By PATRICIA COHEN Grab a timer and set it for one minute. Now list as many creative uses for a brick as you can imagine. Go. Images from brain research conducted by the Mind Research Network. While intelligence and skill are associated with the fast and efficient firing of neurons in the brain, subjects who tested high in creativity had thinner white matter and connecting axons that slow nerve traffic. In these images, the green tracks show the white matter being analyzed. The yellow and red spots show where creativity corresponds with slower nerve traffic. The blue areas show where “openness to experience,” associated with creativity, corresponds with slower nerve traffic. The question is part of a classic test for creativity, a quality that scientists are trying for the first time to track in the brain. They hope to figure out precisely which biochemicals, electrical impulses and regions were used when, say, Picasso painted “Guernica,” or Louise Nevelson assembled her wooden sculptures. Using M.R.I. technology, researchers are monitoring what goes on inside a person’s brain while he or she engages in a creative task. Yet the images of signals flashing across frontal lobes have pushed scientists to re-examine the very way creativity is measured in a laboratory. “Creativity is kind of like pornography — you know it when you see it,” said Rex Jung, a research scientist at the Mind Research Network in Albuquerque. Dr. Jung, an assistant research professor in the department of neurosurgery at the University of New Mexico, said his team was doing the first systematic research on the neurology of the creative process, including its relationship to personality and intelligence. Copyright 2010 The New York Times Company

Keyword: Attention
Link ID: 14056 - Posted: 06.24.2010

by Greg Miller Where did I leave my car keys? Did I come into this room to get something? And what was that person's name again? Getting old often means getting a little forgetful. Now researchers working with mice think they have found a new reason why. They've identified molecular changes in the brains of aging mice that prevent learning and memory genes from being switched on as they are in younger animals. If the findings translate to humans, they may one day lead to drugs that stave off dementia or even the normal cognitive declines of old age. Indeed, a certain class of drugs already in development for treating cancer might fit the bill. Previous studies had found age-related changes in gene expression in the hippocampus, a crucial memory center in the brain. Other work implicated histones—tiny protein spools that control gene expression by winding or unwinding DNA—in learning and memory. Neuroscientist André Fischer of the European Neuroscience Institute in Göttingen, Germany, and colleagues wanted to probe the histone connection further. They hypothesized that aging might change how histones function, causing alterations in gene expression that contribute to memory problems. To test the idea, Fischer and colleagues compared old and young mice. Old mice don't have car keys to lose track of, but they do struggle to remember a place where they once received a nasty shock or a hidden platform in a pool of murky water. The team found staggering differences in gene expression between juvenile 3-month-old mice and 16-month-old mice (equivalent to late middle age in humans). An hour after being trained to associate a particular chamber with an impending shock to the foot, nearly 2000 genes in the hippocampus became more active in the younger mice compared with just six genes in the older mice. © 2010 American Association for the Advancement of Science.

Keyword: Learning & Memory; Alzheimers
Link ID: 14055 - Posted: 06.24.2010

By Katherine Harmon Shakespeare's Lady Macbeth could never wash away the guilt of murder from her hands, but research has shown that the simple act of hand washing—or even using a wipe—can in fact help people clean their conscience of dirty deeds. A new study, published online May 6 in Science, reveals the power of hand washing to ease people's minds about even mundane decisions. Often, when people make decisions—no matter how big or small—they tend to justify them, rationalizing often beyond reason that their choice was by far the best. Resolving the sense of cognitive dissonance vastly decreased in subjects who washed their hands after having to make a simple choice. In an experiment, 40 subjects had to pick and rank 10 of 30 CDs that they would like to own as if they were completing a consumer survey. They were then given the choice of the fifth- and sixth-ranked CDs. Afterward, as part of an unrelated task, subjects took a survey about liquid soap. Half of the participants were given a soap bottle to assess, and the other half were instructed to try the soap out by washing their hands. Last, the participants were asked to rerank the 10 CDs. "People who merely examined the soap bottle dealt with their doubts about their decision by changing how they saw their CDs," Norbert Schwarz, of the Department of Psychology at the University of Michigan in Ann Arbor and a co-author on the study, said in a prepared statement. "They saw the chosen CD as much more attractive than before and the rejected CD as much less attractive." Those who had washed their hands, however, appeared to have reduced cognitive dissonance and rated their chosen and rejected CDs about as they had before having to choose between them. © 2010 Scientific American,

Keyword: Emotions
Link ID: 14054 - Posted: 06.24.2010

David Perlman, Chronicle Science Editor Only 10 years after scientists triumphantly decoded the human genome, an international research team has mapped the genes of the long-extinct Neanderthal people and report there's a little bit of Neanderthal in all of us. The remarkable finding could answer a question that has been hotly debated among anthropologists for decades: whether our human ancestors and the Neanderthals interbred some time after both species left Africa many thousands of years ago. The report, published today in the journal Science, capped more than five years of intensive work by a group of 56 international scientists led by German paleogeneticist Svante Pääbo and Richard E. Green of UC Santa Cruz. Edward M. "Eddy" Rubin, director of the Department of Energy's Joint Genome Institute in Walnut Creek, called the major project "a terrific piece of work and a monumental endeavor," The project's scientists used tiny specks of powdered bone retrieved from three Neanderthal females who died in a Croatian cave more than 40,000 years ago to complete the draft of the Neanderthal genome. They then compared the genes to those of modern humans living today in five different regions of the world: France, Papua New Guinea, China, and southern and northern Africa. The scientists analyzed 4 billion units of Neanderthal DNA, called nucleotides - at least 60 percent of the Neanderthal's entire genome. While incomplete, Pääbo told reporters during a teleconference this week that 60 percent "is a very good statistical sample of the entire genome." © 2010 Hearst Communications Inc.

Keyword: Evolution
Link ID: 14053 - Posted: 06.24.2010

by Bob Holmes PEOPLE are extraordinarily skilled at spotting cheats - much better than they are at detecting rule-breaking that does not involve cheating. A study showing just how good we are at this adds weight to the theory that our exceptional brainpower arose through evolutionary pressures to acquire specific cognitive skills. The still-controversial idea that humans have specialised decision-making systems in addition to generalised reasoning ability has been around for decades. Its advocates point out that the ability to identify untrustworthy people should be favoured evolutionarily, since cheats risk undermining the social interactions in which people trade goods or services for mutual benefit. To test whether we have a special ability to reason about cheating, Leda Cosmides, an evolutionary psychologist at the University of California, Santa Barbara, and her colleagues used a standard psychological test called the Wason selection task, which tests volunteers' ability to reason about "if/then" statements. The researchers set up scenarios in which they asked undergraduate volunteers to imagine they were supervising workers sorting applications for admission to two schools: a good one in a district where school taxes are high, and a poor one in an equally wealthy, but lightly taxed district. The hypothetical workers were supposed to follow a rule that specified "if a student is admitted to the good school, they must live in the highly taxed district". © Copyright Reed Business Information Ltd

Keyword: Emotions; Evolution
Link ID: 14052 - Posted: 06.24.2010

By Katie Moisse Oh, so close. Just one more try. It's hard to understand what keeps problem gamblers betting after a long losing streak. But a new study published May 5 in The Journal of Neuroscience suggests their brains' reward centers, part of the dopamine system (so-called because the neurons release the neurotransmitter dopamine), react the same way to a "near miss" as they would to a win. Researchers from the University of Cambridge, U.K., used functional magnetic resonance imaging (fMRI) to scan the brains of 20 gamblers with varying degrees of gambling intensities while they played a computerized slot machine. The brain reward centers were active in problem gamblers even when the slot machine icons almost lined up but didn't. So the near miss delivered the dopamine, if not the dollars. "These findings are exciting because they suggest that near-misses may elicit a dopamine response in the more severe gamblers, despite the fact that no actual reward is delivered," said study co-author Luke Clark in a prepared statement. "If these bursts of dopamine are driving addictive behavior, this may help to explain why problem gamblers find it so difficult to quit." © 2010 Scientific American

Keyword: Drug Abuse
Link ID: 14051 - Posted: 06.24.2010

A handful of Canadians with multiple sclerosis have had an experimental surgical procedure under the radar in this country, despite lack of proof of its safety or effectiveness. The surgery is based on the theory that blocked veins in the neck and chest contribute in some way to symptoms of MS. It's thought that opening up the veins using balloon angioplasty improves the condition. The procedure is officially not available in Canada. But Bill Harrison said he had the surgery in Victoria just over three weeks ago, paid for by B.C.'s health plan. Harrison, who has now moved to Toronto, was about to spend to $19,000 to travel to India for the surgery when he had the procedure at Victoria General Hospital. Dr. Mark Godley of False Creek Healthcare Centre in Vancouver arranged Harrison's surgery as a routine vascular procedure to fix a circulation problem. "The treatment was performed based on the fact that there was a disorder, a vascular disorder, and there was not the label of the association with MS," Godley said. Harrison said he couldn't have waited any longer because he was days away from being bed-ridden. "I do not understand what the obstacles are," Harrison said, sitting on a park bench in Toronto. "What I hear is, 'It takes time, it has to be tested.' I've already tested it. It works. I got my life back, yes!" © CBC 2010

Keyword: Multiple Sclerosis
Link ID: 14050 - Posted: 06.24.2010

By PAUL BLOOM Not long ago, a team of researchers watched a 1-year-old boy take justice into his own hands. The boy had just seen a puppet show in which one puppet played with a ball while interacting with two other puppets. The center puppet would slide the ball to the puppet on the right, who would pass it back. And the center puppet would slide the ball to the puppet on the left . . . who would run away with it. Then the two puppets on the ends were brought down from the stage and set before the toddler. Each was placed next to a pile of treats. At this point, the toddler was asked to take a treat away from one puppet. Like most children in this situation, the boy took it from the pile of the “naughty” one. But this punishment wasn’t enough — he then leaned over and smacked the puppet in the head. This incident occurred in one of several psychology studies that I have been involved with at the Infant Cognition Center at Yale University in collaboration with my colleague (and wife), Karen Wynn, who runs the lab, and a graduate student, Kiley Hamlin, who is the lead author of the studies. We are one of a handful of research teams around the world exploring the moral life of babies. Like many scientists and humanists, I have long been fascinated by the capacities and inclinations of babies and children. The mental life of young humans not only is an interesting topic in its own right; it also raises — and can help answer — fundamental questions of philosophy and psychology, including how biological evolution and cultural experience conspire to shape human nature. In graduate school, I studied early language development and later moved on to fairly traditional topics in cognitive development, like how we come to understand the minds of other people — what they know, want and experience. Copyright 2010 The New York Times Company

Keyword: Emotions; Development of the Brain
Link ID: 14049 - Posted: 06.24.2010

Lizzie Buchen The centrifuge tube was the first that neuroscientist Philip Sabes had held in his hand for 15 years. The small, polypropylene container, no larger than a AAA battery, held a few drops of liquid at its base. It looked like water but, Sabes had been told by his collaborators, it contained a high concentration of viruses — and he had to get them into the brain of a monkey. "Honestly, I really felt like I didn't know what I was doing," says Sabes, of his work last November at the Keck Center for Integrative Neuroscience at the University of California, San Francisco (UCSF). "I basically knew nothing about molecular biology. This was way outside my area of expertise." Sabes's training was in physics, machine learning and human perception, and his lab has been working with humans and non-human primates to develop models of how the brain turns perceptions into actions; for example, seeing a fly and swatting it away. He's not alone in his molecular-biology naivety at the Keck Center — there is no cell-culture facility, no PCR machine and no bench-top centrifuge. The centre's one ice machine spits out large cubes instead of the crushed ice routinely used for chilling reagents — it was ordered by mistake, and no one has cared enough to fix the situation. Sabes and his colleagues have had no need for such apparatus. Researchers in their field of 'systems neuroscience' try to understand how networks of neurons process sensations and control behaviours such as learning and decision-making. And up to this point, much of their progress has been made using electrophysiology, stimulating and recording from the brains of animals as they perform a task or develop a new skill. © 2010 Nature Publishing Group,

Keyword: Miscellaneous
Link ID: 14048 - Posted: 06.24.2010

by David Wolman MICHELLE Dawson can't handle crowded bus journeys, and she struggles to order a cup of coffee in a restaurant because contact with strangers makes her feel panicky. Yet over the past few years, Dawson has been making a name for herself as a researcher at the Rivière-des-Prairies hospital, part of the University of Montreal in Canada. Dawson's field of research is the cognitive abilities of people with autism - people such as herself. She is one of a cadre of scientists who say that current definitions of this condition rely on findings that are outdated, if not downright misleading, and that the nature of autism has been fundamentally misunderstood for the past 70 years. Medical textbooks tell us that autism is a developmental disability diagnosed by a classic "triad of impairments": in communication, imagination and social interaction. While the condition varies in severity, about three-quarters of people with autism are classed, in the official language of psychiatrists, as mentally retarded. Over the past decade or so, a growing autistic pride movement has been pushing the idea that people with autism aren't disabled, they just think differently to "neurotypicals". Now, research by Dawson and others has carried this concept a step further. They say that auties, as some people with autism call themselves, don't merely think differently: in certain ways they think better. Call it the autie advantage. © Copyright Reed Business Information Ltd.

Keyword: Autism
Link ID: 14047 - Posted: 06.24.2010

People who get less than six hours sleep per night have an increased risk of dying prematurely, researchers said on Wednesday. Those who slumbered for less than that amount of time were 12 percent more likely to die early, though researchers also found a link between sleeping more than nine hours and premature death. "If you sleep little, you can develop diabetes, obesity, hypertension and high cholesterol," Francesco Cappuccio, who led research on the subject at Britain's University of Warwick, told AFP. The study, conducted with the Federico II University in Naples, Italy, aggregated decade-long studies from around the world involving more than 1.3 million people and found "unequivocal evidence of the direct link" between lack of sleep and premature death. "We think that the relation between little sleep and illness is due to a series of hormonal and metabolical mechanisms," Cappuccio said. The findings of the study were published in the Sleep journal. Cappuccio believes the duration of sleep is a public health issue and should be considered as a behavioral risk factor by doctors. "Society pushes us to sleep less and less," Cappuccio said, adding that about 20 percent of the population in the United States and Britain sleeps less than five hours. © 2010 Discovery Communications, LLC.

Keyword: Sleep
Link ID: 14046 - Posted: 06.24.2010

by Linda Geddes GENE hunters looking for the causes of strokes and other common diseases may have been looking in the wrong place. It seems that common mutations in the DNA of mitochondria, tiny structures that form the energy powerhouses of cells, may protect people against strokes, and play a role in Parkinson's and other complex diseases. Until now mitochondrial DNA has only been associated with a few, rare disorders: catastrophic mutations can cause diseases such as MELAS, which results in muscle weakness and seizures. But recent studies have hinted that less problematic - but far more common - mitochondrial mutations might also be implicated in diseases with no obvious link to energy demand, including strokes. Mitochondrial DNA varies from person to person, but humans can generally be divided into broad "haplogroups" on the basis of the combinations of mutations they possess. Patrick Chinnery at the University of Newcastle, UK, and his colleagues assigned haplogroups to 950 people who'd had strokes, 340 people with heart disease symptoms, and 2939 healthy volunteers, all of whom live in Oxfordshire, UK. They found that among those people who'd had strokes, half as many belonged to haplogroup "K" as would be expected in the general population. The researchers conclude that K - which accounts for around 9 per cent of people of European ancestry - decreases the risk of stroke by 50 per cent compared with the other haplogroups. This makes it one of the best predictors of stroke risk identified so far - on a par with aggressively lowering blood pressure (The Lancet Neurology, DOI: 10.1016/S1474-4422(10)70083-1). © Copyright Reed Business Information Ltd.

Keyword: Stroke; Genes & Behavior
Link ID: 14045 - Posted: 06.24.2010

by Greg Miller People with Tourette syndrome are plagued by unwanted movements and verbal tics that run the gamut from extra eye blinks and grimaces to involuntary grunts or even cursing. Although the disorder tends to run in families, little is known about its genetic basis. Now researchers have found a mutated gene that appears to cause the disorder in one extremely unusual family with nine afflicted individuals. Although this mutation is not the cause of the vast majority of Tourette syndrome cases, it may push researchers to investigate a mechanism—and potential treatments—they otherwise would not have considered. Since the French neurologist Georges Gilles de la Tourette first described his namesake condition 125 years ago, scientists have puzzled over the cause. Much recent attention has focused on a brain region called the basal ganglia that is involved in repetitive behaviors and on the neurotransmitter dopamine. In 2005, a team led by child psychiatrist and geneticist Matthew State of Yale University School of Medicine, reported one of the first genetic clues to the disorder, a mutation in a gene called SLITRK1 that seems to be responsible for a rare handful of cases. But the function of SLITRK1 and its contribution to Tourette syndrome are still largely a mystery. In the new study, State and colleagues examined a family in which the father and all eight offspring (six sons and two daughters) have the syndrome. Extensive genetic detective work led them to a mutation in a gene called HDC, which encodes L-histidine decarboxylase, an enzyme involved in the production of histamine, a signaling molecule with a wide variety of roles throughout the body. The same mutation was present in all members of the family who had Tourette but was absent in thousands of DNA samples from control subjects, who included unrelated people with similar ethnic backgrounds as well as a group of 720 Tourette patients, the researchers report today in The New England Journal of Medicine. The mutated version of the HDC gene likely results in a truncated version of the enzyme, which would result in reduced histamine levels, State says. © 2010 American Association for the Advancement of Science

Keyword: Tourettes; Genes & Behavior
Link ID: 14044 - Posted: 06.24.2010

by Mark Buchanan FROM outside economist Ernst Fehr's office at the University of Zurich in Switzerland you would have no idea that he had been tipped to win a Nobel economics prize. For one thing, the name on the door looks as if it has been dashed off on the cheapest of departmental printers. But Fehr himself seems to fit the bill. Smiling broadly, he extends a hand, eager to talk about his experiences, whether favourable, amusing or confounding. Ironically, he says, it was one of the latter that led to his current success. In reality, it all started with failure. Twenty years ago, Fehr had a seemingly sensible idea - that a deep-seated human preference for fairness might play an important role in economics. He thought it might explain why companies - even in countries without a minimum wage - don't offer jobs paying wages far below the standard, despite research showing plenty of unemployed people would willingly take the work. It doesn't happen, he suggested, because companies know that workers hired at a lower wage feel they are being cheated, causing them to grow disgruntled and work less hard. Fehr wrote a paper on the idea that fairness matters, which was promptly rejected by every prestigious economic journal he sent it to on the grounds that people only care about how much they get for themselves, not how that compares to what others might receive. "Most economists would be deeply unhappy if paid less than what they consider to be fair, so I thought I had a convincing answer," Fehr says. "But I found out that in theoretical economics, fairness just doesn't count." © Copyright Reed Business Information Ltd.

Keyword: Emotions; Evolution
Link ID: 14043 - Posted: 06.24.2010

By STEPHANIE NANO NEW YORK - Researchers are reporting the first scientific evidence that a hormone banned in sports can boost athletic performance. The improvement from human growth hormone was modest, and only in sprinting. It didn't increase strength or fitness. Athletes likely to benefit are those in sprint events like running or swimming that require a burst of energy, and where a split second can decide the winner, the Australian researchers said. Human growth hormone, or HGH, is one of many substances banned by the Olympics and other sports even though there hasn't been any good proof that it can enhance performance. Previous studies in athletes have been small and brief. Story continues below ↓advertisement | your ad here The new research tested it in about 100 recreational athletes for two months. "This is the first demonstration that growth hormone improves performance and justifies its ban in sport," said Dr. Ken Ho, who led the study at the Garvan Institute of Medical Research in Sydney. Human growth hormone is made by the pituitary gland and promotes growth of bone and other tissue. A manufactured version is available, but its use is restricted to certain conditions in children and adults, including short stature, growth hormone deficiency and wasting from AIDS. Copyright 2010 The Associated Press

Keyword: Hormones & Behavior
Link ID: 14042 - Posted: 05.04.2010

The risk of suicide or suicide attempts by adults who start taking antidepressants does not seem to vary by the type of medication, a new study finds. Study author Dr. Sebastian Schneeweiss of Brigham and Women's Hospital and Harvard Medical School and his co-authors aimed to find out whether the risk of suicide is equal across different classes of antidepressants or whether some classes offer safety advantages in adults. "There was no clinically meaningful difference in risk among individuals taking different classes of medications," the researchers concluded in the May issue of the journal Archives of General Psychiatry. The researchers analyzed pharmacy and hospital records of 87,543 adults in British Columbia who started taking antidepressants between 1997 and 2005. During the first year of antidepressant use, 751 people attempted suicide and 104 committed suicide, according to a review of hospital records and death certificates. Most of the suicides and suicide attempts occurred in the first six months after starting treatment. The researchers found no clinically meaningful difference in risk among those taking different classes of antidepressants such as: © CBC 2010

Keyword: Depression
Link ID: 14041 - Posted: 06.24.2010

By JOHN TIERNEY The human ego has never been quite the same since the day in 1960 that Jane Goodall observed a chimpanzee feasting on termites near Lake Tanganyika. After carefully trimming a blade of grass, the chimpanzee poked it into a passage in the termite mound to extract his meal. No longer could humans claim to be the only tool-making species. The deflating news was summarized by Ms. Goodall’s mentor, Louis Leakey: “Now we must redefine tool, redefine Man, or accept chimpanzees as human.” So what have we actually done now that we’ve had a half-century to pout? In a 50th anniversary essay in the journal Science, the primatologist William C. McGrew begins by hailing the progression of chimpanzee studies from field notes to “theory-driven, hypothesis-testing ethnology.” He tactfully waits until the third paragraph — journalists call this “burying the lead” — to deliver the most devastating blow yet to human self-esteem. After noting that chimpanzees’ “tool kits” are now known to include 20 items, Dr. McGrew casually mentions that they’re used for “various functions in daily life, including subsistence, sociality, sex, and self-maintenance.” Sex? Chimpanzees have tools for sex? No way. If ever there was an intrinsically human behavior, it had to be the manufacture of sex toys. Considering all that evolution had done to make sex second nature, or maybe first nature, I would have expected creatures without access to the Internet to leave well enough alone. Copyright 2010 The New York Times Company

Keyword: Sexual Behavior; Evolution
Link ID: 14040 - Posted: 06.24.2010

By Sandy Fritz Old age brings with it a host of physical woes, and among the most common is hearing loss. Forty percent of Americans older than 65 suffer from hearing loss, and by 2030 some 65 million Americans will be hard of hearing. Now joint work by researchers at the universities of Wisconsin, Florida, Washington and Tokyo has uncovered the mechanism behind age-related hearing loss, and with the help of simple chemicals, they have managed to keep old mice hearing as well as young pups. The team investigated a molecular mechanism that has been implicated in many age-related maladies but had not yet been tied to hearing loss. Our bodies are constantly exposed to short-lived organic molecules known as free radicals, which harm cells in a process called oxidation. When cells are stressed by oxi­dative damage, they release a protein called Bak, which triggers a cascade of events culminating in cell suicide. To test whether this mechanism was responsible for age-related hearing loss, the researchers compared normal mice with genetically engineered mice that do not have the gene necessary to make Bak. These Bak-deficient mice failed to develop hearing problems as they aged, but the ordinary mice, subjected to the same oxidative stress, became hard of hearing. Although most cells in the body are replaced with new cells after they die, the inner ear’s sensory nerve cells and ganglion neurons do not regenerate, so hearing loss is permanent. © 2010 Scientific American

Keyword: Hearing; Apoptosis
Link ID: 14039 - Posted: 06.24.2010

By Katherine Harmon The immune system's cells work hard to fight off infections. But new research is uncovering their important role in cognition, and a study published online May 3 in The Journal of Experimental Medicine reveals how the immune system's T cells, which aren't present in the brain, can impact learning and memory. Inflammation around the brain can hamper thinking, and attacks by inflammatory immune cells have been linked to declines in cognitive ability in patients who have, for example, multiple sclerosis or dementia. "Unexpectedly, however, T cells were recently shown to support learning and memory, though the underlying mechanism was unclear," wrote the study's authors, led by Noël Derecki of the Department of Neuroscience at the University of Virginia in Charlottesville. To uncover the mechanisms at work, Dereki and colleagues set out to determine why mice deficient in T cells performed poorly in maze learning tests even though T cells themselves are not normally found in the brain and are generally involved with inflammatory responses. The answer lay in a series of interactions that involves the meninges, or the membranes that surround the central nervous system, where T cells have been shown to congregate after maze training in mice. Of particular interest to researchers were T cells that make the immune protein IL-4, a cytokine that inhibits other compounds that encourage swelling. When these T cells had been knocked out of mice, the area around the brain and central nervous system had more myeloid cells, which seem to spur inflammation and impair learning. © 2010 Scientific American

Keyword: Learning & Memory; Neuroimmunology
Link ID: 14038 - Posted: 06.24.2010

By Nathan Seppa People with post-traumatic stress disorder seem to accumulate an array of genetic changes different from those found in healthy people, researchers report online May 3 in the Proceedings of the National Academy of Sciences. The new findings, while showing differences between people with and without PTSD, don't shed light on whether these differences might play a role in PTSD, says study coauthor Sandro Galea, a physician and epidemiologist at Columbia University in New York City. Only a fraction of people who witness a traumatic event develop PTSD. In an attempt to identify what makes people who develop PTSD biologically different from those who don’t, Galea and his colleagues obtained blood samples from 100 people in the Detroit area. All had been exposed to at least one potentially traumatic event, and 23 were diagnosed with PTSD. The scientists tested 14,000 genes in these blood samples for chemical changes to DNA that can affect gene activity without altering the genetic information itself. The researchers focused on the methylation of genes, a process in which a methyl molecule is added to DNA, typically turning off a gene and inhibiting production of the protein that the gene encodes. If people with PTSD have more or less methylation in specific genes, that might somehow contribute to PTSD, Galea says. © Society for Science & the Public 2000 - 2010

Keyword: Stress; Genes & Behavior
Link ID: 14037 - Posted: 06.24.2010