By C. CLAIBORNE RAY Q. A family member has been unable to leave the house because of severe vertigo caused by something that sounds like cochlea hydrox. What is it and what might help? A. The disorder is called cochlear hydrops, and it also involves hearing problems. Sometimes called atypical Ménière’s disease, it is caused by abnormally high fluid pressure in the part of the inner ear called the cochlea, which is involved in both balance and hearing. Pressure surges bombard the sensitive nerve endings that normally transmit information about the body’s position to the brain. Besides causing bouts of vertigo to the point of nausea and hearing problems, cochlear hydrops leads to a sense of fullness in the ear and ringing, or tinnitus, often described as a low-pitched roar. These symptoms sometime precede full-blown vertigo. The cause is not always easy to identify, and other disorders, like thyroid problems and even inflammatory infections like syphilis, should be explored. The problem can be associated with autoimmune disorders like lupus; with hormonal surges, especially in women, who make up somewhat more than half the sufferers; and with allergic attacks. Dietary changes often help avert attacks of vertigo, especially the avoidance of foods identified as triggers and substances like caffeine. A low-salt diet and diuretics can also help control the fluid pressure. Anti-inflammatory drugs like steroids are usually helpful. Copyright 2009 The New York Times Company

Keyword: Hearing
Link ID: 13567 - Posted: 06.24.2010

By Naomi Kenner and Russell Poldrack Are you a media multitasker? We know you're reading a blog, but what else are you doing right now? Take a quick inventory: Are you also listening to music? Monitoring the progress of a sports game on TV? Emailing your co-worker? Texting your friend? On hold with tech support? If your inventory has revealed a multitasking lifestyle, you are not alone. Media multitasking is increasingly common, to the extent that some have dubbed today’s teens "Generation M." People often think of the ability to multitask as a positive attribute, to the degree that they will proudly tout their ability to multitask. Likewise it’s not uncommon to see job advertisements that place “ability to multitask” at the top of their list of required abilities. Technologies such as smartphones cater to this idea that we can (and should) maximize our efficiency by getting things done in parallel with each other. Why aren’t you paying your bills and checking traffic while you’re driving and talking on the phone with your mother? However, new research by EyalOphir, Clifford Nass, and Anthony D. Wagner at Stanford University suggests that people who multitask suffer from a problem: weaker self-control ability. The researchers asked hundreds of college students fill out a survey on their use of 12 different types of media. Students reported not only the number of hours per week that they used each type of media, but also rated how often they used each type of media simultaneously with each other type of media. The researchers created a score for each person that reflected how much their lifestyle incorporated media-multitasking. © 1996-2009 Scientific American Inc.

Keyword: Attention
Link ID: 13566 - Posted: 06.24.2010

By Olga Kuchment Imagine planning your schedule for the week and seeing the days on the calendar appear before you as a spiral staircase so real you feel like you could touch it. That's what it's like to have spatial-sequence synesthesia, a condition in which people perceive numbered sequences as visual patterns. Now researchers have shown that individuals with the condition have superior memories, recalling dates and historic events much better than can the average person. Spatial-sequence synesthesia is one of several types of synesthesia, neural conditions in which senses combine in unusual ways. Grapheme-color synesthetes, for example, associate letters and numbers with colors; the number six might always look red to them. In other types of synesthesia, the word "cat" may create the taste of tomato soup, or the sound of a flute may appear as a blue cloud. Recently, scientists have wondered if synesthesia--especially spatial-sequence synesthesia--might be linked to a superior ability to form memories. So psychologist Julia Simner of the University of Edinburgh in the United Kingdom tested for unusual mnemonic skills or other mental talents in 10 spatial-sequence synesthetes. Subjects had to quickly recall the dates of 120 public events occurring between 1950 and 2008, such as the year Nelson Mandela was freed from jail in South Africa (1990) or the year My Fair Lady won the Academy Award for best picture (1965). On average, non-synesthetic volunteers were off by about 8 years for each date, but the synesthetes were wrong by only about 4 years. They could also name almost twice as many events from specified years in their own lives than could the controls. "They have this subtle extra gift," says Simner. © 2009 American Association for the Advancement of Science.

Keyword: Learning & Memory
Link ID: 13565 - Posted: 06.24.2010

People who plan to drink at parties could designate a driver or stop drinking early enough to allow their blood-alcohol levels to go down before getting behind the wheel. Drinking a cup of coffee for every cup of spiked eggnog likely won't help you drive home more safety, a study on drunken mice suggests. "It debunks the myth that you can sober somebody up with coffee," said study author Thomas Gould, a professor of psychology at Temple University in Philadelphia. Gould and his colleagues observed mice that had been given ethanol, caffeine, a combination of the two, or neither, as the rodents learned to navigate a maze in the shape of a plus sign. In one of the arms of the maze, lights went on and sound was emitted from a speaker. Since mice don't like bright, loud areas, they normally learned to avoid that area. But animals given alcohol didn't learn to avoid the unpleasant environment and didn't remember that it was dangerous, Gould's team reported in the current issue of the journal Behavioural Neuroscience, published by the American Psychological Association. "One of my colleagues says, 'You know, if you give someone who's drunk a coffee, all you're making is a wide-awake drunk,' and this kind of supports that," Gould told CBC Radio's As It Happens. © CBC 2009

Keyword: Drug Abuse
Link ID: 13564 - Posted: 06.24.2010

By Bina Venkataraman Not all foods are created equal, whether the goal is having a healthier heart or losing weight. And the same could be true when it comes to what we eat and how depressed or happy we feel, how well we learn, and whether we suffer from mental illness. A study published last month in the Archives of Internal Medicine divided a group of 106 overweight and obese people into two groups: About half spent a year following a diet low in fat - say goodbye to steak and pastries - and high in carbohydrates (breads, pastas, beans, potatoes, and rice). The other half went for a year on a low-carb, high-fat diet - have a burger, but skip the bun. In both groups, people lost an average of 30 pounds each and generally said they felt happier two months into the diet. But after a year on the diet, the people who ate less fat and more carbs continued to report feeling happier and less depressed and anxious than they had before. The other dieters, who ate more fat and less carbohydrates, felt their moods decline from the early rise they had noted. One reason for the difference, the researchers argued, might be that eating more carbohydrates than fat and protein pumps up the production in the brain of serotonin, a chemical that has been linked with improved mood and mental health. “There’s tremendous interest in how nutrition is related to brain function,’’ said Dr. Perry Renshaw, who currently is a psychiatry professor at the University of Utah School of Medicine. Renshaw is studying whether creatine - a chemical found in fish, meat, and eggs - helps women respond more quickly to antidepressants known as SSRIs (selective serotonin reuptake inhibitors). Examples of SSRIs include Prozac and Zoloft. “It does seem there are natural products that have effects on mood.’’ © 2009 NY Times Co

Keyword: Depression; Obesity
Link ID: 13563 - Posted: 06.24.2010

By Jennifer Ouellette From the annals of "How did I miss that story?": While reading a news snippet about how scientists hope to mimic the structure of a mantis shrimp's eyes to improve on the next generation of Blu-Ray players, I stumbled on the fact that there is an X-ray space telescope under development using technology based on lobster vision. It's called the Lobster All-Sky X-Ray Monitor (LASXM), and according to Nigel Bannister of the University of Leicester, the telescope would be "ideal for use as an all-sky X-ray monitor" because of its unlimited field of view." It's not a new idea: in fact, it was first proposed in the 1970s by a scientist at the University of Arizona named Roger Angel, but it's taken 30 years for optics to advance to the point where building such a technology is even possible. What makes lobsters special? Well, they have these pea-sized compound eyes made up of long, narrow square cells that give the creature a 180-degree field of view. This allows for maximum reflectivity; each cell captures a tiny amount of light, but the light enters the eye from many different angles and only then is the light focused into a single image. Lobsters don't have great image resolution, but they don't really need it. What they do have is ultra-sensitivity to detect movement, and even the polarization of light. LASXM would mimic that structure with a new technology called microchannel plates: six nested modules -- each a bundle of 3 million parallel glass channels -- that would combine to give the instrument that same 180-degree field of view. Put it orbit around the Earth aboard a satellite or the International Space Station, such that it completes its orbit every 90 minutes, and you would quickly compile a complete x-ray picture of the sky. © 2009 Discovery Communications, LLC

Keyword: Vision; Evolution
Link ID: 13562 - Posted: 06.24.2010

By Vilayanur S. Ramachandran and Diane Rogers-Ramachandran Spanish painter El Greco often depicted elongated human figures and objects in his work. Some art historians have suggested that he might have been astigmatic—that is, his eyes’ corneas or lenses may have been more curved horizontally than vertically, causing the image on the retina at the back of the eye to be stretched vertically. But surely this idea is absurd. If it were true, then we should all be drawing the world upside down, because the retinal image is upside down! (The lens flips the incoming image, and the brain interprets the image on the retina as being right-side up.) The fallacy arises from the flawed reasoning that we literally “see” a picture on the retina, as if we were scanning it with some inner eye. No such inner eye exists. We need to think, instead, of innumerable visual mechanisms that extract information from the image in parallel and process it stage by stage, before their activity culminates in perceptual ­experience. As always, we will use some striking illusions to help illuminate the workings of the brain in this processing. Compare the two faces shown in a. If you hold the page about nine to 12 inches away, you will see that the face on the right is frowning and the one on the left has a placid expression. But if you move the figure, so that it is about six or eight feet away, the ­expressions change. The left one now smiles, and the right one looks calm. © 1996-2009 Scientific American Inc

Keyword: Vision
Link ID: 13561 - Posted: 06.24.2010

by Jessica Hamzelou Promises are made to be broken, so it can be tough to tell which ones will be kept. But new-found patterns in brain activity can reveal whether someone intends to keep their word. The finding raises the possibility of using brain scans to determine the true intentions of criminals who are up for early release on parole, according to Thomas Baumgartner of the University of Zurich in Switzerland. He and his colleagues used functional magnetic resonance imaging (fMRI) to catch promise-breakers in the act. The team set up a game of trust between an investor and a trustee. In the game, an investor is given real money, which they can choose to invest in a trustee. Giving the money to the trustee increases the amount of money fivefold, but the investor runs the risk that the trustee might not share the winnings but keep all the money for themselves. Baumgartner's team ran the game twice. The first time, investors simply had to guess whether trustees would share the winnings and then made their decision accordingly. The second, trustees could promise to share the winnings with the investor, if they wanted – although the promise was non-binding. Almost all the trustees promised to always share their winnings, thereby securing investment. While some of them remained true to their word, others consistently broke their promise, keeping the hoard for themselves. © Copyright Reed Business Information Ltd

Keyword: Emotions
Link ID: 13560 - Posted: 06.24.2010

By DUFF WILSON New federally financed drug research reveals a stark disparity: children covered by Medicaid are given powerful antipsychotic medicines at a rate four times higher than children whose parents have private insurance. And the Medicaid children are more likely to receive the drugs for less severe conditions than their middle-class counterparts, the data shows. Those findings, by a team from Rutgers and Columbia, are almost certain to add fuel to a long-running debate. Do too many children from poor families receive powerful psychiatric drugs not because they actually need them — but because it is deemed the most efficient and cost-effective way to control problems that may be handled much differently for middle-class children? The questions go beyond the psychological impact on Medicaid children, serious as that may be. Antipsychotic drugs can also have severe physical side effects, causing drastic weight gain and metabolic changes resulting in lifelong physical problems. On Tuesday, a pediatric advisory committee to the Food and Drug Administration met to discuss the health risks for all children who take antipsychotics. The panel will consider recommending new label warnings for the drugs, which are now used by an estimated 300,000 people under age 18 in this country, counting both Medicaid patients and those with private insurance. Meanwhile, a group of Medicaid medical directors from 16 states, under a project they call Too Many, Too Much, Too Young, has been experimenting with ways to reduce prescriptions of antipsychotic drugs among Medicaid children. Copyright 2009 The New York Times Company

Keyword: Schizophrenia; Development of the Brain
Link ID: 13559 - Posted: 06.24.2010

Matt Kaplan After scientists had gotten them hooked on alcohol, fruit flies—apparently desperate for a buzz—drank even repulsive concoctions and relapsed after an enforced dry spell, a new study says. Because humans and fruit flies share similar chemical pathways, the finding may shed light on the still hazy genetic roots of human alcoholism—and new ways to treat it, researchers say. Common subjects of genetic experiments—due largely to their rapid reproduction rate—fruit flies have often been used to study intoxication and alcohol tolerance in previous experiments. But the researchers behind the new study took aim at addiction, "so we could later work out the genes underlying addiction-like behaviors," said co-author Anita Devineni, a neuroscience graduate student at the University of California, San Francisco (UCSF). The team presented flies with two types of liquid food, one containing ethanol, a type of alcohol. Access was unlimited, thoough the feeders were refilled only once each day. The flies preferred the alcohol-spiked food, and the more they had it, it seems, the more they craved it—the flies' tipples grew more frequent over time. © 1996-2009 National Geographic Society.

Keyword: Drug Abuse
Link ID: 13558 - Posted: 06.24.2010

By Helen Fields It's hard out there for a sexy female fruit fly. All she wants is a nice meal and a little sperm to fertilize her eggs, but male fruit flies harass her so much, according to a new study, that she lays fewer eggs than normal. And that, researchers say, could be bad for the evolution of the entire species. When it comes to choosing a mating partner, females are usually the more picky sex. Female peacocks like the boys with the most colorful feathers, for example, and female deer go for big antlers. In the fruit fly world, however, males are the choosy ones. They prefer fatter females--they dance around them and constantly try to mate with them--probably because these females lay more eggs. Evolutionary biologist Tristan Long of the University of California, Santa Barbara, and colleagues wondered if all of this attention was bad for the females. The team sorted female fruit flies by knocking them out with carbon dioxide and sifting them through a series of sieves, each with holes a little smaller than the level above. In some experiments, males were given a choice between large-bodied females and randomly chosen females of all sizes; in others, they chose between small-bodied females and randomly chosen females. In still others, males were put in vials with all large females or all small females. When placed in vials with females of various sizes, the guys swarmed the largest females. "The males will court, they'll put their wings out and dance around, and they'll interfere with female foraging" by chasing them around while they're trying to eat, says Long. Eventually, the females gave in and mated many more times with the aggressive males than they needed to. (One time provides plenty of sperm.) "She's not mating because she needs sperm; she's probably mating because she's being worn down by this ongoing courtship," says Long. © 2009 American Association for the Advancement of Science.

Keyword: Sexual Behavior
Link ID: 13557 - Posted: 06.24.2010

Children with poor reading skills who underwent an intensive, six-month training program to improve their reading ability showed increased connectivity in a particular brain region, in addition to making significant gains in reading, according to a study funded in part by the National Institute of Mental Health (NIMH). The study was published in the Dec. 10, 2009, issue of Neuron. "We have known that behavioral training can enhance brain function." said NIMH Director Thomas R. Insel, M.D. "The exciting breakthrough here is detecting changes in brain connectivity with behavioral treatment. This finding with reading deficits suggests an exciting new approach to be tested in the treatment of mental disorders, which increasingly appear to be due to problems in specific brain circuits." For the study, Timothy Keller, Ph.D., and Marcel Just, Ph.D., both of Carnegie Mellon University, randomly assigned 35 poor readers ages 8–12, to an intensive, remedial reading program, and 12 to a control group that received normal classroom instruction. For comparison, the researchers also included 25 children of similar age who were rated as average or above-average readers by their teachers. The average readers also received only normal classroom instruction. Four remedial reading programs were offered, but few differences in reading improvements were seen among them. As such, results for participants in these programs were evaluated as a group. All of the programs were given over a six month schooling period, for five days a week in 50-minute sessions (100 hours total), with three students per teacher. The focus of these programs was improving readers’ ability to decode unfamiliar words.

Keyword: Dyslexia; Learning & Memory
Link ID: 13556 - Posted: 06.24.2010

By Adam Waytz Nobel Laureate economist, John Harsanyi, said that “apart from economic payoffs, social status seems to be the most important incentive and motivating force of social behavior.” The more noticeable status disparities are, the more concerned with status people become, and the differences between the haves and have-nots have been extremely pronounced during the economic recession of recent years. Barack Obama campaigned directly on the issue of the “dwindling middle class” during his 2008 presidential run and appointed vice-president Joe Biden to lead a middle class task force specifically to bolster this demographic. Despite some recent economic improvement, Senator Bernie Sanders of Vermont just two months ago cautioned that “the reality is that the middle class today in this country is in desperate shape and the gap between the very very wealthy and everyone else is going to grow wider.” Concerns about status likely will not be leaving the public consciousness any time soon. Of course, status differences are not simply relevant to economic standing, but they appear to be on our minds at all times. As renowned neuroscientist, Michael Gazzaniga, has noted, “When you get up in the morning, you do not think about triangles and squares and these similes that psychologists have been using for the past 100 years. You think about status. You think about where you are in relation to your peers.” Between CEO and employee, quarterback and wide receiver, husband and wife, status looms large. Recent work by social scientists has tackled the topic, elucidating behavioral differences between low-status and high-status individuals, and the methods by which those at the bottom of the totem pole are most successful at climbing to the top. © 1996-2009 Scientific American Inc.

Keyword: Aggression; Emotions
Link ID: 13555 - Posted: 06.24.2010

By Virginia Morell After a massive earthquake struck the Sichuan Province of China last year, troops and rescue workers brought in dogs to sift through the rubble. With a scent sensitivity many thousands of times greater than our own, the canines located numerous survivors--even those buried under thick debris for days. Now researchers think that they have figured out a key reason why dogs are such superior sniffers. The study could be useful in building odor-sensitive, artificial-nose machines. Scientists have known since the 1950s that dogs and other keen-scented mammals such as rats and rabbits have a specialized anatomical structure in their nasal cavity. Called the olfactory recess, it's a large maze of highly convoluted airways that humans and all other primates lack. In dogs, the recess lies right behind the eyes and takes up almost half of the interior of the nose. Scientists knew that something about the structure allows dogs to sniff odors invisible to humans. "But no one had looked at how air and odors actually flow inside" a dog's nose to reach that recess, says Brent Craven, a mechanical engineer at Pennsylvania State University, University Park. So Craven and his colleagues created a computer model of a canine nose. First, they scanned the nasal airway of a mixed-breed cadaver with high-resolution magnetic resonance imaging. "We then had to make our model simulate how dogs sniff," says Craven. But because that skill had also never been studied (although it has been in humans and rats), the researchers outfitted seven dogs, including a Pomeranian and a Labrador retriever, with a special muzzle. The device measured their rate of sniffing as they smelled things such as spoonfuls of peanut butter and tuna. Despite the wide range of sizes and weights, "all the dogs sniffed at about the same frequency, five times per second," says Craven. That's the same rate at which they pant. But "we knew they were sniffing and not simply breathing," says Craven, because high-speed videos showed "their nostrils flaring, which happens when they're sniffing, not when they're breathing." The team also mapped the flow of air into the dogs' noses as they sniffed, enabling them to calculate the nostrils' aerodynamic reach. © 2009 American Association for the Advancement of Science.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 13554 - Posted: 06.24.2010

By Michael Torrice We often think of memories like Polaroid snapshots, images frozen in time. But they're more like the fluid, melting pocket watches of Salvador Dali's painting The Persistence of Memory. Now scientists have developed a method that takes advantage of memory's malleability to block specific fear memories, which could someday lead to new therapies for anxiety disorders and phobias. Each time you recall the ice cream cake and clown from your fifth birthday party, the memory is subject to change. Information about the color of the clown's polka-dotted suit, for example, becomes "unfrozen" and could change from red to blue. This process is called reconsolidation, and scientists have blocked scary memories in rats--such as the association between a specific tone and a painful shock--during reconsolidation with drugs. Unfortunately, these drugs stop protein synthesis in the brain, which would lead to terrible side effects in people. A different approach to diminishing fear is called extinction training. In experiments with rats, scientists keep playing the ominous tone without a shock, and over time, the animals stop getting scared by the tone. Therapists use a similar method called exposure therapy to help people overcome debilitating fears, such as claustrophobia. But these methods aren't as long-lasting as the dangerous drugs. Earlier this year, scientists reported a happy compromise that worked in rats. They timed extinction training to when the rats' brains were reconsolidating the fearful tone memory, erasing that memory in the process. © 2009 American Association for the Advancement of Science.

Keyword: Learning & Memory; Emotions
Link ID: 13553 - Posted: 06.24.2010

By Josh Clark Physical and chemical changes in the body caused by abuse early in life can be passed down from mother to child, a recent study shows. The research by behavioral scientists at Emory University in Atlanta was based on studies that show how early life stress (ELS), such as physical and emotional abuse and neglect, leads to observable changes in the brain's hypothalamic-pituitary-adrenal (HPA) axis. This system, which is responsible for controlling the "fight or flight" response in humans, can be physically altered by abuse. While these changes can happen when abuse occurs at any point in life, the Emory study shows that abuse during pre-teen and adolescent years are most damaging, resulting in mood and anxiety disorders like Post Traumatic Stress Disorder (PTSD) and depression. What's more, the functional and physical changes caused by ELS can be passed along from female victims to their children. One of these means of transmission is through epigenetic changes. Epigenetics is a new field of study that examines how the function of DNA can change without any change to the DNA sequence itself. Through a process known as methylation, protein tags that enhance or thwart the function of a gene can be attached to an individual's DNA. © 2009 Discovery Communications,

Keyword: Stress; Development of the Brain
Link ID: 13552 - Posted: 06.24.2010

By Bruce Bower Medications frequently prescribed for depression may not lighten a person’s mood until they brighten his or her personality. A new study suggests that the antidepressant medication paroxetine, or Paxil, fights depression most effectively when it first modifies two personality traits that predispose people to this mood disorder. The two traits, high neuroticism and low extraversion, have already been linked to depression. Depressed patients taking Paxil reported much greater change in these traits, as assessed via scores on personality tests, than patients given placebo pills. The difference was notable even after accounting for the extent to which each treatment diminished standard measures of depression, says psychologist Tony Tang of Northwestern University in Evanston, Ill. Patients who experienced especially pronounced personality change during four months of Paxil treatment displayed a particularly low depression relapse rate over the next year of treatment, Tang’s team reports in the December Archives of General Psychiatry. “We propose that modern antidepressants work partly by correcting the long-term personality risk factors for depression,” Tang says. Like many other researchers and clinicians, Tang’s group initially suspected that personality changes observed during treatment with SSRIs (short for selective serotonin reuptake inhibitors) such as Paxil occur as a result of alleviating depression. But the new findings suggest that Paxil exerts an independent effect on personality that contributes to the lessening of depression. © Society for Science & the Public 2000 - 2009

Keyword: Depression
Link ID: 13551 - Posted: 06.24.2010

By Chris Tachibana Ron Brix’s longtime job as a computer systems developer for Wrigley, the gum and candy maker, required intense attention to detail, single-minded focus and a willingness to work on something repetitively until perfect. The secret he credits to his success? Autism. Brix, age 54, was diagnosed in 2001 with Asperger Syndrome, a form of autism often marked by the exact traits that help make him an ideal employee. "My career would not have existed at all without the autism," says Brix. The developmental condition, which strikes about 1 in 150 U.S. children, is considered a "spectrum disorder" because it affects people in many different ways to varying degrees, from mild social troubles to a severe inability to communicate. It's often seen as a heartbreaking diagnosis, but now some revolutionary companies see autism as something else: a resource. A quiet movement is growing around the globe to help transform the unique attributes of high-functioning autistic adults into sought-after job skills. In Denmark, the company Specialisterne (the name means "the specialists"), trains people with autism as specially skilled employees who are sent out as hourly consultants to companies to do data entry, assembly work and other jobs that many workers would find tedious and repetitive. Founded in 2004 by businessman Thorkil Sonne, the father of an autistic son, the company has 50 employees, 75 percent of whom are autistic. © 2009 msnbc.com.

Keyword: Autism
Link ID: 13550 - Posted: 06.24.2010

Alison Abbott The popular idea that testosterone always makes people more aggressive has been debunked by researchers. A team based in Switzerland has shown that the hormone can make people behave more fairly in an effort to defend their social status. Ernst Fehr, an experimental economist at the University of Zurich, and his colleagues used the 'ultimatum bargaining' game to test how testosterone would affect behaviour in a group of 121 women. Counter-intuitively, women who were given testosterone bargained more fairly. But the idea that testosterone causes aggression in humans, as it clearly does in rodents, is so firmly ingrained in the human psyche that women who believed they had been given testosterone — whether or not they had — bargained much less fairly. Women, not men, were tested because they have less variable 'baseline' blood testosterone levels. The study is published in Nature1. "It is a folk hypothesis that testosterone causes aggression," says Fehr. "But human society is more complex than this." Fair play Several studies in humans have shown positive correlations between high blood testosterone levels and confrontational behaviour. But it has been hard to determine experimentally whether the aggression is caused by testosterone or is instead a consequence of a challenge to a person's social status. The ultimatum game makes it possible to distinguish between these possibilities. © 2009 Nature Publishing Group

Keyword: Hormones & Behavior; Aggression
Link ID: 13549 - Posted: 06.24.2010

by Jessica Hamzelou A diet of chicken, fish and protein shakes might do wonders for people with brain injuries. Akiva Cohen of the University of Pennsylvania in Philadelphia and his colleagues mimicked brain injury in mice by injecting fluid through a hole drilled in their skull. After seven days, the brain-injured mice had much lower levels of three branched-chain amino acids (BCAAs), leucine, isoleucine and valine, compared with control mice. These are found in protein-rich food and are known for their ability to build muscle. The team then fed another set of brain-injured mice either plain water or water enriched with BCAAs. Five days later, those that had taken BCAAs had normal levels of the amino acids and performed better on a learning task. Excitation disturbance Cohen's team reckon they might have figured out how the BCAAs are having this effect. In the hippocampus of a person with a brain injury, the delicate balance of neuronal excitation and inhibition is disturbed, says Cohen. The BCAAs may help restore the balance by making more neurotransmitters, he suggests. The findings complement observations made by a group of Italian biochemists last year. Simona Viglio of the University of Pavia and colleagues found that minimally conscious patients who were given BCAAs intravenously improved in their "feeding, grooming and toileting" abilities. © Copyright Reed Business Information Ltd.

Keyword: Brain Injury/Concussion
Link ID: 13548 - Posted: 06.24.2010