A chemical found in chocolate, tea, grapes and blueberries can improve the memory of mice, research suggests. The Salk Institute study could lead to further tests to see if epicatechin also works on humans. The study, published in the Journal of Neuroscience, suggests it improves blood flow in the brain - especially in combination with extra exercise. However, nutritionists warn chocolate is high in fat and sugar, which may undo any potential benefits. This is not the first study to find a link between 'flavanol' chemicals in certain foods and health benefits - other studies claim that cardiovascular health can be improved by including them in the diet. The researchers, led by Dr Henriette van Praag, working with chocolate firm Mars, compared mice fed a typical diet with those fed a diet supplemented with epicatechin. Half the mice in each group were allowed to run on a wheel for two hours each day and then, a month later, were trained to find a platform hidden in a pool of water. Those that both exercised and ate the epicatechin diet remembered the location of the platform longer than the other mice. The epicatechin-fed mice who did not exercise also showed enhanced memory, but to a lesser degree. The mice on the special diet appeared to have greater blood vessel growth in certain parts of their brain, alongside more mature brain nerve cells. Dr van Praag said: "A logical next step will be to study the effects of epicatechin on memory and brain blood flow in aged animals - and then humans, combined with mild exercise." Dr Mark Mattson, from the US National Institute on Ageing, said: "This is an important advance because it identifies a single natural chemical with memory-enhancing effects, suggesting it may be possible to optimise brain function by combining exercise and dietary supplementation." (C)BBC

Keyword: Learning & Memory
Link ID: 10358 - Posted: 05.31.2007

By Elizabeth Pennisi Red is the color of romance, and not just for people. Among South American monkeys called red uakari, females prefer males with fiery faces: the brighter the red, the better. New research indicates such dramatic coloration arose only after primates evolved the ability to see it, and not vice versa, as some researchers have suggested. Primates stand out among placental mammals in that most can view the entire rainbow. About a century ago, researchers proposed that the ability to see red, orange, and yellow became the norm because it allowed primates to spot edible fruit and nutritious young, reddish leaves. But while studying howler monkeys in Costa Rica, graduate student André Fernandez of Ohio University in Athens noticed that these visually blessed creatures didn't always go for the ripe fruit. Puzzled, he began to wonder whether color vision had instead evolved for other reasons, perhaps--as some have suggested--to aid mate choice. Mate choice turned out to be an unlikely reason. To learn that, Fernandez and his adviser Molly Morris first reconstructed the evolutionary history of tricolor vision and skin color. He combed the scientific literature for information about more than 200 primates, noting skin and coat colors; whether each animal lived in groups; and whether each could see reds as well as the usual blues and greens. He then charted when these various traits appeared by looking at them in the context of each species' place on the primate family tree. © 2007 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Evolution
Link ID: 10357 - Posted: 06.24.2010

Roxanne Khamsi Imagine a painkiller that only switches on in injured tissue, leaving the rest of the body unaffected. That is the idea behind a new class of pH-dependent drugs that interfere with nerve signals to the brain and spinal cord - but only where the tissue is slightly acidic due to injury. Normal tissue has a pH of around 7.4, but this drops to around 7.0 in injured tissue, largely because the blood supply is disrupted, resulting in the accumulation of waste products such as carbon dioxide and a switch to anaerobic respiration, which produces lactic acid. The new drugs act by blocking NMDA receptors, which are found on cells throughout the brain and central nervous system and are implicated in a variety of nerve functions, including pain sensitisation. Earlier generations of drugs, such as ketamine, also targeted NMDA receptors, but these often have unwanted side effects such as impaired movement or hallucinations, because they act on undamaged nerve tissue as well. “The drugs act by blocking NMDA receptors, which are found on cells throughout the brain and central nervous system”Ray Dingledine of the Emory University School of Medicine in Atlanta, Georgia, and his colleagues have now developed a compound called NP-A, that binds to the base of NMDA receptors and stops glutamate and a related neurotransmitter called NMDA from binding. A slight drop in pH can cause a significant boost in NP-A's ability to block the receptor - for example, a drop in pH from 7.6 to 6.9 causes the compound's activity to increase 62 fold. © Copyright Reed Business Information Ltd

Keyword: Pain & Touch
Link ID: 10356 - Posted: 06.24.2010

Marlowe Hood, AFP — Why does one sparrow boldly grab crumbs from an outstretched hand while another hops about nervously at a safe distance, afraid to collect a free meal? Baffling differences in behavior within the same species are not just an accident of nature but an expression of animal personality and part of a complex evolutionary strategy, a team of researchers argue in a theoretical study published Thursday in the British journal Nature. Once thought to be the exclusive domain of human beings, personality is increasingly seen by scientists as a trait common in wild animals, ranging from squids and spiders to mice and monkeys. It also serves a purpose, they say. Dozens of observational studies in recent years have shown that otherwise indistinguishable individuals — same size, age, habitat, sex — can consistently behave in very different ways, even when facing the same dangers or opportunities. Whereas one stickleback fish or great tit bird will stand and fight when confronted with a predator or rival, another may be more inclined to cut and run. © 2007 Discovery Communications Inc.

Keyword: Emotions; Evolution
Link ID: 10355 - Posted: 06.24.2010

By Mary Carmichael, Newsweek - Late into the night of May 2, 1863, a few hours after Thomas (Stonewall) Jackson took two bullets in his left arm at the Battle of Chancellorsville, surgeon Hunter Holmes McGuire sawed off the bleeding limb, trying to save the general's life. With the knife came another medical tool, one fairly new to the battlefield—a rag soaked in chloroform. As he awaited amputation, Jackson, who would die a week later, was as stoic as his nickname suggested. But as he slipped into unconsciousness, it's said, he betrayed his vulnerability in the face of pain just once, mumbling that the anesthesia was "an infinite blessing." For most of the 144 years since then, the military has stuck with similarly crude techniques for treating its soldiers' pain. Morphine, also given to Jackson and many others in the Civil War, is still the Army's most commonly used painkilling drug. It works, but compared with more-modern options, it's one step above chloroform and two above biting the bullet. Now, though, with casualties mounting in Iraq and Afghanistan, the military is being forced to change its strategy. More than 90 percent of wounded soldiers have made it off the battlefield—the highest survival rate in American history—only to overwhelm chronic-pain clinics when they come home. "We're seeing the tip of a tidal wave of pain," says Lt. Col. Chester (Trip) Buckenmaier, an anesthesiologist at Walter Reed Army Medical Center, who has emerged as a sort of pain czar for the Army. After decades of "sucking it up," the military has finally started to respond in new and innovative ways to this escalating pain crisis. Even as the VA hospital system has come under fire for poor care, Army doctors haven't just joined up in medicine's larger war against pain—they're leading the charge.

Keyword: Pain & Touch
Link ID: 10354 - Posted: 06.24.2010

Heidi Ledford As an ice cream melts in your mouth this summer, take a moment to contemplate the protein that may be bringing you that sense of cool relief — and numbing your tongue. Researchers have pinned down that particular protein in mice, and think that a similar one in humans does the same job. Three papers, two published recently in Neuron and the third in this week's issue of Nature, have shown that mice rely on a single protein, called TRPM8, to sense both cold temperatures and menthol, the compound that gives mints their cool sensation. The sensor also controls the pain-relieving effect of cool temperatures, but does not seem to play an important role in the response to painfully cold temperatures below 10 °C. TRPM8 is in the same family as the protein that detects heat and capsaicin, the compound that makes peppers hot. These proteins lie in the cell membranes of select neurons, and form channels that open and close in response to external signals. Both cold temperatures and menthol trigger TRPM8 to open, allowing small, positively charged molecules, such as calcium ions, to pour into the cell. Mice and humans each contain the gene that codes for TRPM8. In the lab dish, both versions open their channel when temperatures dip below 27 °C. Now, three teams have independently created mutant mice that cannot produce the TRPM8 protein. ©2007 Nature Publishing Group

Keyword: Pain & Touch
Link ID: 10353 - Posted: 06.24.2010

While most people need peace and quiet to cram for a test, the brain itself may need noise to learn, a recent study suggests. In experiments with monkeys, the researchers found that neural activities in the brain gradually change, even when nothing new is being learned. Challenging the monkeys to adjust their task triggered systematic changes in their neural activities on top of this background “noise.” The researchers said their findings suggest a new theory of how the brain learns. Traditional views held that learning occurs by rewiring neural circuitry that is normally stable. In contrast, the new theory proposes that neural circuitry is continually being rewired, even during behavior that does not change. According to the theory, this neural rewiring normally remains invisible at the behavioral level because the brain's motor cortex is redundant; many wiring configurations can accomplish the same behavior. “What surprised us most was that the neural representation of movement seems to change even when behavior doesn't seem to change at all,” said Howard Hughes Medical Institute investigator Sebastian Seung, one of the scientists who led the study. “This was a surprising degree of instability in the brain's representation of the world.” © 2007 Howard Hughes Medical Institute

Keyword: Learning & Memory
Link ID: 10352 - Posted: 06.24.2010

Some of the health benefits claimed for a new weight loss drug may not be justified, say experts. Rimonabant, launched in the UK last summer, has been shown to aid weight loss by reducing appetite. But a Drug and Therapeutics Bulletin paper suggests claims that it also has an additional positive impact on the body's chemistry have not been proved. However, the manufacturers said the findings had proved consistent across all trials. The National Institute for Health and Clinical Excellence (Nice) is currently appraising the drug for use on the NHS. Manufacturers Sanofi-Aventis claim it has been shown to cut levels of potentially harmful cholesterol, fats and sugars in the blood to a greater extent than would be expected by weight loss alone. In theory, this should help to reduce the risk of developing type 2 diabetes and heart disease. But the DTB paper argued that research had failed to prove that any positive impact on body chemistry was solely down to taking the drug. It was possible, for instance, that it was down to advice given to patients taking the drug to lead a more healthy lifestyle, and take more exercise. The paper also highlighted the fact that in trials rimonabant had no effect on levels of "bad" cholesterol, and little or no effect on blood pressure. It said the drug had not been effectively compared with other, cheaper weight loss drugs, such as Xenical (orlistat) and Reductil (sibutramine), which are both approved for NHS use. (C)BBC

Keyword: Obesity
Link ID: 10351 - Posted: 05.30.2007

Exposure to pesticides could lead to an increased risk of contracting Parkinson's disease, a study has found. Researchers discovered that high levels of exposure increased the risk by 39%, while even low levels raised it by 9%. However, the Aberdeen University researchers stressed that the overall risk of developing the disease remained small. In the UK, one person in 500 develops the incurable degenerative brain disease, or a similar illness. Symptoms often include unsteadiness and tremor in the hands or arms, often alongside difficulties with speech or movement. Other studies have pointed strongly towards exposure to pesticides being involved in some cases, with agricultural workers showing higher rates of the illness. The Aberdeen study, reported in the journal Occupational and Environmental Medicine, involved 959 cases of parkinsonism, a term used to describe people with diagnoses of Parkinson's Disease, and other, similar conditions. They all answered questioned about their lifetime occupational and recreational exposure to a variety of chemicals, including solvents, pesticides, iron, copper and manganese. Some have suggested that the head injuries involved in boxing could be linked to Parkinson's, so the patients were also asked whether they had ever been knocked unconscious. The study included more general questions about family health history and tobacco use. (C)BBC

Keyword: Parkinsons; Neurotoxins
Link ID: 10350 - Posted: 05.30.2007

The race to create more human-like robots stepped up a gear this week as scientists in Spain set about building an artificial cerebellum. The end-game of the two-year project is to implant the man-made cerebellum in a robot to make movements and interaction with humans more natural. The cerebellum is the part of the brain that controls motor functions. Researchers hope that the work might also yield clues to treat cognitive diseases such as Parkinson's. The research, being undertaken at the Department of Architecture and Computing Technology at the University of Granada, is part of a wider European project dubbed Sensopac Sensopac brings together electronic engineers, physicists and neuroscientists from a range of universities including Edinburgh, Israel and Paris with groups such as the German Aerospace Centre. It has 6.5m euros of funding from the European Commission. Its target is to incorporate the cerebellum into a robot designed by the German Aerospace Centre in two year's time. The work at the University of Granada is concentrating on the design of microchips that incorporate a full neuronal system, emulating the way the cerebellum interacts with the human nervous system. Implanting the man-made cerebellum in a robot would allow it to manipulate and interact with other objects with far greater subtlety than industrial robots can currently manage, said researcher Professor Eduardo Ros Vidal, who is co-ordinating work at the University of Granada. (C)BBC

Keyword: Movement Disorders; Robotics
Link ID: 10349 - Posted: 05.30.2007

LONDON - For female cheetahs in the Serengeti, the call of the wild is just too hard to resist, as new research shows that nearly half of their litters are made up of cubs with different fathers. And while the serial infidelities of the females does ensure a broader genetic mix to help the survival of the endangered species, it comes at a cost, the Zoological Society of London said Wednesday. “Mating with more than one male poses a serious threat to females, increasing the risk of exposure to parasites and diseases,” said Dada Gottelli, the zoological society’s lead scientist for the research. “Females also have to travel over large distances to find new males, making them more vulnerable to predation, so infidelity is a heavy burden.” Cheetahs are a threatened species and are declining in number in the areas they inhabit. © 2007 MSNBC.com © 2007 Microsoft

Keyword: Sexual Behavior; Evolution
Link ID: 10348 - Posted: 06.24.2010

By JANE E. BRODY As Sandy Kamen Wisniewski remembers, her hands always shook. She hid them in long sleeves and pockets and wrote only in block letters in school because at least that was readable. The tremor became much worse as she entered her teenage years, and if she was upset or under stress, it grew so bad she cringed with embarrassment and decided that it must all be psychological. Ms. Wisniewski, now 40, was 14 when she learned that she had not an emotional disorder, but a neurological condition called essential tremor — “essential” not because she needed it, but because no underlying factor caused it. It was not a prelude to Parkinson’s disease, nor was it caused by a hormonal problem, a drug reaction or nervousness. (Many people thought that Katharine Hepburn had Parkinson’s disease, when in fact she shook because she had essential tremor, as does Terry Link, a state senator in Illinois, and Gov. Jim Gibbons of Nevada.) This disorder, which in most cases is inherited, is so misunderstood and so often misdiagnosed that Ms. Wisniewski, who lives in Libertyville, Ill., decided to write a book about it. Called “I Can’t Stop Shaking,” the book was self-published last year through Dog Ear Publishing in Indianapolis. Her intent is to help the estimated 10 million people who suffer with essential tremor, often for decades without knowing what is wrong. Copyright 2007 The New York Times Company

Keyword: Movement Disorders; Parkinsons
Link ID: 10347 - Posted: 06.24.2010

Whenever I hear "antidepressant medications" and "risk of suicide," I think of Liam. Just as I think of him whenever I hear the train whistle blow in the dark morning hours. Liam isn't his real name. I'm giving him a fake name to protect his family's privacy. According to eyewitnesses, Liam politely asked some people waiting for a commuter train whether the next train was scheduled to stop or pass on through. When they informed him it was passing through, he calmly walked onto the tracks, folded his arms, turned his back to the oncoming train and brutally ended his life. It made the news because it disrupted the rush-hour commute. If it weren't for the eyewitness accounts I wouldn't have believed it was suicide. People would describe Liam as the among the most stable, well-liked, fun, funny, happy-go-lucky people they knew-- someone I could imagine, even in his early 30's, maybe impulsively doing something risky like jumping a train for fun or a free ride, but never, ever deliberately walking in front of one. He had a beautiful wife, a baby on the way; a good job, a nice home; many talents and good physical health. But he'd become depressed. So depressed that he told family members and friends he needed help. So depressed that he sought help from a doctor. When Liam took his own life he had been on an antidepressant for only a few days. © ScienCentral, 2000-2007.

Keyword: Depression
Link ID: 10346 - Posted: 06.24.2010

By LAURA BLUE Anyone who reads a daily paper could be forgiven for wondering how carbs, alcohol, fats — a whole host of things, really — can be reported as healthy one day and unhealthy the next. Of the conflicted bunch, however, alcohol just might be most enduringly confusing: scientific studies proclaim that it protects against heart attack and stroke, while others suggest it promotes violent tendencies or destroys the liver. Why the mixed messages? A new study demonstrates what can go wrong. The latest in a long line of research on alcohol's benefits — sure to cause a stir — is a paper by geriatrics researchers at the University of Bari in Italy appearing in the May 22 issue of Neurology, revealing that the progression of dementia may be slower in people who drink moderately than in teetotalers. A survey of elderly Italians — 1,445 of whom had no cognitive impairment and 121 who suffered mild cognitive impairment (MCI) — found that, over 3.5 years, those with MCI who drank less than one drink a day progressed to dementia at a rate 85% slower than those who drank nothing. Drinking more did not seem to be better than drinking nothing. Expect big headlines to follow: "Booze boosts the brain"; "A drink a day keeps dementia away." The problem is, of course, that that's not what the Bari scientists actually wrote in their paper. They said only that a drink a day may keep dementia away. Like so many studies of this kind, where researchers follow a large group without making any interventions of their own, it can be hard to distinguish the effects of alcohol from the effects of other lifestyle factors. © 2007 Time Inc.

Keyword: Alzheimers; Drug Abuse
Link ID: 10345 - Posted: 06.24.2010

By ABIGAIL ZUGER, M.D. In bookstores, the science aisle generally lies well away from the self-help section, with hard reality on one set of shelves and wishful thinking on the other. But Norman Doidge’s fascinating synopsis of the current revolution in neuroscience straddles this gap: the age-old distinction between the brain and the mind is crumbling fast as the power of positive thinking finally gains scientific credibility. The credo of this revolution is neuroplasticity — the discovery that the human brain is as malleable as a lump of wet clay not only in infancy, as scientists have long known, but well into hoary old age. In classical neuroscience, the adult brain was considered an immutable machine, as wonderfully precise as a clock in a locked case. Every part had a specific purpose, none could be replaced or repaired, and the machine was destined to tick in unchanging rhythm until its gears corroded with age. Now sophisticated experimental techniques suggest the brain is more like a Disney-esque animated sea creature. Constantly oozing in various directions, it is apparently able to respond to injury with striking functional reorganization, and can at times actually think itself into a new anatomic configuration, in a kind of word-made-flesh outcome far more characteristic of Lourdes than the National Institutes of Health. Copyright 2007 The New York Times Company

Keyword: Development of the Brain; Learning & Memory
Link ID: 10344 - Posted: 06.24.2010

By MICHAEL D. LEMONICK Andrea Morales and Gavan Fitzsimons can both remember when and where their current research interest began. It came during a talk at the University of Pennsylvania a few years ago: Paul Rozin, a professor of psychology, took a cockroach that had been sterilized, dipped it into a glass of orange juice, then asked if anyone was willing to take a sip. Nobody was. But if an involuntary ewww just went through your mind, as it almost certainly did, the experiment is still working. Rozin specializes in the psychological study of disgust, and he was demonstrating the universal concept of touch transference. It's a fancy term for cooties. If something repulsive touches something benign, the latter, even if it's physically unchanged, becomes "infected." Fitzsimons and Morales, who teach marketing at Duke and Arizona State University, respectively, suspected this phenomenon had implications for the consumer marketplace--and in an article in this month's Journal of Marketing Research, they show that it does. In a series of studies, the researchers found not only that some products--trash bags, diapers, kitty litter, tampons--evoke a subconscious feeling of disgust even before they're used for their ultimate messy purposes, but they can also transfer their general ickiness to anything they come in contact with. "We were pretty surprised at how strong the effect was," says Fitzsimons. "This is probably the most robust result in my career." Copyright © 2007 Time Inc

Keyword: Emotions
Link ID: 10343 - Posted: 06.24.2010

By Sally Lehrman When Eric Vilain began his medical school rotation two decades ago, he was assigned to France's reference center for babies with ambiguous genitalia. He watched as doctors at the Paris hospital would check an infant's endowment and quickly decide: boy or girl. Their own discomfort and social beliefs seemed to drive the choice, the young Vilain observed with shock. "I kept asking, How do you know?' " he recalls. After all, a baby's genitals might not match the reproductive organs inside. By coincidence, Vilain was also reading the journals of Herculine Barbin, a 19th-century hermaphrodite. Her story of love and woe, edited by famed social constructionist Michel Foucault, sharpened his questions. He set on a path to find out what sexual "normality" really meant--and to find answers to the basic biology of sex differences. Today the 40-year-old French native is one of a handful of geneticists on whom parents and doctors rely to explain how and why sex determination in an infant may have taken an unusual route. In his genetics laboratory at the University of California, Los Angeles, Vilain's findings have pushed the field toward not only improved technical understanding but more thoughtful treatment as well. "What really matters is what people feel they are in terms of gender, not what their family or doctors think they should be," Vilain says. Genital ambiguity occurs in an estimated one in 4,500 births, and problems such as undescended testes happen in one in 100. Altogether, hospitals across the U.S. perform about five sex-assignment surgeries every day. © 1996-2007 Scientific American, Inc.

Keyword: Sexual Behavior
Link ID: 10342 - Posted: 06.24.2010

Nora Schultz All babies can grow up speaking any language, but now researchers have uncovered evidence that genes may in fact play a part in learning so-called "tonal languages", such as Chinese. Subtle pronunciation differences in tonal languages can radically change the meaning of words, which may be one reason why such languages are so hard to learn for speakers of non-tonal languages like English. So for a non-native Chinese speaker, to enquire after the health of someone’s mother might easily result in a query about the wellbeing of their horse. And now it appears that there may after all be something in our genes that affects how easily tonal languages can be learned. Such are the findings of Dan Dediu and Robert Ladd of Edinburgh University, UK, who have discovered the first clear correlation between language and genetic variation. Using statistical analysis, the pair showed that people in regions where non-tonal languages are spoken are more likely to carry different, more recently evolved forms of two brain development genes, ASPM and Microcephalin, than people in tonal regions. Dediu and Ladd accounted for geography and history, and the gene differences remained. © Copyright Reed Business Information Ltd.

Keyword: Language; Development of the Brain
Link ID: 10341 - Posted: 06.24.2010

Studies in mice have shown that lithium, a drug widely used to treat mood disorders in humans, can provide relief from the crushing symptoms of a fatal brain disease, according to researchers at the Howard Hughes Medical Institute (HHMI) at the Baylor College of Medicine. A team led by HHMI investigator Huda Y. Zoghbi did a series of experiments in mice that showed lithium, a psychiatric drug used to stabilize mood shifts, can ease the symptoms of spinocerebellar ataxia type 1, an inherited neurodegenerative disorder. Their research article was published on May 28, 2007, in the journal Public Library of Science (PLoS) Medicine. "The results are very exciting," said Zoghbi. "It's really hard to improve multiple symptoms (in a condition). Lithium seems to improve several in this case, not just one." The new findings are important because they suggest it may be possible to use the drug to alleviate deteriorations in motor coordination, learning and memory manifested by the spinocerebellar ataxia. At present, treatments for the condition are limited and patients, who are usually diagnosed in their thirties or forties, experience a gradual decline in motor and memory function and die within a few years of onset of the disease. © 2007 Howard Hughes Medical Institute.

Keyword: Movement Disorders
Link ID: 10340 - Posted: 06.24.2010

By GINA KOLATA Dr. Diana Fite, a 53-year-old emergency medicine specialist in Houston, knew her blood pressure readings had been dangerously high for five years. But she convinced herself that those measurements, about 200 over 120, did not reflect her actual blood pressure. Anyway, she was too young to take medication. She would worry about her blood pressure when she got older. Then, at 9:30 the morning of June 7, Dr. Fite was driving, steering with her right hand, holding her cellphone in her left, when, for a split second, the right side of her body felt weak. “I said: ‘This is silly, it’s my imagination. I’ve been working too hard.’ ” Suddenly, her car began to swerve. “I realized I had no strength whatsoever in my right hand that was holding the wheel,” Dr. Fite said. “And my right foot was dead. I could not get it off the gas pedal.” She dropped the cellphone, grabbed the steering wheel with her left hand, and steered the car into a parking lot. Then she used her left foot to pry her right foot off the accelerator. She pulled down the visor to look in the mirror. The right side of her face was paralyzed. With great difficulty, Dr. Fite twisted her body and grasped her cellphone. Copyright 2007 The New York Times Company

Keyword: Stroke
Link ID: 10339 - Posted: 06.24.2010