By Scicurious A week or so ago (hard to tell with holiday time as it is) Senator Tom Coburn (R-Oklahoma) released his 2011 “Wastebook”, a list of govt. funded projects that he and his staff consider to be a waste of money. I was of course dismayed to find several science projects make the list, including several funded by the NIH and of importance to public health. In particular, there was this: 23) Rockin’ Robins: Study Looks for Connections Between Cocaine and Risky Sex Habits of Quail – (KY) $175,587 What common sense suggests, science has confirmed over and over again: namely, that cocaine use is linked to increased risky sexual behavior. 137 Just to be sure, however, one federal agency thought it should test the hypothesis on a new subject: Japanese quail. The University of Kentucky received a grant of $181,406 in 2010 from the National Institute of Health to study how cocaine enhances the sex drive of Japanese quail. 138 In 2011, grant funding was extended and an additional $175,587 was provided for the study. 139 The total awarded to the project will be $356,933.140 Senator Coburn clearly thinks that because we already know that cocaine is bad and increases sexual promiscuity, it is no longer worth studying. I rather strongly disagree with this, and so I’d like to use this post to talk a bit about WHY we still need to study the effects cocaine and addictive drugs in general, why we need to study the effects on sexual behavior in particular, and why quail are a good choice. © 2011 Scientific American,

Keyword: Drug Abuse; Sexual Behavior
Link ID: 16200 - Posted: 12.31.2011

(Relaxnews) - Having to follow a restrictive diet that limits the consumption of foods like bread and pasta has been shown to cause depression, disordered eating and impaired quality of life in women suffering from celiac disease, says a new report that delves into the psychiatric impacts of leading a gluten-free lifestyle. In a study published in the December issue of Chronic Illness, researchers from Penn State University, Syracuse University and Drexel University analyzed the online answers of 177 American women who suffer from celiac disease, an autoimmune disorder triggered by gluten, a protein found in wheat, barley and rye-based products. Symptoms of the illness include abdominal pain, constipation, decreased appetite, diarrhea, nausea and vomiting. In their study, researchers found that women who adhered to strict gluten-free diets also reported higher rates of stress, depression, and body image issues compared to the general population. Where their study falls short, researchers say, is understanding what comes first: disordered eating or depression. Not only does celiac disease impose a slew of dietary restrictions, the illness also increases "psychosocial distress," said study co-author Josh Smyth of Penn State. "Going out to eat with friends or to a holiday potluck is a much different experience for these people because they have to be vigilant and monitor their diets," he said in a statement. "They may feel that they are a burden on a host or hostess. In many cases the only treatment option they are given is to manage their diets.” © 2011 NY Times Co.

Keyword: Depression
Link ID: 16199 - Posted: 12.31.2011

By Nick Bascom Superstar athletes are revered for their physical prowess, not for what goes on between their ears. And most postgame interviews do little to challenge the notion that athletes have more brawn than brains. But brainpower has a vital role in elite sports performance, recent research shows. “Brawn plays a part, but there’s a whole lot more to it than that,” says John Milton, a neuroscientist at the Claremont Colleges in California. Whether on the court, field or course, the body depends on the brain for direction. But the brain is a busy taskmaster, with duties beyond guiding motion, making it difficult to focus on that particular job. Like chess masters and virtuoso musicians, superior athletes are better than novices at turning on just the parts of the brain relevant to the desired task, Milton’s work reveals. “In professionals, the overall brain activation is much lower, but certain connections are enhanced,” he says. In other words, experts employ only the finely tuned neural regions that help enhance performance, without getting bogged down by extraneous information. Elite athletes’ ability to focus the brain might even explain their struggle to eloquently describe performance after the game. Like a starship captain diverting power from life support to bolster shields in a battle, professional athletes temporarily shut down the memory-forming regions of the brain so as to maximize activity in centers that guide movement. © Society for Science & the Public 2000 - 2011

Keyword: Biomechanics; Muscles
Link ID: 16198 - Posted: 12.31.2011

By Helen Briggs Health editor, BBC News website A diet rich in vitamins and fish may protect the brain from ageing while junk food has the opposite effect, research suggests. Elderly people with high blood levels of vitamins and omega 3 fatty acids had less brain shrinkage and better mental performance, a Neurology study found. Trans fats found in fast foods were linked to lower scores in tests and more shrinkage typical of Alzheimer's. A UK medical charity has called for more work into diet and dementia risk. The best current advice is to eat a balanced diet with plenty of fruit and vegetables, not smoke, take regular exercise and keep blood pressure and cholesterol in check, said Alzheimer's Research UK. The research looked at nutrients in blood, rather than relying on questionnaires to assess a person's diet. US experts analysed blood samples from 104 healthy people with an average age of 87 who had few known risk factors for Alzheimer's. They found those who had more vitamin B, C, D and E in their blood performed better in tests of memory and thinking skills. People with high levels of omega 3 fatty acids - found mainly in fish - also had high scores. The poorest scores were found in people who had more trans fats in their blood. BBC © 2011

Keyword: Alzheimers
Link ID: 16197 - Posted: 12.31.2011

By TARA PARKER-POPE For 15 years, Joseph Proietto has been helping people lose weight. When these obese patients arrive at his weight-loss clinic in Australia, they are determined to slim down. And most of the time, he says, they do just that, sticking to the clinic’s program and dropping excess pounds. But then, almost without exception, the weight begins to creep back. In a matter of months or years, the entire effort has come undone, and the patient is fat again. “It has always seemed strange to me,” says Proietto, who is a physician at the University of Melbourne. “These are people who are very motivated to lose weight, who achieve weight loss most of the time without too much trouble and yet, inevitably, gradually, they regain the weight.” Anyone who has ever dieted knows that lost pounds often return, and most of us assume the reason is a lack of discipline or a failure of willpower. But Proietto suspected that there was more to it, and he decided to take a closer look at the biological state of the body after weight loss. Beginning in 2009, he and his team recruited 50 obese men and women. The men weighed an average of 233 pounds; the women weighed about 200 pounds. Although some people dropped out of the study, most of the patients stuck with the extreme low-calorie diet, which consisted of special shakes called Optifast and two cups of low-starch vegetables, totaling just 500 to 550 calories a day for eight weeks. Ten weeks in, the dieters lost an average of 30 pounds. At that point, the 34 patients who remained stopped dieting and began working to maintain the new lower weight. Nutritionists counseled them in person and by phone, promoting regular exercise and urging them to eat more vegetables and less fat. But despite the effort, they slowly began to put on weight. After a year, the patients already had regained an average of 11 of the pounds they struggled so hard to lose. They also reported feeling far more hungry and preoccupied with food than before they lost the weight. © 2011 The New York Times Company

Keyword: Obesity
Link ID: 16196 - Posted: 12.31.2011

(HealthDay News) -- New research suggests that in addition to the disabling lesions it's known to cause, multiple sclerosis also damages the part of the brain that affects thinking skills, motor function and the senses. "The thalamus is a central area that relates to the rest of the brain and acts as the 'post office,'" study co-author Khader Hasan, an associate professor at University of Texas Health Science Center at Houston, said in a university news release. "It also is an area that has the least amount of damage from lesions in the brain, but we see volume loss, so it appears other brain damage related to the disease is also occurring." Hasan and colleagues published their observations in a recent issue of the Journal of Neuroscience. The study authors noted that aging alone can bring about changes in the size of the thalamus region, resulting in some shrinkage after age 70. However, the research team wanted to see if multiple sclerosis (MS) -- which is often associated with the onset of dementia -- accelerates such structural shifts. The radiology researchers used cutting-edge MRI scanning equipment to analyze brain structure in 109 MS patients, compared to 255 healthy men and women. The result: MS patients had greater volume loss in the thalamus region than healthy patients, after accounting for age. And the greater the loss in thalamus volume, the more disabled the patient was, the investigators noted. © 2011 U.S.News & World Report LP

Keyword: Multiple Sclerosis; Brain imaging
Link ID: 16195 - Posted: 12.31.2011

By Jason Castro If you have never watched bees carefully, you are missing out. Look closely as they gently curl and uncoil their mouthparts around food, and you will sense that they are not just eating but enjoying their meal. Watch a bit more, and the hesitant flicks and sags of their antennae seem to convey some kind of emotion. Do those twitches signal annoyance? Or something like enthusiasm? Whether bees really experience any of these emotions is an open scientific question. It is also an important one, with implications for how we should treat not just bees but the great majority of animals. Recently studies by Melissa Bateson and her colleagues at Newcastle University in England have rekindled the debate over these issues by showing that honeybees may experience something akin to moods. Using simple behavioral tests, Bate­son’s team showed that honeybees under stress tend to be pessimistic. Other tests have demonstrated that monkeys, dogs and starlings all tend to react similarly under duress and likewise see the proverbial glass as half empty. Although this finding does not—and cannot—prove that bees experience humanlike emotions, it does give pause. We should take seriously the possibility that insects, too, have emotions. First, a little bit about bees. They are members of the diverse group of animals lacking backbones—indeed, more than 95 percent of all animal species are invertebrates. Despite the varied and often nuanced behaviors they can exhibit, invertebrates are sometimes regarded as life’s second string, a mindless and unfeeling band of alien critters. If that seems somewhat melodramatic, just consider our willingness to boil some of them alive. © 2011 Scientific American,

Keyword: Emotions; Evolution
Link ID: 16194 - Posted: 12.27.2011

by Jeff Hecht Tortoises aren’t noted for their speed but they are surprisingly quick-witted "IT ALL stems from Moses," says Anna Wilkinson. Moses is her pet red-footed tortoise and a bit of a celebrity in the science world. Why? First, he outsmarted rats in a maze. Then he was the inspiration for a new lab studying reptile intelligence and the evolutionary origins of cognition. Now he has helped Wilkinson win an Ig Nobel prize. Victory for slow and steady. This fruitful partnership began in 2004, after Wilkinson, now at the University of Lincoln, UK, started graduate school at the University of York, also in the UK. She was studying bird cognition but had earlier become fascinated by tortoises while employed in education and research at Flamingo Land zoo in North Yorkshire, UK. Although working with primates, she found herself drawn to the tortoise enclosure. Even when most of the group was basking in the sun, she recalls, at least one tortoise was exploring or feeding, and when a person walked in they all perked up, sensing that food was likely to follow. "They were always just fascinating," she says. So, a tortoise was the obvious choice as a pet. Moses's first big academic break came in 2006. Wilkinson was attending a lecture on how rats remember their paths through a maze, when she started thinking: "Moses can do that." Afterwards, she asked the lecturer, Geoffrey Hall, if anyone had tried putting tortoises in such mazes. A literature search indicated that reptiles in general have proved pretty dim when subjected to cognitive tests. Undeterred, Hall and Wilkinson decided to see what Moses was capable of. © Copyright Reed Business Information Ltd.

Keyword: Evolution; Learning & Memory
Link ID: 16193 - Posted: 12.27.2011

By DOUGLAS QUENQUA Tropical fish hobbyists will tell you their tanks are a source of relaxation, but recent research suggests the fish might disagree. Nearly 13 million American households contain a fish tank, and the average tank size is less than 10 gallons. Yet a study comparing the behavior of common freshwater fish in a variety of habitats found that those kept in such small tanks were considerably more aggressive than those in larger ones — more likely to fight, flare their gills and guard whatever tiny alcoves they could find. “In larger tanks, the fish were not in continuous eyesight of each other, and were swimming around checking everything out rather than beating the heck out of each other,” said the study’s author, Ronald G. Oldfield, a professor of biology at Case Western Reserve University. The fish in question were Midas, or “red devil” cichlids, a species popular among hobbyists for their brilliant colors and active swimming habits. Dr. Oldfield used only very young fish to eliminate aggressive behaviors associated with mating. Dr. Oldfield concedes that the emotional well-being of fish may not tug many heartstrings. “It’s probably not the end of the world,” he said in a telephone interview. Even the Humane Society, which routinely has commercials featuring slow-motion video of abused pets, does not offer guidelines for the treatment of pet fish. © 2011 The New York Times Company

Keyword: Aggression; Stress
Link ID: 16192 - Posted: 12.27.2011

by Jeff Warren What if we merged brains with other species? Would we have very different psychology? Or wordlessly swap intimate feelings? I'VE spent years thinking about consciousness and my current obsession is whether we can know anything about what it is like is to be a dog, a dolphin, or a bat. The most influential answer came from philosopher Thomas Nagel in his 1974 paper, "What is it like to be a bat?" Unlike some of the era's behaviourists, who saw animals as little more than automatons that respond to stimulus, Nagel didn't doubt bats had experience, that it was "like something" being a nimble, echo-locating mammal swooping through the night. But he doubted our ability to say anything true about it beyond projection or imagination. Nagel may be right, but for me the human-to-animal mind question is simply an extreme form of the human-to-human mind question: we can't know another's experience, but there are deep points of overlap we can expand. What follows is from a conversation with two of the smartest people I know in the field: Lori Marino, a comparative neuroanatomist at Emory University in Atlanta, Georgia, and Ben Goertzel, a mathematician, and a former research director of the Singularity Institute for Artificial Intelligence in San Francisco. JEFF: Imagine that in front of us are the disarticulated brains of a human, a dog and a dolphin. What might we learn by combining the pieces of the animals in unusual ways? LORI: Something similar is going on in Leipzig. For example, researchers inserted a human gene into a mouse brain, causing it to grow human-like neurons in the language area: the mouse's vocalisations were deeper. © Copyright Reed Business Information Ltd.

Keyword: Evolution; Attention
Link ID: 16191 - Posted: 12.27.2011

By LAURIE TARKAN Three years ago, Kristie Salerno Kent, a singer-songwriter, was standing in a security line at the airport on her way home from a gig when her legs went numb. “From the waist down, it felt as though I was trying to walk through a bowl of oatmeal,” said the 38-year-old musician, who has multiple sclerosis. She inched her way to a security officer, who called for a wheelchair and helped remove her shoes and belt to get her through security. Frightened and embarrassed, she was taken to her gate in a wheelchair. Three months later, she experienced another flare-up. While giving a live television interview about a short film she had made on living with M.S., she suddenly lost her ability to speak. “It was as if my mouth was packed with marbles,” she said. “I kept trying to say, ‘I’m sorry,’ to the reporter, but nothing came out that made sense.” The medication she was taking to prevent these attacks was losing its effect, so her doctor suggested she switch to Tysabri, one of the newer, more potent “disease-modifying drugs,” which reduce the severity and frequency of relapses. She also began taking Ampyra, which early last year became the first drug approved to treat any M.S. symptom. She hasn’t had a flare-up since. After decades of basic research on M.S., the last five years have brought a rapid rollout of new and sophisticated drugs that are changing how this disease is managed and offering patients new hope. © 2011 The New York Times Company

Keyword: Multiple Sclerosis
Link ID: 16190 - Posted: 12.27.2011

Allie Bidwell, Chronicle Staff Writer For most of his adult life, Michael Berg has suffered from sinus problems that led to strange reactions to the way he smelled and tasted things. Drinking a glass of wine or smoking a cigar, for example, would drastically reduce his sense of smell. He knew that alcohol and smoking could dull the senses, so he thought nothing of it. Then one day in 2005, his sense of smell completely vanished. "Literally one day we were having dinner, and I remember I couldn't smell or taste anything," Berg, 55, said. Experts estimate that about 2 percent of the U.S. population suffers from Berg's condition, a lack of smell known as anosmia. And research by neuroscientists at UC Berkeley provides hope of new therapies for those who have lost their sense of smell, whether due to aging, trauma or a viral infection. In the study published this month in the journal Neuron, the researchers - led by campus neurobiology Professor John Ngai - found a genetic trigger responsible for renewing smell sensors in the nose. That gene, known as p63, tells olfactory stem cells whether to replace themselves or to change into different types of cells. Under normal circumstances, Ngai said, there is a balance between the two outcomes. © 2011 Hearst Communications Inc.

Keyword: Chemical Senses (Smell & Taste); Neurogenesis
Link ID: 16189 - Posted: 12.27.2011

By KAREN BARROW Imagine being unable to recognize your children or your closest friend. You can see their faces perfectly fine, but if you passed them on the street you wouldn’t be able to place their unique eyes, nose and ears. James Cooke, 66, and Dori Frame, 51, live with a condition called prosopagnosia, or face blindness. They both suffered separate events that affected their brains and caused them to suddenly lose the ability to recognize the faces of even their closest family members. However, there are others born with this condition. While it is unclear how many people suffer from face blindness, researchers are beginning to make progress in understanding how the prosopagnosia works by clarifying how the brain processes the both the face and the voice to help them recognize someone. One of the keys to understanding face recognition, it seems, is understanding how the brain comes to recognize voices. Some scientists had believed that faces and voices, the two main ways people recognize one another, were processed separately by the brain. Indeed, a condition parallel to prosopagnosia, called phonagnosia, similarly leaves a person unable to distinguish a familiar voice from an unfamiliar one. © 2011 The New York Times Company

Keyword: Attention
Link ID: 16188 - Posted: 12.27.2011

By KAREN BARROW Close your eyes. Picture your closest friend. Maybe you see her blue eyes, long nose, brown hair. Perhaps even her smile. If you saw her walking down the street it would match your imagined vision. But what if you saw nothing at all? James Cooke, 66, of Islip, N.Y., can’t recognize other people. When he meets someone on the street, he offers a generic “hello” because he can’t be sure if he’s ever met that person before. “I see eyes, nose, cheekbones, but no face,” he said. “I’ve even passed by my son and daughter without recognizing them.” He is not the only one. Those with prosopagnosia, also known as face blindness, can see perfectly well, but their brains are unable to piece together the information needed to understand that a collection of features represents an individual’s face. The condition is a neurological mystery, but new research has shed light on this strange malady. One of the keys to understanding face recognition, it seems, is understanding how the brain comes to recognize voices. Some scientists had believed that faces and voices, the two main ways people recognize one another, were processed separately by the brain. Indeed, a condition parallel to prosopagnosia, called phonagnosia, similarly leaves a person unable to distinguish a familiar voice from an unfamiliar one. © 2011 The New York Times Company

Keyword: Attention
Link ID: 16187 - Posted: 12.27.2011

Drug companies are working to develop a pure, more powerful version of a highly abused medicine, which has addiction experts worried that it could spur a new wave of abuse. The new pills contain the highly addictive painkiller hydrocodone, packing up to 10 times the amount of the drug as existing medications such as Vicodin. Four companies have begun patient testing, and one of them — Zogenix of San Diego — plans to apply early next year to begin marketing its product, Zohydro. If approved, it would mark the first time patients could legally buy pure hydrocodone. Existing products combine the drug with nonaddictive painkillers such as acetaminophen. Critics say they are especially worried about Zohydro, a timed-release drug meant for managing moderate to severe pain, because abusers could crush it to release an intense, immediate high. 'The next Oxycontin' "I have a big concern that this could be the next OxyContin," said April Rovero, president of the National Coalition Against Prescription Drug Abuse. "We just don't need this on the market." OxyContin, introduced in 1995 by Purdue Pharma of Stamford, Conn., was designed to manage pain with a formula that dribbled one dose of oxycodone over many hours. Abusers quickly discovered they could defeat the timed-release feature by crushing the pills. © CBC 2011

Keyword: Pain & Touch; Drug Abuse
Link ID: 16186 - Posted: 12.27.2011

By Laura Sanders Sea snails learn more effectively on an oddly timed series of training sessions rather than regularly spaced lessons, a new study finds. If the results extend to humans, they might suggest ways of improving students’ study habits. The work, published online December 25 in Nature Neuroscience, shows how a deep knowledge of biology and powerful computer models can lead to insights about the brain, says neuroscientist Eric Kandel of Columbia University, who won a Nobel prize in 2000 for his work on sea snail memory. When the rat-sized Aplysia californica receives an unpleasant shock, it retracts its gill and an appendage called a siphon. After numerous shocks, it will become sensitized, learning to retract the siphon and keep it in for a while. Scientists normally expose sea snails to the signal at regular intervals over several hours to sensitize the animals. But Jack Byrne of the University of Texas Medical School at Houston and colleagues wondered whether there was a better way. “There’s no real logic for why people use one protocol over another, other than it works,” he says. Kandel and others have worked out a lot of the biochemical details of how sea snails learn and form memories. When the creatures start to learn something, two major molecular cascades kick off in nerve cells. Genes jump into action, churning out proteins that then spur other genes into action. One of these cascades happens quickly, and the other one is sluggish, but both need to deliver their products at the same time for a memory to stick. Y. Zhang et al. Computational design of enhanced learning protocols. Nature Neuroscience. Published online December 25, 2011. doi: 10.1038/nn.2990. © Society for Science & the Public 2000 - 2011

Keyword: Learning & Memory; Evolution
Link ID: 16185 - Posted: 12.27.2011

By NATALIE ANGIER VIEWED superficially, the part of youth that the psychologist Jean Piaget called middle childhood looks tame and uneventful, a quiet patch of road on the otherwise hairpin highway to adulthood. Said to begin around 5 or 6, when toddlerhood has ended and even the most protractedly breast-fed children have been weaned, and to end when the teen years commence, middle childhood certainly lacks the physical flamboyance of the epochs fore and aft: no gotcha cuteness of babydom, no secondary sexual billboards of pubescence. Yet as new findings from neuroscience, evolutionary biology, paleontology and anthropology make clear, middle childhood is anything but a bland placeholder. To the contrary, it is a time of great cognitive creativity and ambition, when the brain has pretty much reached its adult size and can focus on threading together its private intranet service — on forging, organizing, amplifying and annotating the tens of billions of synaptic connections that allow brain cells and brain domains to communicate. Subsidizing the deft frenzy of brain maturation is a distinctive endocrinological event called adrenarche (a-DREN-ar-kee), when the adrenal glands that sit like tricornered hats atop the kidneys begin pumping out powerful hormones known to affect the brain, most notably the androgen dihydroepiandrosterone, or DHEA. Researchers have only begun to understand adrenarche in any detail, but they see it as a signature feature of middle childhood every bit as important as the more familiar gonadal reveille that follows a few years later. © 2011 The New York Times Company

Keyword: Development of the Brain; Hormones & Behavior
Link ID: 16184 - Posted: 12.27.2011

by Richard Knox Debra Meyerson was hiking near Lake Tahoe 15 months ago when a stroke destroyed part of the left side of her brain, leaving her literally speechless. It happens to more than 150,000 Americans a year. But now Meyerson is learning to talk again through an approach that trains the undamaged right side of her brain to "speak." Specifically, it's a region that controls singing. For more than 100 years, it's been known that people who can't speak after injury to the speech centers on the left side of the brain can sing. In the 1970s, Boston researchers started to use a sort of "singing therapy" to help stroke survivors speak again. However, it never caught on much – perhaps because a lot of therapists, not to mention patients, weren't comfortable singing what they wanted to say. And back then, the science wasn't advanced enough to show the actual changes in the brain that result from the therapy. That's changing fast. Congresswoman Gabrielle Giffords, who has had a version of "singing therapy," astounded everyone by her ability to speak again – albeit so far in single words and short phrases. Nearly a year ago, a would-be assassin's bullet tore through the speech center in Giffords' left brain. Copyright 2011 NPR

Keyword: Stroke; Language
Link ID: 16183 - Posted: 12.27.2011

By Kay Lazar, Globe Staff Boston researchers say they have found a new method for detecting subtle brain changes in people who have no memory problems but who may already be in the earliest stages of Alzheimer’s disease. The findings, published online today in the medical journal Neurology, may help speed clinical trials for potential Alzheimer’s treatments, according to Dr. Bradford Dickerson, an associate professor of neurology at Harvard Medical School and lead author of the study. “We need efficient, cost-effective ways to screen people for research,” said Dickerson, who also is a brain specialist at Massachusetts General Hospital. “This will potentially give us a tool that will help identify people in a more efficient manner.” Dickerson said his screening method is not ready for use in physicians’ offices. Researchers and the medical community still must pinpoint reliable markers for the disease, that could be used much the same way doctors now measure early signs of heart disease by monitoring patients’ cholesterol levels. Dickerson’s team used brain scans to measure the thickness in nine specific areas of the brain in 159 people who did not show signs of dementia or other cognitive problems. © 2011 NY Times Co.

Keyword: Alzheimers
Link ID: 16182 - Posted: 12.23.2011

By Ferris Jabr Once adult lab mice learn to associate a particular stimulus—a sound, a flash of light—with the pain of an electric shock, they don't easily forget it, even when researchers stop the shocks. But a new study in the December 23 issue of Science shows that the antidepressant Prozac (fluoxetine) gives mice the youthful brain plasticity they need to learn that a once-threatening stimulus is now benign. The research may help explain why a combination of therapy and antidepressants is more effective at treating depression, anxiety and post-traumatic stress disorder (PTSD) than either drugs or therapy alone. Antidepressants may prime the adult brain to rewire faulty circuits during therapy. Nina Karpova, Eero Castrén and their colleagues at the University of Helsinki's Neuroscience Center created and extinguished fearful behaviors in mice. First, Castrén placed mice in a cage and repeatedly played a tone just before electrically shocking their feet. Soon the animals froze in fear whenever they heard the tone, at which point Castrén put them through "extinction training." He moved the mice to a different cage and played the same tone again. This time there was no electric shock. Researchers have previously shown that young mice less than three weeks old quickly learn that the tone is no longer a herald of danger and stop freezing in fear. But adult mice are harder to put at ease. Even if the adults become less fearful during extinction training, their relaxation is not permanent—a week later the tone turns them into statues again. © 2011 Scientific American,

Keyword: Depression; Neurogenesis
Link ID: 16181 - Posted: 12.23.2011