Lauran Neergaard, Associated Press — When aging hampers memory, some people's brains compensate to stay sharp. Now scientists want to know how those brains make do — in hopes of developing treatments to help everyone else keep up. This is not Alzheimer's disease, but the wear-and-tear of so-called normal aging. New research is making clear that memory and other brain functions decline to varying degrees even in otherwise healthy people as they age, as anyone who habitually loses car keys probably suspected. The question is how to gird our brains against time's ravages, a question becoming critical as the population grays. If you're 65 today, odds are you'll live to 83. But improving health care means people in their 50s today may live another 40 years. "I don't think we've recognized, as scientists or a society, (that) this is the front-and-center public health issue we face as a nation," Dr. Denise Park, director of the University of Illinois' Center for Healthy Minds, told fellow brain specialists assembled by the government last week. "We need to understand how to defer normal cognitive aging ... the way we've invested in fighting heart disease and cancer." There are intriguing clues, gleaned from discoveries that some seniors' brains literally work around aging's damage, forging new pathways when old ones disintegrate. © 2007 Discovery Communications

Keyword: Alzheimers
Link ID: 10850 - Posted: 06.24.2010

By Roger Highfield, Science Editor A "beauty spot", wonky nose or a lopsided grin are a turnoff, according to a study published today that shows that symmetry is sexy. Research to find whether symmetrical faces are more or less attractive in the UK and the Hadza of Tanzania, one of the last hunter gatherer cultures, has found that a symmetrical face is indeed a turn on, whatever your culture. advertisementThe find, resulting from presenting a series of faces for inspection by 80 Britons and 40 Hadza challenges feminist ideas, epitomised by the American writer Naomi Wolf, who argued that there is no such thing as a quality called beauty that "objectively and universally exists". Even the father of evolution, Charles Darwin was struck by cultural differences in attractiveness. He wrote: "It is certainly not true that there is in the mind of man any universal standards of beauty with respect to the human body." Today, in the Proceedings of the Royal Society, Biological Sciences, research by Dr Anthony Little of the University of Stirling, working with colleagues Coren Apicella at Harvard University and Frank Marlowe Florida State University, shows that symmetry transcends racial and national boundaries: a lopsided face is less attractive to both Hadza and Britons, so that the age-old idea that beauty is in the eye of the beholder is a romantic myth. © Copyright of Telegraph Media Group Limited 2007

Keyword: Sexual Behavior; Evolution
Link ID: 10849 - Posted: 06.24.2010

A look of horror will grab the attention of those around you faster than a smile, US research shows. Individuals react more quickly to a fearful expression than to faces showing other emotions such as joy, a study in the journal Emotion found. Researchers from Vanderbilt University found the same speedy reaction to fear when only the eyes were visible. The brain responds very quickly to all facial expressions - at a speed of less than 40 milliseconds. So to assess if certain emotions prompt a faster reaction, the researchers had to slow down the speed at which volunteers became aware of facial expressions. Volunteers looked through a viewer which flashed a black and white, quick-changing pattern to one eye and a static image of a face to the other eye. The flashing image had the effect of slowing down the speed at which the individual noticed the face. Participants became aware of a fearful expression far faster than a neutral or happy face. Reaction to happy faces was consistently slower than for the other expressions looked at. The fast reaction to fear was the same if the whole face was visible or just the eyes. (C)BBC

Keyword: Emotions
Link ID: 10848 - Posted: 10.15.2007

UK-based scientists say they have identified the brain circuits that control how much we eat. The Nature study, by University College London and King's College London, could aid development of new obesity drugs. Using brain scans, the teams showed the appetite-regulating hormone peptide YY (PYY) produces a more complex pattern of activity in the brain than thought. It targets not only the primitive areas controlling basic hunger urges, but also the pleasure and reward centres. PYY is released from the gut into the bloodstream after eating and signals to the brain that food has been eaten. A nasal spray containing the hormone is currently being trialled to see if it can be used to tackle obesity. Studies on animals suggest it regulates appetite by acting in primitive parts of the brain such as the hypothalamus and brainstem. The latest study showed that the same was true in humans. But the hormone was also found to act in the cortico-limbic regions that determine the pleasure sensations associated with eating food. The biggest effect of all was found in an area called the orbitofrontal cortex (OFC) - a region thought to make overall sense of the pleasure sensation. The researchers found that the greater the change in activity in that area, the less the volunteers ate. Eight normal-weight men took part in the study. After 14 hours without food, they were given a drip of either PYY or a placebo for 100 minutes while their brains were scanned using an MRI machine. Thirty minutes later they were offered an unlimited meal. Each volunteer was tested twice, a week apart, once with PYY and once with the placebo. (C)BBC

Keyword: Obesity
Link ID: 10847 - Posted: 10.15.2007

By LISA SANDERS, M.D. The indifferent voice crackled through the hospital intercom. “Please, I am so, so thirsty,” answered the young woman in the bed. “I feel awful, but I know I’d feel better if I could just have a drink of water.” Her mouth was so dry it hurt, and her head pounded painfully. She felt dizzy and sweaty. “I’ll let your nurse know,” replied the voice. It seemed to the woman that her life had always revolved around water. She was always thirsty, always drinking. When she went out, she carried two or three water bottles with her. When she went to sleep, she needed two glasses of water at her bedside. That morning she had come to the hospital for a C-section to deliver a baby too big to get out any other way. Now the beautiful baby was sleeping, and the mother was desperately thirsty. When the nurse appeared with a pitcher of water, the woman almost wept with relief. The next morning, Dr. Heidi Chen, the OB-GYN intern, woke the patient early. The young doctor was worried, and it showed on her face. The patient had drunk an enormous amount of water in the hours following her C-section — well over three gallons. Her urine output had been just as remarkable. The doctor needed to figure out what was going on. Copyright 2007 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 10846 - Posted: 06.24.2010

CHICAGO -- What's so unusual about a baby fascinated with spinning a cup, or a toddler flapping his hands, or a preschooler walking on her toes? Parents and even doctors sometimes miss these red flags for autism, but a new online video "glossary" makes them startlingly clear. Dozens of video clips contrast the behavior of autistic kids with that of unaffected children. Some of the side-by-side differences can make you gasp. Others are more subtle. The free Web site, debuting today, also defines and depicts "stimming," echolalia and other confusing-sounding terms that describe autistic behavior. Stimming refers to repetitive, self-stimulating or soothing behavior, including hand-flapping and rocking, that autistic children sometimes do in reaction to light, sounds or excitement. Echolalia is echoing or repeating someone else's words or phrases, sometimes out of context. © 2007 The Washington Post Company

Keyword: Autism
Link ID: 10845 - Posted: 06.24.2010

— Japanese researchers say they have found a way to let people stroll through the virtual world of Second Life using their own imagination, in a development that could help paralysis patients. Previous studies have shown people can move computer cursors through brain waves, but the Japanese team says it is the first to apply the technology to an Internet virtual world. The technology "would enable people suffering paralysis to communicate with others or do business through chatting and shopping in a virtual world," said Junichi Ushiba, associate professor at Keio University's rehabilitation centre. Second Life is an increasingly popular virtual world in which people — and animals — are represented by animated avatars and can do everything from social activities to shopping. Ushiba said Second Life could motivate patients with severe paralysis, who are often too depressed to undergo rehabilitation. "If they can see with their own eyes their characters moving around, it could reinvigorate their brain activity and restore some functions," he said. Under the technology, a person wearing head gear embedded with electrodes, which analyse brain waves in the cerebral motor cortex, would be able to move a Second Life character forward by thinking he or she is walking. © 2007 Discovery Communications

Keyword: Robotics
Link ID: 10844 - Posted: 06.24.2010

Erika Check Hayden A survey of Alzheimer’s patients has identified some distinctive proteins in the blood that could be used to diagnose the disease more effectively. Earlier and more definitive diagnoses are wanted to help target treatments — both existing and experimental. More than 5 million North Americans currently have Alzheimer’s disease. It is estimated that about quarter of a million developing cases go undiagnosed every year. Doctors can diagnose Alzheimer’s only by eliminating other possible causes of mental decline. There is no definitive test for the disease until a person dies, when surgeons can examine his or her brain tissue to look for the protein plaques and tangles that are the hallmark of the disease. Researchers are trying to change that situation by finding biomarkers — definitive biological signatures of the disease. Today, a team led by neuroscientist Tony Wyss-Coray of Stanford University School of Medicine in California reports in Nature Medicine 1 the discovery of 18 proteins that together seem fairly diagnostic for the condition. If the biomarkers are confirmed by more rigorous testing, they could result in a simple blood test by which doctors could diagnose the disease. Sufferers could then take medications to delay the effects of Alzheimer’s, plan to change their finances or living situation, or enroll in clinical trials to test potential new drugs. © 2007 Nature Publishing Group

Keyword: Alzheimers
Link ID: 10843 - Posted: 06.24.2010

The Dutch government is banning the sale of all magic mushrooms after a series of high-profile incidents involving tourists who had taken them. The decision will take effect within several months, said a spokesman for the Dutch justice ministry. A major Dutch producer of the psychedelic mushrooms said he stood to lose millions of euros as a result. The Netherlands is famed for its liberal drugs policy, with marijuana openly sold in licensed cafes. Magic mushrooms, more properly known as psilocybe, contain the psychedelic chemicals psilocybin and psilocin. "We intend to forbid the sale of magic mushrooms," said justice ministry spokesman Wim van der Weegen. That means shops caught doing so will be closed." Currently in the Netherlands the sale of dried magic mushrooms - in which the psychoactive chemicals psilocybin and psilocin are stronger - is banned but fresh mushrooms are allowed. This is because it is more difficult to ascertain how much of the chemicals fresh mushrooms contain. But Mr Van der Weegen said this was exactly the issue. "The problem with mushrooms is that their effect is unpredictable. It's impossible to estimate what amount will have what effect." Calls for a re-evaluation of the drug grew after a 17-year-old French girl jumped from a building after eating magic mushrooms during a school trip to Amsterdam in March. Other incidents involving the drug have included an Icelandic tourist jumping from a balcony and breaking both legs and a Danish tourist driving his car wildly through a camping ground, narrowly missing sleeping campers. (C)BBC

Keyword: Drug Abuse
Link ID: 10842 - Posted: 10.13.2007

Seth Borenstein, Associated Press — If that craving for chocolate sometimes feels like it is coming from deep in your gut, that's because maybe it is. A small study links the type of bacteria living in people's digestive system to a desire for chocolate. Everyone has a vast community of microbes in their guts. But people who crave daily chocolate show signs of having different colonies of bacteria than people who are immune to chocolate's allure. That may be the case for other foods, too. The idea could eventually lead to treating some types of obesity by changing the composition of the trillions of bacteria occupying the intestines and stomach, said Sunil Kochhar, co-author of the study. It appears Friday in the peer-reviewed Journal of Proteome Research. Kochhar is in charge of metabolism research at the Nestle Research Center in Lausanne, Switzerland. The food conglomerate Nestle SA paid for the study. But this isn't part of an effort to convert a few to the dark side (or even milk) side of cocoa, Kocchar said. In fact, the study was delayed because it took a year for the researchers to find 11 men who don't eat chocolate. Kochhar compared the blood and urine of those 11 men, who he jokingly called "weird" for their indifference to chocolate, to 11 similar men who ate chocolate daily. They were all healthy, not obese, and were fed the same food for five days. © 2007 Discovery Communications

Keyword: Obesity
Link ID: 10841 - Posted: 06.24.2010

Bruce Bower Here's an evolutionary talking point: Two new studies quantify parts of the mechanism by which frequently used words change slowly over many millennia whereas rarely used words more rapidly take on new forms. In fact, frequency of word usage exerts a "lawlike" influence on the rapidity of language evolution, the research teams conclude in the Oct. 11 Nature. This discovery offers a new tool for retracing the history of major language families, reconstructing ancient tongues, and predicting which words will undergo future alterations. "We expect all languages to diverge initially in the least frequently used parts of their vocabulary," says evolutionary biologist Mark Pagel of the University of Reading in England. Pagel's group focused on Indo-European languages. Some words for the same meanings differ strikingly across the more than 100 languages and dialects of that family, while others take similar forms. The researchers first determined 200 basic vocabulary meanings in 87 Indo-European languages spoken during the past 6,000 to 10,000 years. They then applied a statistical technique to modern-language data in order to estimate the spoken frequencies of the corresponding words in English, Spanish, Russian, and Greek. ©2007 Science Service

Keyword: Language; Evolution
Link ID: 10840 - Posted: 06.24.2010

The mystery of how an animal has survived for 80 million years without sex has been solved by UK scientists. A Cambridge team says the single-celled creature owes its existence to a genetic quirk that offers some recompense for prolonged celibacy. Many asexual organisms have died out because they cannot adapt to changes in the natural world. But an evolutionary trick allows this pond-dweller to survive when conditions change, researchers report in Science. The animal is a single-celled invertebrate known as a bdelloid rotifer. It lives in freshwater pools. If deprived of water, it survives in a desiccated state until water becomes available again. The secret to this novel survival mechanism lies in a twist of asexual reproduction, whereby the animal is able to make two separate proteins from two different copies of a key gene. Dr Alan Tunnacliffe, from the Institute of Biotechnology at the University of Cambridge, who led the research, said his team had been able to show for the first time that gene copies in asexual animals can have different functions. "It's particularly exciting that we've found different, but complementary, functions in genes which help bdelloid rotifers survive desiccation," he explained. "Evolution of gene function in this way can't happen in sexual organisms, which means there could be some benefit to millions of years without sex after all." The researchers discovered that two copies of a particular gene, known as LEA, in the asexual pond-dweller are different - giving rise to proteins with separate functions that protect the animal during dehydration. One copy stops other essential protein molecules from clumping together as the animal dries out, while the second copy helps to maintain the fragile membranes that surround the creature's cells. (C)BBC

Keyword: Sexual Behavior; Evolution
Link ID: 10839 - Posted: 10.13.2007

By Sacha Pfeiffer ANYONE WHO HAS browsed a supermarket in the last few years can't help but notice the shelves are practically bursting into flames. Spicy Guacamole Pringles. Tyson Hot 'n' Spicy Buffalo Style Chicken Chunks. Mo Hotta Mo Betta Cayenne Garlic Hot Sauce. Restaurants are no different. McDonald's has its Chipotle BBQ Snack Wrap; Friday's has its Wicked Wings. The spice-driven cooking of India, Thailand, and Sichuan China is responsible for a growing percentage of American takeout dollars every year. It's clear that Americans have developed an addiction to food with sinus-clearing pizzazz. Why is hot so hot? The conventional explanation is that the nation has an increasingly adventurous palate. Immigration and prosperity have made Americans more sophisticated eaters, pushing wasabi peas into the mainstream, along with chili-Thai lime cashews, cayenne chocolate bars, and other high-octane combinations. But some food scientists and market researchers think there is a more surprising reason for the broad nationwide shift toward bolder flavors: The baby boomers, that huge, youth-chasing, all-important demographic, are getting old. As they age, they are losing their ability to taste - and turning to spicier, higher-flavor foods to overcome their dulled senses. Chiefly because of degenerating olfactory nerves, most aging people experience a diminished sense of taste, whether they realize it or not. But unlike previous generations, the nation's 80 million boomers have broad appetites, a full set of teeth, and the spending power to shape the entire food market. © 2007 The New York Times Company

Keyword: Chemical Senses (Smell & Taste); Development of the Brain
Link ID: 10838 - Posted: 06.24.2010

by Nerissa Hannink Question: Why has the debate over nature vs nurture existed for so long? Answer: People are interested in the debate as they are curious about themselves, about their children, and unlike nuclear physics, it's something they can grapple with as an amateur. The debate has also persisted as it's so difficult to resolve. We know that we come with innate characteristics and that our environment influences us, but actual explanations are hard to come by. I find it hard to believe that anyone who's had two children does not believe in the influence of genes. The second child comes into the same environment as the first, but has an entirely different approach to the world. And yet there are obvious similarities too, because they have shared genes. We actually ought to be more similar, but because our genes are scrambled in sexual reproduction we get a unique deal of the cards. Question: Do you think the term 'Nature via nurture' has resolved much of the debate? Answer: I'm hoping that the term will be a helpful slogan under which to recognise that there is a new way of understanding the issue through figuring out how genes work. Because, nature is not the opposite of nurture, and genes are at the mercy of our experiences. ©2007 Luna Media Pty Ltd

Keyword: Development of the Brain
Link ID: 10837 - Posted: 06.24.2010

Anna Gosline A drug used to treat seizures and migraines may help alcoholics quit the bottle, according to a study in the US. And unlike other medications for alcohol addiction, sufferers can get help without having to completely dry out first. "You can be treated immediately for the disorder when you are in maximum crisis," says the lead author Bankole Johnson at the University of Virginia, Charlottesville, US. Johnson and colleagues followed the progress of 317 individuals with alcohol dependence for 14 weeks. Half received treatment with the drug topiramate, an anti-convulsant sold under the brand name Topamax, while the other half received a placebo. At the start of the study, participants were averaging about 11 drinks per day, and drinking heavily on more than 80% of their days. They totally abstained on approximately three days a month. By the end of the study, those receiving the drug reported drinking heavily on just 20% of days. They also averaged only 3.5 drinks per day, and managed to stay completely sober more than half the time. The control group also improved, but significantly less. They drank heavily on more than 40% of days, consumed six drinks per day, and abstained from drinking about a third of the time. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse; Epilepsy
Link ID: 10836 - Posted: 06.24.2010

By Lisa M. Krieger Physicists from the University of California-Santa Cruz have built a tool that studies how the eye processes the busy world around it, transforming the chaos of incoming light into elegantly moving images. The tiny device, which detects patterns of signals sent from the eye to the brain, could someday be used to help design retinal prosthetic devices - or even artificial vision. "We're able to see patterns of electrical activity in a large population of neurons," said Alan Litke of the Santa Cruz Institute for Particle Physics at UCSC. "There could be applications of this technology to many different areas of neuroscience." As described in today's issue of the weekly Journal of Neuroscience, the tool helps explain why seeing is believing. Eyes are exquisite interpreters of light, able to extract life-saving information from a mere pattern of rays - such as whether an oncoming truck is about to flatten you, or has slowed down to allow you to cross safely. Upon absorbing a single particle of light, or photon, retina cells fire off an electrical signal to the brain via the optic nerve. As few as six of these photon signals are required for the brain to perceive a flash. But how does the retina convert light into messages to the brain? Copyright 2007 San Jose Mercury News

Keyword: Vision; Robotics
Link ID: 10835 - Posted: 10.11.2007

Research into the brain's response to speech when under sedation has revealed reduced activity in areas critical for memory and understanding language. Cambridge University scientists used brain imaging to find evidence which may influence the amount of anaesthetic given to patients undergoing surgery. It may also affect attitudes to patients in a coma or vegetative state. Researchers said: "The brain processes speech when sedated but it appears not to fully comprehend or remember it." Using a scanning technique called functional magnetic resonance imaging (fMRI) that registers brain activity, Dr Matt Davis, a cognitive neuroscientist at Cambridge University, and his colleagues mapped speech-related brain activity in volunteers at varying levels of sedation. Their aim was to show how the brain's response to speech changed as people became more sedated and whether understanding of speech might continue even while consciousness and memory were impaired. Professor David Menon, professor of anaesthesia at the University of Cambridge, said the research has important parallels in two clinical situations. "A small proportion of anaesthetised patients report memories of events that occurred in the operating theatre, implying an inadvertent return of consciousness. It is possible that even more patients may have some awareness of events during anaesthesia, but this may fail to be detected because patients have no memories of the event afterwards. (C)BBC

Keyword: Miscellaneous
Link ID: 10834 - Posted: 10.10.2007

US scientists have repaired the nerve damage caused by multiple sclerosis in lab experiments on mice. The team, from the Mayo Clinic in Rochester, hope their work will eventually lead to new treatments. MS is caused by a defect in the body's immune system, which turns in on itself, and attacks the fatty myelin sheath which coats the nerves. The researchers used a human antibody to re-grow myelin in mice with the progressive form of MS. They told a meeting of the American Neurological Association they hope to begin patient trials after perfecting the technique further in animal tests. MS affects around 85,000 people in the UK. Damage to the myelin coating undermines the ability of the nerves to work properly, leading to symptoms including blurred vision, loss of balance and, in some cases paralysis. Although the symptoms can be managed to some degree, there is currently no way to restore damaged myelin. Researcher Dr Moses Rodriguez said: "The concept of using natural human antibodies to treat disease of this kind has not yet been tested in humans, but these research findings are very promising". His colleague Dr Arthur Warrington said: "The findings could eventually lead to new treatments that could limit permanent disability". Myelin repair normally occurs in the body spontaneously, but MS appears to sabotage this mechanism. (C)BBC

Keyword: Multiple Sclerosis
Link ID: 10833 - Posted: 10.10.2007

By JOHN TIERNEY In 1988, the surgeon general, C. Everett Koop, proclaimed ice cream to a be public-health menace right up there with cigarettes. Alluding to his office’s famous 1964 report on the perils of smoking, Dr. Koop announced that the American diet was a problem of “comparable” magnitude, chiefly because of the high-fat foods that were causing coronary heart disease and other deadly ailments. He introduced his report with these words: “The depth of the science base underlying its findings is even more impressive than that for tobacco and health in 1964.” That was a ludicrous statement, as Gary Taubes demonstrates in his new book meticulously debunking diet myths, “Good Calories, Bad Calories” (Knopf, 2007). The notion that fatty foods shorten your life began as a hypothesis based on dubious assumptions and data; when scientists tried to confirm it they failed repeatedly. The evidence against Häagen-Dazs was nothing like the evidence against Marlboros. It may seem bizarre that a surgeon general could go so wrong. After all, wasn’t it his job to express the scientific consensus? But that was the problem. Dr. Koop was expressing the consensus. He, like the architects of the federal “food pyramid” telling Americans what to eat, went wrong by listening to everyone else. He was caught in what social scientists call a cascade. Copyright 2007 The New York Times Company

Keyword: Obesity
Link ID: 10832 - Posted: 06.24.2010

Jennifer Viegas, Discovery News — Ever wonder what your dog does when you aren't around? The answer might surprise you, suggests a new study that found our canine companions behave more logically in our absence. People exert a strong influence on canine choices, it seems, and not always for the better. Dogs are so attuned to our actions, in fact, that they will sometimes abandon logic entirely to please us. But abandoning reason for obedience may serve our pets well in the end. "I do not think that domestication made dogs less intelligent," lead author Anes Erdohegyi told Discovery News. "On the contrary, dogs seem to show special sophistication in understanding social situations." "However," she added, "it is true that focusing on the human...sometimes leads to erroneous behavior." Erdohegyi is a researcher in the Department of Ethology at Budapest's Eotvos Lorand University. She and her colleagues recruited 42 adult pet dogs and their owners for the study, which has been accepted for publication in the journal Animal Behavior. The only criterion for selection was that the dogs had to be "highly motivated to play with a toy." © 2007 Discovery Communications

Keyword: Evolution
Link ID: 10831 - Posted: 06.24.2010