En ut av kroppen-opplevelse er en følelse av å forlate sin egen kropp og se seg selv fra utsiden.
Det er en tilstand som for eksempel kan inntreffe når hjernen har problemer (som under epileptiske anfall og slag), eller som følge av narkotikabruk. (...)
Scientists Spot Brain's 'Free Will' Center
healthfinder.gov 23.8.2007
It helps people refrain from actions good and bad, experts say. (...)
Scientists say one part of the brain is responsible for initiating action, while a totally separate area is in charge of not taking that action. (...)
(Anm: The Journal of Neuroscience 2007;27(34):9141-9145 (August 22).)
Nerve cell stretchiness uncovered
bbc.co.uk 17.8.2007
A protein stops nerve cells from breaking, research suggests
US scientists may have discovered why long nerve cells do not break when you move or stretch your limbs.
Experiments in worms showed that when a protein called beta spectrin is missing, nerve cells are brittle and break, leading to paralysis.
The finding may help to explain why people with a condition called spinocerebellar ataxia progressively lose co-ordination and movement.
The University of Utah study is in the Journal of Cell Biology. (...)
Brain Stimulation Rouses Minimally Conscious Man
abcnews.go.com 1.8.2007
Doctors Insert Electrode Rods Into Man's Brain, Breaking Comalike State
For six years, the patient lay silent -- unable to move, eat or speak after suffering a traumatic brain injury from a blow he received to his head during a robbery. (...)
The science behind this stunning recovery was published Wednesday in the journal Nature. (...)
Barokk hjerneforskning
forskning.no 2.8.2007
Det er når musikken tar en pause, at vi virkelig legger merke til den. Ny forskning kaster nytt lys på hvordan hjernene våre fungerer. Særlig når vi hører på barokkmusikk.
Det finnes mange myter om hvordan musikk påvirker oss. For noen måneder siden meldte forskning.no at den såkalte Mozart-effekten er tilbakevist nok en gang.
Men det finnes altså seriøse forskere som ser på hva som skjer med oss når vi hører på musikk. (...)
Forskningsresultatene publiseres i siste utgave av fagtidsskriftet Neuron. (...)
De valgte musikk skrevet av den engelske komponisten William Boyce (1711- 1779).
Kan lære å glemme vonde minner
vg.no 13.7.2007
(VG Nett) Forskere tror de har funnet ut hvordan mennesker med vilje kan manipulere hjernen til å glemme vonde minner. (...)
Brain can quickly warn us of potential errors
msnbc.msn.com 3.7.2007
Mind takes less than a second to prevent repeated mistakes, scientists say (...)
Scientists have long known that mistakes are conducive to learning, suggesting the reason lies in the element of surprise upon finding out we are wrong. But how the brain manages to learn from mistakes and how quickly it does so have been unknowns. (...)
- Déjà vu skyldes feil i hjernen
dagbladet.no 8.6.2007
(Dagbladet.no): De fleste av oss har opplevd déjà vu - følelsen av å ha opplevd noe tidligere. Det fins mange spekulasjoner rundt hva som kan være årsaken - noen tror det skyldes klarsynthet, synske evner eller minner fra et tidligere liv - men nå mener en gruppe hjerneforskere å ha løst gåten, skriver Reuters. (...)
Hvordan husker vi?
Tidsskr Nor Lægeforen 2007; 127: 1483 (31.5.2007)
Mange minner er basert på hendelser som kun skjer én gang, men mange hendelser er svært like. Hva gjør hjernen for å unngå sammenblanding? (...)
Hjernens vandveje fundet
netdoktor.com 30.5.2007
Når man får et slagtilfælde eller et hårdt slag i hovedet ved ulykker, opstår der ofte en vandsamling i hjernen. Vandet presser hårdt på dele af hjernen, så risikoen for at få varige mén eller i værste fald dø af tilstanden er overhængende.
Man har hidtil ikke kunnet finde ud af, hvordan vandet flyder ind i hjernen, men nu har norske forskere i dyreforsøg kunne påvise, hvordan det fungerer. Og de mener, det vil medføre, at man kan forhindre skader.
”Man kan blokere for vandet med medicin, og vi har flere stoffer, som ser lovende ud,” siger professor Ole Petter Ottersen, Oslo Universitet. (...)
Hjernen tilhører alle
Jon Henrik Laake
Tidsskr Nor Lægeforen 2007; 127: 1401 (15.5.2007)
Et godt selvbilde er fint å ha, men et realistisk selvbilde er heller ikke å forakte. Det er det grunn til å minne om når norske nevrologer nå hevder at «hjernen tilhører nevrologene» (1). Dette kunne vært omformulert som et morsomt ordspill, men fremstår istedenfor som tåpelig for alle oss ikke-nevrologer som har omsorg for pasienters hjerner i vårt daglige virke. (...)
Study Probes Parkinson Drugs' Effect on Motivation
healthfinder.gov 26.4.2007
Agents that act on dopamine may trigger compulsion, apathy (...)
THURSDAY, April 26 (HealthDay News) -- Drugs that modify levels of a key brain chemical, called dopamine, also influence how people react to success and failure, British scientists say.
They measured the effects of these drugs -- often used to fight Parkinson's disease -- on the striatum, the part of the brain that's stimulated by rewards.
Dopamine is a naturally-produced chemical that transmits signals between nerve cells. (...)
"This study may explain why dopamine depletion leads to the lack of motivation often described in people with Parkinson's disease and how dopamine replacement therapy can cause compulsive behaviors, such as overeating and gambling addictions, in the same people," Pessiglione said.
The study was expected to be presented at the American Academy of Neurology's annual meeting, in Boston, April 28 to May 5.
More information
Find out more about Parkinson's disease at the National Parkinson Foundation.
(SOURCE: American Academy of Neurology, news release, April 26, 2007) (...)
Toxic Factor Linked to ALS Neuron Death
medpagetoday.com 25.4.2007
NEW YORK, April 25 -- Glial cells -- long thought to be passive onlookers as motor neurons die in amyotrophic lateral sclerosis -- are actually major players, according to two research groups. (...)
Point out that these studies are preliminary and more research is needed.
In companion papers published online in Nature Neuroscience, scientists at Columbia here and at Harvard reported that in ALS glial cells can secrete a toxic factor that selectively kills motor neurons. (...)
Smerter svekker hukommelsen
vg.no 25.4.2007
Har du vondt i ryggen? Det kan være årsaken til at du ikke husker å ringe legen eller kjøpe brød. (...)
Han forklarer at smerten trenger seg på og konstant forstyrrer oss når vi skal prøve å konsentrere oss om noe. Den hindrer rett og slett lagring av informasjon på "harddisken". (...)
Også forskerteamet fra Keele University i England har en teori om at smerte utløser stress og at dette påvirker hukommelsen.
- En annen forklaring kan henge sammen med steroider som pasientgruppen vår kanskje har vært utsatt for, skriver forskerne i tidsskriftet Psychosomatic Medicine.
De som forbrukte moderate eller store mengder smertestillende medisiner, hadde nemlig større problemer med korttidshukommelsen enn de som gikk på lavdoser. (...)
Brain Structure Changes Before Memory Loss: Study
healthfinder.gov 20.4.2007
Scans reveal makeup altered about 4 years before diagnosis of cognitive impairment
FRIDAY, April 20 (HealthDay News) -- Brain structure changes occur years before a person shows signs of memory loss caused by Alzheimer's disease or other forms of dementia, a new U.S. study suggests.
The study, published in the April 17 issue of the journal Neurology, included 136 healthy people over the age of 65 who underwent brain scans and cognitive tests at the start of the study and were all found to be cognitively normal. They were then assessed once a year for five years.
By the end of the five years, 23 participants had developed mild cognitive impairment (MCI), and nine of those 23 people were later diagnosed with Alzheimer's disease. (...)
Tankene vandrer når hjernen hviler
Notiser
Tidsskr Nor Lægeforen 2007; 127 (19.4.2007)
Det er et velkjent fenomen at tankene har en tendens til å vandre når hjernen ikke utsettes for spesielle krav til tankevirksomhet. Det er imidlertid lite kjent hvordan den arbeider under slike forhold.
Amerikanske og skotske forskere har tatt MR-bilder av hjernen mens personer var uvirksomme, utførte velkjente handlinger eller startet opp med nye oppgaver (Science 2007; 315: 393 - 5). (...)
(Anm: Wandering Minds: The Default Network and Stimulus-Independent Thought. Science 2007; 315: 393 - 5.)
Hjernen tolker alt misbruk likt
aftenposten.no 17.4.2007
Narkomane, spilleavhengige, røykere og shoppeavhengige reagerer likt. (...)
Olika missbruk lika farligt för hjärnan
netdoktor.passagen.se 16.4.2007
Alla kända varianter av beroende skadar två viktiga funktioner i hjärnan; belöningssystemet och impulskontrollen. Det visar ny forskning. Vid vällust ökar hjärnans produktion av signalsubstansen dopamin. Dopaminet stimulerar vårt belöningssystem som styr våra mest grundläggande behov som att äta, dricka och fortplanta oss, ju mer dopamin desto större vällust. Dopamin är också med och påverkar det centrum i hjärnan som styr våra impulshandlingar. Vid den nya forskningen har man sett att vid olika sorters missbruk ökas halten dopamin och ger en upplevelse av vällust. Vid upprepad tillförsel av ökat dopamin minskar kroppens egen förmåga att öka dopaminet och på så sätt blir vissa viktiga funktioner i hjärnan kidnappat av missbruket. (...)
Blakke hjerner tenner på småpenger
forskning.no 11.4.2007
Hvis du har dårlig råd, så er hjernen din giret på småpenger. Rikfolk derimot lar vekslepengene seile sin egen sjø og tenker på andre ting, har britiske psykologer funnet ut.
Ved å scanne hjernen til forsøkspersoner med forskjellige inntekter fant forskerne ut at hjernene til de fattigste lyste opp på magnetresonans-scanneren (MRI) ved utsikten til en mynt. De var også mer motiverte til å løse oppgaver hvis de fikk en liten pengebelønning. (...)
Abstract i tidsskriftet Neuron (...)
Tren hjernen - bli 20 år yngre
dn.no 16.3.2007
Ved å trene hjernen systematisk kan du holde tritt med dine yngre kolleger på jobben. (...)
Sleeping Pill Wakes Woman After 2 Years in Coma
healthfinder.gov 13.3.2007
Ambien 'mini-miracle' may give more insight into how the brain works, experts say.
TUESDAY, March 13 (HealthDay News) -- A dose of the prescription sleep aid Ambien had the opposite effect on one French woman, awakening her from a two-year coma.
The 48-year-old woman suffered from akinetic mutism -- a sort of persistent coma in which the patient is alert but can neither speak nor move. She had lain in this state after sustaining damage to the frontal lobe of her brain due to a lack of oxygen caused by an attempted suicide by hanging.
But one day she was given zolpidem (Ambien) to treat ongoing insomnia. (...)
The results are published in the March issue of Annals of Neurology. (...)
"I'm sure that anyone that has a relative who is in a long-term coma is going to be interested in having the doctor try Ambien and see if it makes a difference. So we may get more case reports very quickly," he said. (...)
Brief Awakening From a Coma
nytimes.com 8.3.2007
DENVER, March 8 — A woman who has been in a coma-like state for more than six years awoke for three days this week to talk with family members and eat her favorite foods before relapsing. (...)
“We may have to rethink these people that have been called vegetative in nursing homes who may have some awareness of their horrible circumstances,” said Dr. Bjork. “It goes against the grain of what we thought.” (...)
Traumer kan skade barnehjernen
mozon.no 9.3.2007
Traumatisk stress etter sterke hendelser kan skade barns hjerner, viser en ny studie. (...)
Studien, som har stått på trykk i tidsskriftet Pediatrics, viste også at barna hadde høyere nivåer av stresshormonet kortisol, som har vist seg å drepe hippocampus-celler i dyr. En mindre hippocampus kan igjen føre til at barnet får mer angst og at evnen til å takle stress blir dårligere.
Dette kan gi en ond sirkel: Mye kortisol skader hippocampus, noe som igjen øker angstfølelsen, skriver BBC på nett. (...)
Genes may be to blame for infidelity
bbc.co.uk 7.6.2004
Some people may be genetically programmed to be unfaithful to their partner, a scientist has claimed.
Professor Tim Spector, of the Twin Research Unit at St Thomas' Hospital, London, says he has evidence of a genetic component to infidelity.
Focusing on women, he found that if one of a pair of twins had a history of infidelity, the chances her sister would also stray were about 55%.
In general it is estimated that just 23% of women are not faithful. (...)
Websidene er designet og tilrettelagt av Hein Tore Tønnesen © 2009