By R. Douglas Fields WASHINGTON, D.C.—One of the most difficult tasks to teach Air Force pilots who guide unmanned attack drones is how to pick out targets in complex radar images. Pilot training is currently one of the biggest bottlenecks in deploying these new, deadly weapons. So Air Force researchers were delighted recently to learn that they could cut training time in half by delivering a mild electrical current (two milliamperes of direct current for 30 minutes) to pilot's brains during training sessions on video simulators. The current is delivered through EEG (electroencephalographic) electrodes placed on the scalp. Biomedical engineer Andy McKinley and colleagues at the Air Force Research Laboratory at Wright–Patterson Air Force Base, reported their finding on this so-called transcranial direct current stimulation (TDCS) here at the Society for Neuroscience annual meeting on November 13. "I don't know of anything that would be comparable," McKinley said, contrasting the cognitive boost of TDCS with, for example, caffeine or other stimulants that have been tested as enhancements to learning. TDCS not only accelerated learning, pilot accuracy was sustained in trials lasting up to 40 minutes. Typically accuracy in identifying threats declines steadily after 20 minutes. Beyond accelerating pilot training, TDCS could have many medical applications in the military and beyond by accelerating retraining and recovery after brain injury or disease. The question for the Air Force and others interested in transcranial stimulation is whether these findings will hold up over time or will land in the dustbin of pseudoscience. © 2011 Scientific American,

Keyword: Learning & Memory
Link ID: 16076 - Posted: 11.26.2011

by Chelsea Whyte Name an animal that is most active during the full moon, and even those of us untouched by the charms of the Twilight movies might think werewolf. Our subject today is no mythical beast, however. The Barau's petrel is one of a handful of tropical birds that uses the moon as a kind of alarm clock. During breeding season, the bird travels to mating sites on the aptly named Reunion Island off the shore of Madagascar to meet its mate. The monogamous birds synchronise their journeys using the full moon as a kind of Bat-Signal to indicate that it's time to mate. "First arrival at the colony is crucial in the mating system of colonial animals like seabirds," writes Patrick Pinet of the University of Réunion, France. It's not uncommon for birds to take cues from the intensity of sunlight or the length of the day to determine the seasons for migration and mating. Circadian clocks are influenced by melatonin secretions, which reflect the amount and intensity of daylight. But the Barau's petrel migrates longitudinally – that is, parallel to the equator – so there isn't much difference between the hours of sunrise and sunset in winter and summer. Still, the slight changes in daylight do affect the petrels. Daily and seasonal changes in melatonin secretion indicate time of day and the time of the year for these birds. But to migrate at the right time to ensure they meet their partners, they need something that varies more reliably. © Copyright Reed Business Information Ltd.

Keyword: Biological Rhythms; Sexual Behavior
Link ID: 16075 - Posted: 11.26.2011

Chelsea Whyte, contributor A 27-year-old woman has lost her place the London 2012 Paralympic Games in what appear to be the most unusual of circumstances: Monique van der Vorst, formerly paralysed from the waist down, has regained her ability to walk. Perhaps surprisingly, though, neuroscientists say her experience is not unprecedented. van der Vorst was a handcyclist with national and international titles to her name. She has now traded her handbike for a bicycle - and has just been given one of 11 spots on the Dutch women's professional cycling team, Rabobank, according to IoL News. When she was 13, van der Vorst lost the use of her right leg after routine ankle surgery damaged her nerves. She took up handcycling, but in 2008, while she was training for the Beijing Olympics, she was hit by a car. Her spinal cord was damaged, leaving her paralysed from the waist down, yet she still entered the Olympics later that year - and won two silver medals. Last year, she was involved in another accident, this time with a cyclist. The accident left her legs tingling, and after a spell in hospital and some rehabilitation, she was able to walk again. Although van der Vorst's recovery remain unexplained, that's largely because of the speed of her recovery, according to IoL News. In fact, regaining the use of paralysed limbs is more common than we realise, according to Geoff Raisman, a neurologist at University College London. © Copyright Reed Business Information Ltd.

Keyword: Regeneration
Link ID: 16074 - Posted: 11.26.2011

By Rick Nauert PhD Senior News Editor Researchers have learned that a psychopaths brain structure is significantly different from others. University of Wisconsin-Madison researchers discovered the variance studying images of prisoners’ brains. The results could help explain the callous and impulsive anti-social behavior exhibited by some psychopaths. The study showed that psychopaths have reduced connections between the ventromedial prefrontal cortex (vmPFC), the part of the brain responsible for sentiments such as empathy and guilt, and the amygdala, which reconciles fear and anxiety. Structural changes in the brain were confirmed using two different types of brain images. Diffusion tensor images (DTI) showed reduced structural integrity in the white matter fibers connecting the two areas, while a second type of image that maps brain activity, a functional magnetic resonance image (fMRI), showed less coordinated activity between the vmPFC and the amygdala. “This is the first study to show both structural and functional differences in the brains of people diagnosed with psychopathy,” says Michael Koenigs. “Those two structures in the brain, which are believed to regulate emotion and social behavior, seem to not be communicating as they should.” © 1992-2011 Psych Central

Keyword: Aggression; Brain imaging
Link ID: 16073 - Posted: 11.26.2011

By Katherine Harmon Weakening eyesight can be sharpened with lenses, and impaired hearing can be improved with aids. What about a failing sense of smell? Detecting and distinguishing the floral bouquet of fresh honey or the miasma of bad lunchmeat might not seem quite as critical for day-to-day existence as sight or hearing. But what the nose knows is clearly important for quality of life. Research has linked this diminution, which is common in people over the age of 60 and can be exacerbated by smoking and some diseases, to loss of appetite and even to depression. Now sufferers might not have to give in to an odorless future, according to a new study, published online Sunday in Nature Neuroscience. Researchers at the New York University Langone Medical Center have found that, with some simple training, over time lab rats could actually improve their brain’s ability to distinguish smells. Without any practice rats could tell when one scent—in a mélange of 10—had been switched for another. (Researchers figured this out by waiting until the rodents were thirsty, then training them to look for water in one of a selection of holes based on what odor combination they had detected.) But their powers of discrimination were not perfect. If a scent was missing from the mix, the rats did not seem to be able to discern it from a full 10-scent combination. Other rats, however, were trained to become extra-familiar with the different combinations through repeated exposures and rewards. “We made them connoisseurs,” co-author Donald Wilson, a professor of psychiatry at NYU Langone, said in a prepared statement. © 2011 Scientific American,

Keyword: Chemical Senses (Smell & Taste)
Link ID: 16072 - Posted: 11.22.2011

By Eric Niiler Pepper spray, also known as oleoresin capsicum or OC, is made from the same naturally-occurring chemical that makes chili peppers hot, but at concentrations much higher. Its effects include temporary blindness, coughing and skin irritation. To make the spray used by law enforcement officers and police to control crowds, manufacturers take a concentrated oil made from chili peppers and combine it with water, glycol (a chemical used in shaving creams and liquid soaps) and a propellent such as nitrogen, according to Bob Nance, vice president of operations at Security Equipment Corp.,which makes pepper spray and other irritants at its Fenton, Mo., headquarters under the Sabre brand name. "We get it in a red, oily viscous syrup,” Nance said. “It’s the same thing you will find in hot sauce, but in higher concentrations." Interest in pepper spray was piqued after a video of campus police spraying peaceful protesters at the University of California, Davis, made the rounds on the internet this weekend, the university suspended its police chief and two officers. The video shows an officer spraying protesters in the face as they are sitting on the ground. "It causes your eyes to shut and makes breathing difficult," Nance said. "It can cause coughing and choking, and a severe burning sensation on your face. But it’s temporary, usually it lasts from 30 to 45 minutes." © 2011 Discovery Communications, LLC.

Keyword: Pain & Touch
Link ID: 16071 - Posted: 11.22.2011

By Laura Sanders Most caffeine addicts would tell you that coffee sharpens the mind. It turns out that in rodents, a single dose of caffeine does indeed strengthen brain cell connections in an underappreciated part of the brain, scientists report online November 20 in Nature Neuroscience. A clearer idea of caffeine’s effect on the brain could allow scientists to take advantage of its stimulating effects and perhaps even alleviate some symptoms of brain disorders. “Caffeine is something people are very interested in,” says neuroscientist Susan Masino of Trinity College in Hartford, Conn., who was not involved in the study. So far, most of caffeine’s effects have been illuminated by studies using doses much higher than an average person’s morning cup of joe, says study coauthor Serena Dudek of the National Institute of Environmental Health Sciences in Research Triangle Park, N.C. Dudek and her team looked at the effects of smaller hits of caffeine on a small part of the hippocampus. In humans, this seahorse-shaped structure is buried deep in the brain behind the ears. After feeding rats the equivalent of two human cups of coffee (two milligrams of caffeine per kilogram of body weight), the team measured the strength of nerve cells’ electrical messages in slices of brain tissue. Nerve cells in this particular nook — a brain region called CA2 — got a major jolt from caffeine, showing a bigger burst of electrical activity when researchers stimulated the cells. Nerve cells in a neighboring part of the hippocampus didn’t show this sensitivity. © Society for Science & the Public 2000 - 2011

Keyword: Drug Abuse; Sleep
Link ID: 16070 - Posted: 11.22.2011

By SINDYA N. BHANOO Grapheme-color synesthesia is a peculiar neurological condition in which people involuntarily experience colors when thinking about letters, numbers or words. They might, for instance, always see the color green along with the number four, or blue with the letter A. Neuroscientists from the University of Oxford in England are trying to determine what exactly is different about the brains of those with this type of synesthesia. In a new study, they report that people with the condition experience heightened activity in the brain region associated with vision. The study appears in the journal Current Biology. The researchers stimulated their subjects’ visual cortex using a method called transcranial magnetic stimulation. Compared with normal subjects, people with the synesthesia required only one-third the stimulation to experience phosphenes, or transient flashes of light. “We all have different thresholds in the brain, and synesthetes have a lower threshold,” said the study’s lead author, Devin Blair Terhune, a neuroscientist at Oxford. © 2011 The New York Times Company

Keyword: Vision
Link ID: 16069 - Posted: 11.22.2011

By HARRIET BROWN In patients with depression, anxiety and other psychiatric problems, doctors often find abnormal blood levels of thyroid hormone. Treating the problem, they have found, can lead to improvements in mood, memory and cognition. Now researchers are exploring a somewhat controversial link between minor, or subclinical, thyroid problems and some patients’ psychiatric difficulties. After reviewing the literature on subclinical hypothyroidism and mood, Dr. Russell Joffe, a psychiatrist at the North Shore-Long Island Jewish Health System, and colleagues recently concluded that treating the condition, which affects about 2 percent of Americans, could alleviate some patients’ psychiatric symptoms and might even prevent future cognitive decline. Patients with psychiatric symptoms, Dr. Joffe said, “tell us that given thyroid hormones, they get better.” The thyroid, a bow-tie-shaped gland that wraps around the trachea, produces two hormones: thyroxine, or T4, and triiodothyronine, known as T3. These hormones play a role in a surprising range of physical processes, from regulation of body temperature and heartbeat to cognitive functioning. Any number of things can cause the thyroid to malfunction, including exposure to radiation, too much or too little iodine in the diet, medications like lithium, and autoimmune disease. And the incidence of thyroid disease rises with age. Too much thyroid hormone (hyperthyroidism) speeds the metabolism, causing symptoms like sweating, palpitations, weight loss and anxiety. Too little (hypothyroidism) can cause physical fatigue, weight gain and sluggishness, as well as depression, inability to concentrate and memory problems. © 2011 The New York Times Company

Keyword: Hormones & Behavior; Depression
Link ID: 16068 - Posted: 11.22.2011

By NICHOLAS BAKALAR The risk factors that predict stroke also predict mental impairment, a new study has found, even in people who have never had a stroke. Researchers studied a nationally representative sample of 23,752 mentally normal, stroke-free men and women whose average age was 64, using health questionnaires and an in-home physical and mental examination. They recorded seven risk factors for stroke: three types of heart abnormality, high blood pressure, the use of blood pressure medication, diabetes and smoking. Several of the authors have received payments from pharmaceutical companies. The report appears in Neurology. The volunteers were followed for an average of more than four years. After eliminating from consideration any who had had a stroke, the researchers found 1,907 who were cognitively impaired. After controlling for age, sex, race and education, researchers found that high blood pressure and left ventricular hypertrophy independently predicted cognitive impairment, and the more risk factors a person had, the greater the risk for mental problems. The lead author, Frederick W. Unverzagt, a professor of clinical psychology at the Indiana University School of Medicine, had this advice: “The early detection and treatment of high blood pressure is what we’re advocating for folks to preserve their cognitive health.” © 2011 The New York Times Company

Keyword: Stroke; Alzheimers
Link ID: 16067 - Posted: 11.22.2011

By NICHOLAS BAKALAR Older people who go to an emergency room in pain are less likely to get medication for it than younger people with similar levels of distress, a new analysis has found. A seven-year nationwide study of emergency room patient data has found that 49 percent of patients over age 75 were given pain medication, compared with slightly more than 65 percent of those under age 75. The study, which included data on more than 88,000 emergency room visits, appeared online last month in Annals of Emergency Medicine. Elderly people who were cognitively impaired or otherwise unable to report pain were not included in the analysis, so that does not explain the finding. Although the reasons for the difference are unclear, the authors suggest that emergency room personnel may be concerned about adverse effects of pain medications on the elderly, or they may pay more attention to diagnosis in older patients and less to pain relief. “There are side effects of pain medications,” said Dr. Timothy Platts-Mills, the lead author of the study and an assistant professor of medicine at the University of North Carolina, Chapel Hill. “But in almost all cases, you can provide some pain relief for older adults by selecting appropriate medications or reducing doses.” © 2011 The New York Times Company

Keyword: Pain & Touch
Link ID: 16066 - Posted: 11.22.2011

Clive Gamble Wondering what went on in the heads of Neanderthals has rarely produced positive thoughts. H. G. Wells set the bar low in his short story The Grisly Folk in 1921, writing: “We cannot conceive in our different minds the strange ideas that chased one another through those queerly shaped brains.” Wells's hatchet job was effective. Other authors have offered sympathetic alternatives, such as Isaac Asimov's 1958 short story The Ugly Little Boy. But the idea of a 'thinking Neanderthal' has become an evolutionary oxymoron on a par with 'military intelligence' and 'airline food'. Yet cognition certainly took place in the Neanderthal brain — the largest in human evolution, housed in a long, distinctively shaped skull. In How to Think Like a Neandertal, archaeologist Thomas Wynn and psychologist Frederick Coolidge provide one of the most rounded portraits yet of a fossil human. The book covers familiar areas — diet, symbolism and language — but also includes innovative assessments of Neanderthals' capacity to tell jokes, and even speculations on what they might have dreamed about. The authors use the Neanderthals as a means of discussing the evolutionary reasons for such cognitive abilities as humour and deception. We have learned much about Neanderthals in the past 150 years. They were powerfully built and top carnivores. Their stone tools are found across Eurasia. We know from their genome sequence that the last common ancestor of Neanderthals and ourselves lived some half a million years ago. They became extinct in southern Spain as recently as 30,000 years ago. © 2011 Nature Publishing Group,

Keyword: Evolution
Link ID: 16065 - Posted: 11.22.2011

Charlotte Schubert Human neurons, derived from embryonic stem cells, can modulate the behavior of a network of host neurons, according to a study examining the cells in culture and transplanting them into a mouse brain. The findings, published today in the Proceedings of the National Academy of Sciences, lay the foundations for potential future treatments of Parkinson's disease, stroke and other conditions. Previous studies have shown that transplanted human neurons derived from stem cells look and act like functional nerve cells. For instance, such cells form connections with host neurons in the mouse brain, and receive signals from them. But it has been a challenge to show that the transplanted cells can successfully signal to and regulate the behaviour of host neurons. To address this question, Jason Weick and his colleagues at the University of Wisconsin in Madison harnessed a technique known as optogenetic targeting. This involves genetically engineering neurons to produce an ion channel (a protein-lined pore that spans the cell membrane) that opens in response to light, allowing positive ions such as sodium and calcium to flow through it and activate the neuron. In this way the researchers can selectively activate human neurons in a mixture of human and mouse cells. © 2011 Nature Publishing Group,

Keyword: Stem Cells; Neurogenesis
Link ID: 16064 - Posted: 11.22.2011

By Katherine Lymn As head of Experimental Surgical Services at the University of Minnesota, he’s been the focus of animal rights activists’ rage. Bianco estimated that up to 300 sheep are “sacrificed” each year as part of his experiments in heart valve research. Pathology staff members kill the sheep with an overdose injection of a drug similar to what a veterinarian would use to euthanize a pet. Bianco speaks out in support of animal experimentation and accepts his status as a public figure of the biomedical research industry. But he sees it differently when animal rights groups try to influence students. “My solution is to bring the students to us,” he said. He invites high school students to his lab for field trips to “counteract” PETA’s message that using animals for research is wrong. Bianco tests heart valves in animals before the valves go on to human trials. He proactively promotes research like this, which has drawn threats in the past. Activist Camille Marino, out of Florida, posted a threat against Bianco on her website negotioationisover.net in 2009. “We should not be surprised when the unconscionable violence inflicted upon animals is justifiably visited upon their tormentors,” she wrote. Animal rights organizations have demonstrated at the University in the past. In 1999, the Animal Liberation Front claimed responsibility for vandalizing research facilities and stealing more than 100 animals. © 1900 - 2011 The Minnesota Daily

Keyword: Animal Rights
Link ID: 16063 - Posted: 11.22.2011

By TARA PARKER-POPE Like most creatures on earth, humans come equipped with a circadian clock, a roughly 24-hour internal timer that keeps our sleep patterns in sync with our planet. At least until genetics, age and our personal habits get in the way. Even though the average adult needs eight hours of sleep per night, there are “shortsleepers,” who need far less, and morning people, who, research shows, often come from families of other morning people. Then there’s the rest of us, who rely on alarm clocks. For those who fantasize about greeting the dawn, there is hope. Sleep experts say that with a little discipline (well, actually, a lot of discipline), most people can reset their circadian clocks. But it’s not as simple as forcing yourself to go to bed earlier (you can’t make a wide-awake brain sleep). It requires inducing a sort of jet lag without leaving your time zone. And sticking it out until your body clock resets itself. And then not resetting it again. To start, move up your wake-up time by 20 minutes a day. If you regularly rise at 8 a.m., but really want to get moving at 6 a.m., set the alarm for 7:40 on Monday. The next day, set it for 7:20 and so on. Then, after you wake up, don’t linger in bed. Hit yourself with light. In theory, you’ll gradually get sleepy about 20 minutes earlier each night, and you can facilitate the transition by avoiding extra light exposure from computers or televisions as you near bedtime. (The light from a computer screen or an iPad has roughly the same effect as the sun.) “Light has a very privileged relationship with our brain,” says Dr. Jeffrey M. Ellenbogen, chief of sleep medicine at Massachusetts General Hospital and assistant professor of neurology at Harvard Medical School. While most sensory information is “processed” by the thalamus before being sent on its way, Ellenbogen says, light goes directly to the circadian system. © 2011 The New York Times Company

Keyword: Biological Rhythms
Link ID: 16062 - Posted: 11.21.2011

By BENEDICT CAREY Foster children are being prescribed cocktails of powerful antipsychosis drugs just as frequently as some of the most mentally disabled youngsters on Medicaid, a new study suggests. The report, published Monday in the journal Pediatrics, is the first to investigate how often youngsters in foster care are given two antipsychotic drugs at once, the authors said. The drugs include Risperdal, Seroquel and Zyprexa — among other so-called major tranquilizers — which were developed for schizophrenia but are now used as all-purpose drugs for almost any psychiatric symptoms. “The kids in foster care may come from bad homes, but they do not have the sort of complex medical issues that those in the disabled population do,” said Susan dosReis, an associate professor in the University of Maryland School of Pharmacy and the lead author. The implication, Dr. dosReis and other experts said: Doctors are treating foster children’s behavioral problems with the same powerful drugs given to people with schizophrenia and severe bipolar disorder. “We simply don’t have evidence to support this kind of use, especially in young children,” Dr. dosReis said. In recent years, doctors and policy makers have grown concerned about high rates of overall psychiatric drug use in the foster care system, the government-financed program that provides temporary living arrangements for 400,000 to 500,000 children and adolescents. Previous studies have found that children in foster care receive psychiatric medications at about twice the rate among children outside the system. © 2011 The New York Times Company

Keyword: Schizophrenia; Development of the Brain
Link ID: 16061 - Posted: 11.21.2011

By ANDREW POLLACK It has three Nobel Prize winners on its board. Its chairman, P. Roy Vagelos, is a pharmaceutical industry star who ran Merck during its heyday. Its chief scientist has written frequently cited biomedical papers. Yet for all that, Regeneron Pharmaceuticals has known mostly failure in nearly 24 years of existence, piling up cumulative losses of $1.2 billion. But that is now changing. Late Friday, the company won approval from the Food and Drug Administration for what is expected to be its first big drug — to treat the wet form of age-related macular degeneration, a leading cause of severe vision loss in the elderly. The drug, called Eylea, can be injected into the eye less frequently than the current standard, Genentech’s Lucentis, according to the labels of the two drugs. Eylea is also slightly less expensive, at $1,850 an injection versus $1,950 for Lucentis. Regeneron argues that Eylea would save the health care system thousands of dollars a year per patient, factoring in the fewer injections and also fewer doctor visits and examinations. Eylea, however, is still more expensive that Avastin, a Genentech cancer drug that costs only $50 a dose when used off-label to treat macular degeneration. Avastin accounts for more than half the macular degeneration market, despite some recent contamination incidents that have raised safety concerns. The approval is a vindication for Dr. Leonard S. Schleifer, 59, who has been chief executive since founding Regeneron in early 1988, making him almost certainly the longest-reigning chief executive in the biotechnology industry. © 2011 The New York Times Company

Keyword: Vision
Link ID: 16060 - Posted: 11.21.2011

By Alan Boyle Slides containing thin slices of Albert Einstein's brain will go on display at Philadelphia's Mutter Museum, thanks to a donation from a neuropathologist who has been holding onto the samples for decades. Lucy Rorke-Adams of the Children's Hospital of Philadelphia received the box of 46 slides in the mid-1970s from the widow of a physician who helped arrange the preparation of the brain samples, the Philadelphia Inquirer reported. Thomas Stoltz Harvey, a doctor at Princeton Hospital, conducted the autopsy on the famed physicist just hours after his death in 1955. Apparently without the family's permission, Harvey preserved Einstein's brain and sectioned it into hundreds of specimens on microscope slides for study. The controversy, as well as the strange journey of Einstein's brain, are detailed in Michael Paterniti's book "Driving Mr. Albert." Harvey and other researchers found nothing unusual about the brain's size, but there was evidence that Einstein's brain contained more than the expected proportion of glial cells, which play a role in supporting connections between neurons. Rorke-Adams, whose research focuses on comparisons of brain cells at different ages, said Einstein's brain looks remarkably youthful under a microscope: "“It does not show any of the changes that we associate with age," CBS Philly quoted her as saying. © 2011 msnbc.com

Keyword: Miscellaneous
Link ID: 16059 - Posted: 11.21.2011

Ewen Callaway A mutation that appeared more than half a million years ago may have helped humans learn the complex muscle movements that are critical to speech and language. The claim stems from the finding that mice genetically engineered to produce the human form of the gene, called FOXP2, learn more quickly than their normal counterparts. The work was presented by Christiane Schreiweis, a neuroscientist at the Max Planck Institute (MPI) for Evolutionary Anthropology in Leipzig, Germany, at the Society for Neuroscience meeting this week in Washington DC this week. Scientists discovered FOXP2 in the 1990s by studying a British family known as 'KE' in which three generations suffered from severe speech and language problems1. Those with language problems were found to share an inherited mutation that inactivates one copy of FOXP2. Most vertebrates have nearly identical versions of the gene, which is involved in the development of brain circuits important for the learning of movement. The human version of FOXP2, the protein encoded by the gene, differs from that of chimpanzees at two amino acids, hinting that changes to the human form may have had a hand in the evolution of language2. A team led by Schreiweis’ colleague Svante Pääbo discovered that the gene is identical in modern humans (Homo sapiens) and Neanderthals (Homo neanderthalensis), suggesting that the mutation appeared before these two human lineages diverged around 500,000 years ago3. © 2011 Nature Publishing Group,

Keyword: Language; Genes & Behavior
Link ID: 16058 - Posted: 11.19.2011

By Scicurious We hear a lot about PTSD these days, and with good reason. As more people confront trauma and come away with severely debilitating disorders, it becomes that much more important to understand the mechanism, in order to find ways to treat or prevent it. And one of the ways people are seeking to understand PTSD is by trying to find genetic risk factors for the disorder, in the hope that familial traits will be able to predict who might develop PTSD and who might not, allowing for preventative treatments before exposure, and better treatments after trauma. And if you’re going to study familial components in humans, one of the best ways to do that is to study twins. For this study, the authors are looking at two different groups of twins (the study is still ongoing) recruited from the Vietnam Era Twin Registry. In the first group of twins, one twin fought in the Vietnam war and got PTSD, the other twin didn’t fight. In the second group of twins, one twin fought in Vietnam and did NOT get PTSD, and the other twin did not fight. They took these groups of twins and put them in fMRI, where they exposed them to sets of fearful or non-fearful faces. Fearful faces can provoke a response from the amygdala, an area of the brain associated with processing emotions such as fear. People with PTSD are known to have differences in amygdala responses, and this study wanted to confirm this, as well as examining their twins, to see if there was any indication in twins who had not been exposed to combat. © 2011 Scientific American,

Keyword: Stress; Genes & Behavior
Link ID: 16057 - Posted: 11.19.2011