John Krakauer Many things stimulate our brains' reward centers, among them, coordinated movements. Consider the thrill some get from watching choreographed fight or car chase scenes in action movies. What about the enjoyment spectators get when watching sports or actually riding on a roller coaster or in a fast car? Scientists aren't sure why we like movement so much, but there's certainly a lot of anecdotal evidence to suggest we get a pretty big kick out of it. Maybe synchronizing music, which many studies have shown is pleasing to both the ear and brain, and movement—in essence, dance—may constitute a pleasure double play. Music is known to stimulate pleasure and reward areas like the orbitofrontal cortex, located directly behind one's eyes, as well as a midbrain region called the ventral striatum. In particular, the amount of activation in these areas matches up with how much we enjoy the tunes. In addition, music activates the cerebellum, at the base of the brain, which is involved in the coordination and timing of movement. So, why is dance pleasurable? First, people speculate that music was created through rhythmic movement—think: tapping your foot. Second, some reward-related areas in the brain are connected with motor areas. Third, mounting evidence suggests that we are sensitive and attuned to the movements of others' bodies, because similar brain regions are activated when certain movements are both made and observed. For example, the motor regions of professional dancers' brains show more activation when they watch other dancers compared with people who don't dance.

Keyword: Hearing
Link ID: 12082 - Posted: 06.24.2010

By Tina Hesman Saey Researchers led by Carl Cotman and Nicole Berchtold at the University of California, Irvine, find that the activity of genes in men’s brains begins to change earlier than it does in women’s brains. The types of genes that change with age also differ between the sexes. The study, which appears online September 22 in the Proceedings of the National Academy of Sciences, also found that in both genders, each part of the brain examined had its own pattern of aging. “This is a very interesting study in what is, curiously, an under-studied area, normal aging,” says Etienne Sibille, a neuroscientist at the University of Pittsburgh, who was not involved in the study. “You have a combination of expected and surprises in each finding.” For instance, the fact that men and women’s brains age differently could be predicted based on women’s increased longevity, but the type and scope of the differences were unexpected, he says. Cotman and Berchtold and their colleagues collected brains from people who had died of various causes between ages 20 and 99. The researchers isolated messenger RNA, or mRNA, from the people’s brains. Messenger RNA is a courier molecule that carries instructions encoded in genes to the cellular machinery that will build proteins using those instructions. Genes that produce higher levels of mRNA are more active. © Society for Science & the Public 2000 - 2008

Keyword: Sexual Behavior; Alzheimers
Link ID: 12081 - Posted: 06.24.2010

Eighteen-month-old Valentina babbles earnestly to her dad Willie Matista at the Infancy Studies Laboratory at Rutgers in Newark. Valentina is progressing normally for her age and Matista says he “gets the picture” even if he doesn’t always know exactly what she is saying. But not all kids show this kind of progress. The Matistas have been volunteering to participate in neuroscientist April Benasich’s at the Rutgers Center for the Neurosciences since Valentina was 3-months-old. Benasich is trying to tease out why some children’s language abilities are impaired and others are on track. She likes to say she’s “eavesdropping” on what is going on in the brains of children while they are in this stage of rapid development. Her most recent study found a direct relationship between one type of brain wave and a toddler’s language ability. “We saw these really, really strong correlations to language and to cognitive outcomes and we were surprised because we thought if we saw anything it would be a subtle effect,” says Benasich. She and her team put soft sensor caps on toddlers aged 16 to 36 months that record their brain waves as they rest quietly in their parents’ laps. They analyzed these brain wave tests or electroencephalograms (EEGs), and looked specifically at a type of brain wave called a “gamma wave.” In adults, it’s thought to allow different areas of the brain to talk to each other more easily, but not much is known about gamma waves in toddlers. ©2008 ScienCentral

Keyword: Language; Development of the Brain
Link ID: 12080 - Posted: 06.24.2010

By Nathan Seppa Use of clot-busting drugs as long as 4 ˝ hours after an event pays dividends later Emergency room physicians can deliver clot-busting treatments to a wider range of stroke patients than previously thought, European researchers report in the Sept. 25 New England Journal of Medicine. The finding could change the way stroke is treated and increase ER doctors’ ability to prevent some cases of disability caused by strokes, scientists say. Most strokes result when a blood clot lodges in the brain, blocking blood flow to other parts of the organ. A powerful drug called tPA, or tissue plasminogen activator, can dissolve these clots. But medical dogma holds that it must be given within three hours of a stroke’s onset. Beyond that, the thinking goes, the bulk of the brain damage is done and adding the risk of internal bleeding that accompanies clot-busters seems unwise. The new study extends that window of effective tPA treatment by 90 minutes, to 4 ˝ hours. This precious extra time to dissolve a clot and restore blood flow to a starving portion of brain could benefit tens of thousands of stroke patients in the United States each year, says study coauthor Werner Hacke, a neurologist at the University of Heidelberg in Germany. © Society for Science & the Public 2000 - 2008

Keyword: Stroke
Link ID: 12079 - Posted: 06.24.2010

Parents of children with ADHD should be trained to help their children cope, and Ritalin should only be prescribed as a last resort, a health watchdog in Britain said Wednesday. The drug shouldn't be used in children under five, and should be prescribed for older children only when they have severe attention deficit hyperactivity disorder, the National Institute for Health and Clinical Excellence said in its guidelines for parents and doctors. Treatment with Ritalin — a brand name for the pharmaceutical methylphenidate — or other drugs "should be reserved for those with severe symptoms and impairment," the guidelines say. Symptoms of ADHD can include a short attention span, a low level of organization, excessive talking, aggressive gestures and irritability. It affects an estimated five to 12 per cent of Canadian children. When drugs for the disorder are prescribed, it should be along with psychological therapy and support for the child to develop problem solving, listening, coping and peer relationship skills, the group said. The guidelines also say parent training and education programs should be offered as a first-line treatment for ADHD in both preschool and school-aged children. © CBC 2008

Keyword: ADHD
Link ID: 12078 - Posted: 06.24.2010

By Yoshiaki Kikuchi and Madoka Noriuchi It’s probably not surprising that mothers excel at recognizing and interpreting the moods and emotions of their infants. Although infants can’t speak, mothers seem to know what their babies are thinking: they smile when their baby smiles and they frown when their baby is upset. Research suggests that the mother’s ability to understand the needs of her infant is very important for establishing a secure mother-infant relationship. However, the neural mechanisms that underlie these behaviors are poorly understood. Such knowledge is crucial for understanding normal as well as abusive and neglectful mothering. In recent years, several studies have been carried out using functional magnetic resonance imaging (fMRI) to better understand how a mother’s brain responds to her own child’s cues. The most recent, led by neuroscientist Lane Strathearn and colleagues at Baylor College of Medicine, investigated what happens inside the brain of a mother when she looks at the facial expressions of her own infant. In the study, 28 first-time mothers were shown pictures of their seven-month old child that they had never seen before. (The pictures were taken when the mother was not present.) The pictures spanned a wide range of human emotion and included images of the child making happy, sad or neutral faces. These pictures were then matched with images of an unknown infant. The central finding was that seeing the happy face of the mother’s own infant activated all of the key areas in the brain associated with reward processing. These regions include the ventral tegmental area, substantia nigra and the striatum. This finding suggests that for mothers the sight of their smiling baby is a potent reward and represents a uniquely pleasurable experience. Furthermore, this neural response was graded, so that happy faces led to more activation than neutral faces. Sad faces generated the least activation. In other words, the response of mothers in their reward areas seemed to directly mirror the emotions the infant displayed. © 1996-2008 Scientific American Inc

Keyword: Development of the Brain; Sexual Behavior
Link ID: 12077 - Posted: 06.24.2010

By ALAN SCHWARZ N.F.L. players are lionized every Sunday for giving their bodies to the sport. Now, some retired players are planning to literally give their brains to a new center at Boston University’s School of Medicine devoted to studying the long-term effects of concussions. A dozen athletes, including six N.F.L. players and a former United States women’s soccer player, have agreed to donate their brains after their deaths to the Center for the Study of Traumatic Encephalopathy. On Thursday, the center will announce that a fifth deceased N.F.L. player, the former Houston Oilers linebacker John Grimsley, was found to have brain damage commonly associated with boxers. The former New England Patriots linebacker Ted Johnson, one of the players who has agreed to donate his brain, said he hoped the center would help clarify the issue of concussions’ long-term effects, which have been tied to cognitive impairment and depression in several published studies. The N.F.L. says that, in regard to its players, the long-term effects of concussions are uncertain. “I shouldn’t have to prove to anybody that there’s something wrong with me,” said Johnson, 35, whose neurologist has said multiple concussions from 2002 through his 2005 retirement resulted in permanent and degenerative problems with memory and depression. Copyright 2008 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 12076 - Posted: 06.24.2010

By Gero Miesenböck In 1937 the great neuroscientist Sir Charles Scott Sherrington of the University of Oxford laid out what would become a classic description of the brain at work. He imagined points of light signaling the activity of nerve cells and their connections. During deep sleep, he proposed, only a few remote parts of the brain would twinkle, giving the organ the appearance of a starry night sky. But at awakening, “it is as if the Milky Way entered upon some cosmic dance,” Sherrington reflected. “Swiftly the head-mass becomes an enchanted loom where millions of flashing shuttles weave a dissolving pattern, always a meaningful pattern though never an abiding one; a shifting harmony of subpatterns.” Although Sherrington probably did not realize it at the time, his poetic metaphor contained an important scientific idea: that of the brain revealing its inner workings optically. Understanding how neurons work together to generate thoughts and behavior remains one of the most difficult open problems in all of biology, largely because scientists generally cannot see whole neural circuits in action. The standard approach of probing one or two neurons with electrodes reveals only tiny fragments of a much bigger puzzle, with too many pieces missing to guess the full picture. But if one could watch neurons communicate, one might be able to deduce how brain circuits are laid out and how they function. This alluring notion has inspired neuroscientists to attempt to realize Sherrington’s vision. © 1996-2008 Scientific American Inc

Keyword: Brain imaging
Link ID: 12075 - Posted: 06.24.2010

Peter Aldhous ANTIDEPRESSANTS taken by millions of men could be impairing their fertility by causing damage to the DNA in their sperm. In 2006, Peter Schlegel and Cigdem Tanrikut of the Cornell Medical Center in New York City reported that two men had developed low counts of healthy sperm after taking two different selective serotonin-reuptake inhibitors (SSRIs), the most commonly prescribed class of antidepressant. Now Schlegel's team has given 35 healthy men doses of a third SSRI called paroxetine, sold as Seroxat or Paxil, over five weeks, and examined their sperm before treatment and four weeks in. Superficially, the men's sperm seemed healthy - amounts of sperm and semen, and the shape and motility of sperm, were all normal. But when the team looked at DNA fragmentation in the sperm, using the TUNEL method, a worrying picture emerged. On average, the proportion of sperm cells with fragmented DNA rose from 13.8 per cent before taking paroxetine to 30.3 per cent after just four weeks. Similar levels of sperm DNA damage have been linked to problems with embryo viability. For example, in couples undergoing IVF, studies have found that where the man has more sperm with damaged DNA, fewer embryos form and those that do are less likely to implant successfully into the woman's uterus. As a result, fertility specialists regard a fraction of 30 per cent of sperm with DNA damage as being "clinically significant", says Douglas Carrell, a specialist in male infertility at the University of Utah in Salt Lake City. © Copyright Reed Business Information Ltd.

Keyword: Depression
Link ID: 12074 - Posted: 06.24.2010

Researchers in Gothenburg studying the connection between alcoholism and the hormone ghrelin have found that a single genetic cause may lie behind several forms of dependency. “It feels exciting and totally new,” said Elisabeth Jerlhag, one of the researchers from the Institute of Neuroscience and Physiology at the University of Gothenburg’s Sahlgrenska Academy, to the Göteborgs-Posten (GP) newspaper. The hormone ghrelin, found primarily in the stomach as well as the brain, is well-known for its role in controlling people’s appetites. Previous research on ghrelin has focused on its role in dietary-related diseases such diabetes and obesity. But the Gothenburg team’s research points to a broader role for the hormone when it comes to the reward systems in people’s brains associated with various types of addiction. After reviewing previous studies which indicated that alcoholics were found to have higher levels of ghrelin in their blood, Jerlhag and the rest of the team led by Professor Jörgen Engel then examined the genes of 417 people, 138 of whom had sought medical treatment for high alcohol consumption. “We found variations in the gene for ghrelin which had a strong connection both with high alcohol intake and with obesity,” said Sara Landgren, another researcher in the group, to GP.

Keyword: Drug Abuse; Obesity
Link ID: 12073 - Posted: 06.24.2010

US scientists have claimed success using gene therapy to try to reverse a severe inherited sight disorder. They injected material containing a corrective gene into the eyes of three patients with Leber congenital amaurosis (LCA). The journal Proceedings of the National Academy of Sciences reports all three showed signs of "significant" improvement in their vision. UK researchers carried out a similar procedure on three patients last year. They believe the method could be ready for use within two years to treat people suffering from some inherited diseases of the retina, which affect 20,000 people in Britain. Within three years, they believe it could be ready for testing on people who suffer age related macular degeneration, a condition that affects 500,000 Britons. Gene therapy works on a simple principle - to replace a malfunctioning gene, and restore function to a part of the body affected by a genetic disorder. In practice, however, it has proved very difficult to find ways to introduce the new gene copies in the correct tissues, and experiments in animals have had mixed results. In the eye, however, gene therapy has shown more promise. LCA affects approximately one in 80,000 people, causing progressively worsening vision, often starting in the first few years of life. It is responsible for one in 10 severe sight disorders in children. A fault in the RPE65 gene is to blame, and the gene therapy injects working copies of the gene into the back of the eye. Just 30 days after the treatment was delivered into one eye of each of the three young adults involved in the US study, the improvements could be measured. (C)BBC

Keyword: Vision; Genes & Behavior
Link ID: 12072 - Posted: 09.23.2008

by Kathleen McAuliffe Early on in the Iraq War, clinical psychologist Albert “Skip” Rizzo stumbled upon the video game Full Spectrum Warrior and determined to make a therapeutic tool out of it. Rizzo, a University of Southern California professor who had designed virtual reality tools to measure attention deficits in children, realized that thousands of soldiers would come back from the Middle East with post-traumatic stress disorder. Since 2005 the program he developed, Virtual Iraq, has had great success in treating the returning troops. What is the greatest challenge in your field today? To help people plagued by nightmares, flashbacks, and relentless stress related to a traumatic episode—being raped, narrowly escaping the collapse of the Twin Towers, witnessing a buddy die on the battlefield. Traditionally the best treatment for post-traumatic stress disorder [PTSD] is to have the person relive the trauma using his or her imagination. Repeated exposure to the horror can desensitize individuals and help them stay calm enough to reprocess what happened and get beyond it. How does virtual reality address this problem? We immerse the individual in a virtual world to allow him or her to vividly reexperience the episode in a safe and controlled way. In Virtual Iraq, a soldier with PTSD recounts what happened, and a therapist seated before a computer then creates an environment that captures the essential elements of the episode. Say the soldier was driving in a Humvee convoy when the vehicle in front of him blew up. By donning special goggles, he can see a reenactment: To the left he sees a desert landscape; straight ahead, the Humvee. The simulation is done on a vibrating platform, so he feels the humming of the vehicle’s motor or the rumble of the exploding IED [improvised explosive device].

Keyword: Stress
Link ID: 12071 - Posted: 06.24.2010

By Lisa Rein This was supposed to be my exciting new life in Washington. I had been hired by one of the nation's great newspapers. I was setting up a cute apartment in Dupont Circle. And yet my body was sending me a signal that all was not well: I was waking every morning with a throbbing pain in my jaw. A dentist took one look into my sore mouth and pronounced me a victim of an affliction common among Type A people who move to Washington for stressful jobs. Bruxism. I was grinding my teeth at night. It was so bad that a diagnostic test, which involved sliding my teeth from side to side on a thin sheet resembling carbon paper, turned up several molars that were practically flattened and one that was starting to crack. At 35, I was losing my teeth. It turns out that we are a nation of bruxers . About 10 percent of adults grind regularly, although dentists say that half of the population, including children, gnash at some point in their lives. But as many as half of the serious grinders don't seek treatment, either because they don't see a dentist or because the habit doesn't cause them pain. Eventually they'll wear right through their teeth, though, and that will be really painful -- as well as costly. © Copyright 1996-2008 The Washington Post Company

Keyword: Sleep; Pain & Touch
Link ID: 12070 - Posted: 06.24.2010

By Dan Vergano, USA TODAY Images that purport to show — in living color — the parts of the brain that generate such virtues as compassion, fairness and wisdom are invading turf that was once reserved for philosophers, theologians and psychologists. From morality to math, a revolution in "functional" magnetic resonance imaging (fMRI), which observes brain blood flow, is being used by researchers to pinpoint the pieces of the brain that people rely on to think and feel. So, what's the problem? "A lot of these claims are just crazy," says neurophysiologist Nikos Logothetis of Germany's Max Planck Institute for Biological Cybernetics. "There is a fundamental mismatch between what these images are showing and what cognitive scientists are claiming for these studies." Here's a sampling of fMRI tests from recent news releases: •University of Florida researchers asked 12 volunteers to have an fMRI while watching ads for Coca-Cola, Evian and Gatorade "to find out how people really feel about something." •University of Wisconsin researchers reported that when 16 Tibetan monks meditated inside an fMRI machine, the images showed "brain circuits used to detect emotions and feelings were dramatically changed in subjects who had extensive experience practicing compassion meditation." Copyright 2008 USA TODAY, a division of Gannett Co. Inc.

Keyword: Brain imaging
Link ID: 12069 - Posted: 06.24.2010

Aria Pearson Wasps can remember each other after a busy week apart, according to new research. It's a level of social memory never seen before in insects, which were long thought to be too small-brained for such a feat. Queens of the paper wasp, Polistes fuscatus, form cooperative nests after fighting to establish a dominance hierarchy. When big-brained vertebrates like primates fight to establish dominance, they benefit from their ability to remember previous adversaries. But insects, even those with complex social colonies, were thought to lack that kind of individual social intelligence. Michael Sheehan and Elizabeth Tibbetts at the University of Michigan in Ann Arbor, tested that idea. Tibbetts knew that wasps can recognise individuals based on colour patterns on their faces. The next step was to see if they could remember individuals over a period of time in which they were distracted by other social interactions. Buzz off, stranger The researchers exposed female wasps to a new individual and then placed them in separate cages along with 10 other wasps. After one week, the females acted much more aggressively when placed with another new individual than when placed with the wasp they had met before. © Copyright Reed Business Information Ltd

Keyword: Learning & Memory; Evolution
Link ID: 12068 - Posted: 06.24.2010

by Charles Barber A team of American researchers attracted national attention last year when they announced results of a study that, they said, reveal key factors that will influence how swing voters cast their ballots in the upcoming presidential election. The researchers didn’t gain these miraculous insights by polling their subjects. They scanned their brains. Theirs was just the latest in a lengthening skein of studies that use new brain-scan technology to plumb the mysteries of the American political mind. But politics is just the beginning. It’s hard to pick up a newspaper without reading some newly minted neuroscientific explanation for complex human phenomena, from schizophrenia to substance abuse to ­homosexuality. The new neuroscience has emerged from the last two decades of formidable progress in brain science, psychopharmacology, and brain imaging, bringing together research related to the human nervous system in fields as diverse as genetics and computer science. It has flowered into one of the hottest fields in academia, where almost anything “neuro” now generates excitement, along with neologisms—neuroeconomics, neurophilosophy, neuromarketing. The torrent of money flowing into the field can only be described in superlatives—hundreds of millions of dollars for efforts such as Princeton’s Center for the Study of Brain, Mind, and Behavior and MIT’s McGovern Institute for Brain Research. Psychiatrists have been in the forefront of the transformation, eagerly shrugging off the vestiges of “talk therapy” for the bold new paradigms of neuroscience. By the late 1980s, academic psychiatrists were beginning literally to reinvent parts of the discipline, hanging out new signs saying Department of Neuropsychiatry in some medical schools. A similar transformation has occurred in academic psychology. Copyright 2008, The Woodrow Wilson International Center for Scholars.

Keyword: Depression; Schizophrenia
Link ID: 12067 - Posted: 06.24.2010

Jessica Griggs Can smells sweeten your dreams? Certain aromas, such as lavender, are known to have soporific effects, but once you’re asleep, can smells influence what you dream about? To find out, Boris Stuck of University Hospital Mannheim, Germany, exposed 15 sleeping volunteers to chemicals that mimicked the smell of either rotten eggs or roses. "Most everyday smells have two components: the actual smell and a component that irritates your nose," says Stuck. "By exposing the patients to chemicals chosen to only incorporate the smelly component, we were able to stimulate them with really high doses of the smell without them waking up." Stuck's team waited until their subjects had entered the REM phase of sleep, the stage at which most dreams occur, and then exposed them to a high dose of smelly air for 10 seconds before waking them up one minute later. The volunteers were then quizzed about the content of their dreams and asked how it made them feel. Rose-tinted dreams All subjects reported a positive dream experience when stimulated by the rose smell, and most experienced the opposite when exposed to the rotten eggs. Stuck says the smells influence the "emotional colouration" of the dream. The team are now looking to recruit people who suffer from nightmares to see if exposure to smells can help make their dreams more pleasant. © Copyright Reed Business Information Ltd

Keyword: Chemical Senses (Smell & Taste); Sleep
Link ID: 12066 - Posted: 06.24.2010

Heidi Ledford Microbes that call the intestines home help ward off type 1 diabetes in mice, researchers have found. The findings, published online today by Nature1, are the latest in a series of revelations about the impact that resident bacteria may have on health. Humans, mice and other animals are home to a complex community of trillions of microbes, mostly living harmlessly in their guts, their skin and elsewhere. In humans the effects of this 'microbiome' on metabolism and the immune system have been linked to obesity2 and inflammatory bowel disease3. Now type 1 diabetes, an autoimmune disease that affects the pancreas, can be added to the list. A link to the microbiome could provide an explanation for the rising rates of this disease, particularly in developed countries. For years, researchers have put forward possible explanations in terms of infection, lifestyle and environment: a particular virus infection, perhaps, or chemicals found in certain processed foods. "The problem is, we've never found out what that trigger is," says Denis Daneman, chairman of paediatrics at the Hospital for Sick Children in Toronto, who is currently investigating ways that diet may increase the risks. Over a decade ago, some researchers noted that a diabetes-prone strain of mouse is even more likely to develop the disease when it is grown in a sterile, microbe-free environment. The observation suggested that exposure to bacteria could somehow help stave off the disease. © 2008 Nature Publishing Group

Keyword: Obesity
Link ID: 12065 - Posted: 06.24.2010

By Michelle Roberts A study has linked a small number of cases of cerebral palsy to antibiotics given to women in premature labour. The UK study found 35 cases of cerebral palsy in 769 children of women without early broken waters given antibiotics. This compared with 12 cases among 735 children of women not given the drugs. Advice is being sent to the study's 4,148 mothers and a helpline set up. Medical experts stressed pregnant women should not feel concerned about taking antibiotics to treat infections. The Oracle study was the largest trial in the world into premature labour and was set up to investigate whether giving antibiotics - which might tackle an underlying symptomless infection - to women with signs of premature labour would improve outcomes for babies. One in eight babies in the UK is born prematurely and prematurity is the leading cause of disability and of infant death in the first month after birth. In 2001, ORACLE found the antibiotic erythromycin had immediate benefits for women in premature labour (before 37 weeks gestation) whose waters had broken. It delayed onset of labour and reduced the risk of infections and breathing problems in babies. Erythromycin and the other antibiotic studied - co-amoxiclav - showed no benefit or harm for the women whose waters were still intact, however, and doctors were advised not to routinely prescribe them in such circumstances.

Keyword: Development of the Brain
Link ID: 12064 - Posted: 09.20.2008

by Becky McCall Cosmos Online LIVERPOOL, UK: Our memories of major past events can be surprisingly unreliable, says a new study of the July 2005 London bombings, which found that people can easily convince themselves they've seen things that never happened. "Some people think that our memories are like video recorders and that if you press play the memories come flooding back. It doesn't work like that at all and should not form the basis of legal decision making" said James Ost, a psychologist from the University of Portsmouth, England. Ost said that when DNA testing became available in the U.S. in the early 90s, 80 per cent of death row cases that were exonerated, were found to have been wrongly convicted on the strength of mistaken identity. His research demonstrates how this can happen. To investigate how reliable our memories are, he asked people in the U.K. and Sweden if they'd seen CCTV footage of the bus bombing in the city's Tavistock Square. Eighty-four per cent of U.K. respondents said that they had, compared to 50 per cent of Swedish participants, when in fact, no such footage exists. His research was presented last week at the British Association for the Advancement of Science (BA) Festival of Science, held in Liverpool, England.

Keyword: Learning & Memory
Link ID: 12063 - Posted: 09.20.2008