By Bruce Bower Chimpanzees living in central Africa’s dense forests have no access to a hardware store, but that doesn’t stop them from assembling their own brand of toolkits. These apes use as many as five homemade tools in set sequences to obtain honey from beehives located at least 20 meters high in the trees, in fallen tree trunks and up to 1 meter underground, according to two new studies. Chimps living in Gabon’s Loango National Park modify tree branches of various lengths and widths to make complex tool sets for removing honey from the hives of different bee species, anthropologist Christophe Boesch of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and his colleagues report online May 19 in the Journal of Human Evolution. In other parts of Africa, chimps use only one or two tools at a time to obtain honey from hives, crack nuts or hunt small animals. Near Loango, in a forested region of the Congo Basin called the Goualougo Triangle, another group of chimps also makes and uses different types of tools to open beehives and gather honey, say Crickette Sanz, also of the Max Planck Institute for Evolutionary Anthropology, and David Morgan of Lincoln Park Zoo in Chicago. Chimps across Africa have developed regional tool-using traditions in honey gathering, Sanz and Morgan propose in the June International Journal of Primatology. In central African forests, hard-to-reach hives and competition for food with nearby gorillas have elicited complex forms of tool use by chimps, the researchers contend. That proposal challenges the traditional idea that advanced behaviors among human ancestors emerged only after they left the forest for wide-open savannas. Forest-dwelling ancestors could have achieved chimplike advances in tool-making as well, in Sanz and Morgan’s view. © Society for Science & the Public 2000 - 2009

Keyword: Evolution
Link ID: 12896 - Posted: 06.24.2010

by Michael Le Page, Copenhagen For women, it seems, sex is a big turn-off, reveals a brain scanning study. It shows that many areas of the brain switch off during the female orgasm - including those involved with emotion. "At the moment of orgasm, women do not have any emotional feelings," says Gert Holstege of the University of Groningen in the Netherlands. His team recruited 13 healthy heterosexual women and their partners. The women were asked to lie with their heads in a PET scanner while the team compared their brain activity in four states: simply resting, faking an orgasm, having their clitoris stimulated by their partner's fingers, and clitoral stimulation to the point of orgasm. The results of the study are striking. As the women were stimulated, activity rose in one sensory part of the brain, called the primary somatosensory cortex, but fell in the amygdala and hippocampus, areas involved in alertness and anxiety. During orgasm, activity fell in many more areas of the brain, including the prefrontal cortex, compared with the resting state, Holstege told a meeting of the European Society for Human Reproduction and Development in Copenhagen on Monday. In one sense the findings appear to confirm what is already known, that women cannot enjoy sex unless they are relaxed and free from worries and distractions. "Fear and anxiety levels have to go down for orgasm. Everyone knows this but we can see it happening in the brain," he explains. © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior
Link ID: 12895 - Posted: 06.24.2010

Sharon Begley There must be something deep in the human soul that makes us blame fate, birth, our parents and all sorts of other things beyond our control for how we turn out, and scientists are no less guilty of this. Case in point: a study published in the European Journal of Neuroscience this week concludes that something about the way the brain develops from birth (or earlier) leads some of us to be people persons—socially gregarious, enjoying the company of others—and some of us to be more aloof. True, the scientists hedge their bets by making the requisite acknowledgement that people's experience and behavior might act to alter their brain structure, something for which there is ample (and growing) evidence. (My favorites: London taxicab drivers develop a larger hippocampus (that's the site of spatial memory, a good thing to have to navigate London streets) and violin players develop larger somatosensory cortexes in regions devoted to the digits of their fingering hand. But the title of this latest bit of research tells it all: "The brain structural disposition to social interaction." Translation: brain structure comes first, and the result is that you are either a warm, friendly people person who delights in the company of others or a detached, independent, antisocial loner. The study itself was straightforward. Scientists led by Maël Lebreton and Graham Murray of the University of Cambridge had 4,349 men born in Finland in 1966 fill out a questionnaire that assesses sociability. (The men rated themselves on such points as whether such statements as "I make a warm personal connection with most people" and "I like to please other people as much as I can" describe them.) A high score means a high disposition to social relationships, emotional warmth and sociability called social reward dependence—a people person. A low score indicates a tendency to be socially insensitive and aloof. © 2009 Newsweek, Inc.

Keyword: Autism; Emotions
Link ID: 12894 - Posted: 06.24.2010

Joseph LeDoux We're living in the golden age of the brain. Researchers around the world are trying to figure out how Woody Allen's "second favorite organ" works. The US Society for Neuroscience has more than 40,000 members, and the International Brain Research Organization (IBRO) puts up impressive numbers from the rest of the planet. These legions of scientists, and their pioneering predecessors, have produced a tremendous amount of information about the brain, and also information about what goes wrong in the brains of people with neurological and psychiatric disorders. That's not to say we've got it all figured out, but we're making progress. As someone who studies the brain and also tries to disseminate information about the brain in a user-friendly, but scientifically accurate, way, I cringe when I read some pop accounts of brain research. For example, I recently saw this CNN headline: "Will right-brainers rule this century?" Clicking on the link took me to OPRAH.com, which promised, less hesitantly, to explain "Why right-brainers will rule this century." At least CNN considered the possibility that there was some question about the veracity of the statement. Oprah's headline implied it's a done deal. The current right brain craze was triggered by Daniel Pink's best selling book, A Whole New Mind. In the interview with Oprah, Pink, a former speech writer for Al Gore, says "in many professions, what used to matter most were abilities associated with the left side of the brain: linear, sequential, spreadsheet kind of faculties. Those still matter, but they're not enough. What's important now are the characteristics of the brain's right hemisphere: artistry, empathy, inventiveness, big-picture thinking. These skills have become first among equals in a whole range of business fields." Oprah bought 4500 copies. © 2009 HuffingtonPost.com, Inc.

Keyword: Emotions; Laterality
Link ID: 12893 - Posted: 06.24.2010

By Erica Westly Neuroscience textbooks typically portray the five senses as separate entities, but in the real world the senses frequently interact, as anyone who has tried to enjoy dinner with a stuffy nose can attest. Hearing and vision seem similarly connected, the most famous example being the “McGurk effect,” where visual cues, such as moving lips, affect how people hear speech. And now new research shows that touch can influence speech perception, too. David Ostry, a neuroscientist with co-appointments at McGill University and the New Haven, Conn.–based speech center Haskins Laboratories, has been studying for years the relation between speech and the somatosensory system, the network of receptors in skin and muscle that report information on tactile stimuli to the brain. In his most recent study, published in the Proceedings of the National Academy of Sciences USA, he and two Haskins colleagues found that subjects heard words differently when their mouths were stretched into different positions. The results have implications for neuroscientists studying speech and hearing as well as for therapists looking for new ways to treat speech disorders. In the study, a specially designed robotic device stretched the mouths of volunteers slightly up, down or backward while they listened to a computer-generated continuum of speech verbalizations that sounded like “head” or “had,” or something in between. When the subjects’ mouths were stretched upward, closer to the position needed to say “head,” they were more likely to hear the sounds as “head,” especially with the more ambiguous output. If the subjects’ mouths were stretched downward, as if to say “had,” they were more likely to hear “had,” even when the sounds being generated were closer to “head.” Stretching subjects’ mouths backward had no effect, implying a position-specific response. Moreover, the timing of the stretch had to match that of the sounds exactly to get an effect: the stretch altered speech perception only when it mimicked realistic vocalizations. © 1996-2009 Scientific American Inc

Keyword: Hearing; Language
Link ID: 12892 - Posted: 06.24.2010

A research institute devoted to Alzheimer's and related diseases has teamed up with a major maker of diagnostic tests to speed development of what could be the first test to detect Alzheimer's in its early stages. If all goes well, the first commercial version of the test could be available in 12 to 18 months, possibly enabling patients to try to slow progression of the increasingly common disease, said Dr. Daniel Alkon, scientific director of the Blanchette Rockefeller Neurosciences Institute. "This may be a way of monitoring how effective a treatment is for Alzheimer's disease" as well, through periodic retesting once scientists can develop a medicine to stop the mind-robbing disease, Alkon told The Associated Press in an exclusive interview Tuesday. Alkon's institute, based at West Virginia University and affiliated with Johns Hopkins University, on Wednesday announced a multimillion-dollar contract with Inverness Medical Innovations Inc. of Waltham, Mass. Inverness will fund development of the Alzheimer's test and future improvements, including an eventual home version, for at least three years. The test works by detecting abnormal function of a protein that has been shown to be involved in memory storage, Alkon said. © CBC 2009

Keyword: Alzheimers; Learning & Memory
Link ID: 12891 - Posted: 06.24.2010

By Tina Hesman Saey Even neurons need quiet time. A new study shows the brain cells take time out while you sleep, preventing you from waking up at the drop of a hat or other nonthreatening object. For decades, scientists have been measuring electrical activity in the brain during sleep with electroencephalograms, or EEGs. Researchers easily recognize the hallmark dips and blips of each stage of sleep, but what brain cells are doing to produce the signals hasn’t been apparent. Now, a new study in the May 22 Science shows that a prominent electrical signal of slow-wave sleep, called the K-complex, indicates downtime for neurons. The quiet periods could help people ignore distractions, such as sounds and touches, and stay asleep, the researchers report. K-complexes appear as sharp dips in EEG tracings. The events happen shortly after a person falls asleep, during a period of slow-wave sleep when people are transitioning from light sleep into the heaviest periods of deep sleep. Such dips correspond to a quieting of brain cell activity in animals. Though the traditional electrodes used in EEG measure activity over large areas on the surface of the outer layer of the human brain — the cortex — no one really knew what the signals indicated about fine-scale brain activity in the cortex’s deeper layers. © Society for Science & the Public 2000 - 2009

Keyword: Sleep
Link ID: 12890 - Posted: 06.24.2010

by Priya Shetty Doubt is being cast on the true role of brain neurons that are said to explain empathy, autism and even morality. Mirror neurons fire both when we perform an action and when we see someone else doing it. The theory is that by simulating action even when watching an act, the neurons allow us to recognise and understand other people's actions and intentions. However, Alfonso Caramazza at Harvard University and colleagues say their research suggests this theory is flawed. Neurons that encounter repeated stimulus reduce their successive response, a process called adaptation. If mirror neurons existed in the activated part of the brain, reasoned Caramazza, adaptation should be triggered by both observation and performance. To test the theory, his team asked 12 volunteers to watch videos of hand gestures and, when instructed, to mimic the action. However, fMRI scans of the participants' brains showed that the neurons only adapted when gestures were observed then enacted, but not the other way around. Caramazza says the finding overturns the core theory of mirror neurons that activation is a precursor to recognition and understanding of an action. If after executing an act, "you need to activate the same neurons to recognise the act, then those neurons should have adapted," he says. © Copyright Reed Business Information Ltd.

Keyword: Autism; Vision
Link ID: 12889 - Posted: 06.24.2010

Jennifer Viegas -- For years, fishermen in Alaska wondered why their catches were mysteriously disappearing, and now remarkable new footage shows a sperm whale adroitly "stealing" fish on lines without leaving behind any tell-tale evidence, save for its candid camera appearance. The video presents the first known footage of a male sperm whale eating in the wild. Since it includes ear-splitting sounds made by the feeding whale, the video is also helping scientists better understand how the marine giants vocalize, allowing researchers to estimate population sizes based on whale chatter. "We definitely did a high-five when we saw the video," project leader Aaron Thode of Scripps Institution of Oceanography told Discovery News. "It was a fist-pumping moment." With the help of black cod longline fisherman Kendall Folkert, Thode and colleague Delphine Mathias deployed video cameras and acoustic recorders like flying kites on Folkert's fishing lines off Sitka, Alaska, at a depth of 328 feet. Longline operations consist of a main fishing line draped across the ocean and fastened with shorter lines bearing baited hooks. Marine mammals often avoid anything that looks foreign in their environment, so the researchers camouflaged their setup with "fake tangled rope" and other disguises. One male sperm whale fell for the camera trap. © 2009 Discovery Communications, LLC.

Keyword: Intelligence; Evolution
Link ID: 12888 - Posted: 06.24.2010

by Holly Hight OREGON, U.S.: The high-pitched, maniacal 'laugh' of the hyena is not used by all individuals equally, but mostly by subordinates as a sign of frustration. "The hyena's laugh is a multi-informative signal," said Nicholas Mathevon, a biologist at the University of Jean Monnet, in Saint-Etienne, France, who studied captive hyenas, recording their laughs and subjecting them to sophisticated acoustical studies. The hyena has up to 20 vocalisation types, but only two had previously been studied. One is a 'whoop', used as a long-distance call, while the other is a groan, used for communication over short ranges. Mathevon found that the laugh tends to occur when subordinate animals are attacked or chased away by dominant hyenas during feeding times and "is mainly emitted when [the animal] is frustrated," said Mathevon, who presented his results this week at the Acoustics Society of America's annual conference in Portland, Oregon. The spotted hyena (Crocuta crocuta), which is found widely across Africa, has a complex social structure – as complex as the social systems of primates such as baboons and macaques. It is a savage hierarchy; subordinates are frequently attacked and denied access to food and mates. ©2007 Luna Media Pty Ltd,

Keyword: Animal Communication; Language
Link ID: 12887 - Posted: 06.24.2010

by Ewen Callaway Do you think you're smarter than most? Chances are, your children will feel the same way about themselves. A new study of thousands of twins suggests that intellectual confidence is genetically inherited, and independent from actual intelligence. Moreover, these genetic differences predict grades in school, says Tomas Chamorro-Premuzic, a psychologist at Goldsmiths University in London, whose team found that 7- to 10-year-old children who achieved the best marks in school tended to rate their own abilities highly, even after accounting for differences due to intelligence and environment. Psychologists have long known that intelligence isn't the only predictor of scholastic achievement and that intellectual confidence does a good a job of predicting grades as well. "There has been a very, very big lobby within educational psychology against the notion of IQ," says Chamorro-Premuzic. "And part of this lobby has been based on the idea that self-perceptions matter more than actual ability." Most of these researchers assumed that environmental factors – the influence of parents, teachers and friends – explained why some students think more of their abilities than others. © Copyright Reed Business Information Ltd

Keyword: Emotions; Intelligence
Link ID: 12886 - Posted: 06.24.2010

By Rebecca Morelle Rooks have a remarkable aptitude for using tools, scientists have found. Tests on captive birds revealed that they could craft and employ tools to solve a number of different problems. The findings, published in the Proceedings of the National Academy of Sciences, came as a surprise as rooks do not use tools in the wild. Despite this, the UK team said the birds' skills rivalled those of well-known tool users such as chimpanzees and New Caledonian crows. Dr Nathan Emery, from Queen Mary, University of London, an author of the paper, said: "The study shows the creativity and insight that rooks have when they solve problems." The scientists focused on four captive rooks: Cook, Fry, Connelly and Monroe, and discovered that the birds were able to use tools in a number of ways to solve a variety of problems. For example, the birds were presented with a vertical tube, running down to a trap-door with an out-of-reach worm perched upon it, as well as a number of different-sized stones placed nearby. The scientists discovered that the rooks would select the largest stone, which was heavy enough to push open the trap-door when dropped and release the snack. And when given a selection of different-shaped stones, some of which could fit into the tube some of which could not, the rooks opted for a tool that would give them access to the treat. Lead author Christopher Bird, from Cambridge University, said: "We have found that they can select the appropriate tools out of a choice of tools and they show flexibility in the types of tools they use." (C)BBC

Keyword: Intelligence; Evolution
Link ID: 12885 - Posted: 05.26.2009

By JANE E. BRODY Edward Ferguson, a civil engineer living in Vancouver, Wash., retired at age 65 from a job handling multimillion-dollar contracts. Five years later he could not balance a checkbook, walk without falling, drive a car, control his bladder or recognize his granddaughter. Instead of the active retirement he had anticipated, Mr. Ferguson, now 74, thought he would spend the rest of his life in a wheelchair, incontinent and struggling with dementia. Ten doctors were unable to tell him what was wrong, but an Internet search by his daughter found a condition that seemed to match his symptoms: normal pressure hydrocephalus, or N.P.H. The disorder involves a build-up of spinal fluid in the ventricles of the brain, causing pressure on nerves that control the legs, balance, bladder and cognitive function. “It’s as if the brain has reverted to babyhood,” Dr. Michael Kaplitt, a neurosurgeon at NewYork-Presbyterian Hospital/Weill Cornell Medical Center, said in an interview. “Like babies, people with N.P.H. walk slowly with feet wide apart, they are incontinent and have no memory.” Dr. Kaplitt calls it “a classic triad of symptoms” that should alert doctors to the possibility of N.P.H. Yet the condition is frequently misdiagnosed as dementia, Alzheimer’s disease, Parkinson’s disease or a spinal problem. Or it is attributed to age — nearly all who are affected are over 55. Copyright 2009 The New York Times Company

Keyword: Alzheimers; Movement Disorders
Link ID: 12884 - Posted: 06.24.2010

By ANAHAD O’CONNOR For almost a century, eye exercises have been promoted as a way to strengthen vision and ease nearsightedness and astigmatism, much like exercise for the body trims fat and improves health. Some of the most popular techniques include eye-hand coordination drills, eye movement routines and focusing on blinking lights. The techniques are widely promoted online and advocated by various companies, some even claiming that they can reduce the need for glasses and ease learning disabilities. But several studies have concluded that many of these do-it-yourself techniques are baseless. One of the latest studies, published in 2009, found little evidence in support of vision exercises that supposedly slow or reduce myopia, ease dyslexia and correct conditions caused by physiological problems, like blurred vision. A similar conclusion had been reached in a 2005 report that reviewed 43 previous studies, finding “no clear scientific evidence” for most of the methods reviewed. But there are some areas of vision therapy that have been scientifically validated, including one called orthoptics. In this therapy, eye doctors prescribe exercises that can relieve double vision, focus problems and conditions like strabismus, also known as crossed eyes. Orthoptics can treat convergence insufficiency, in which the eyes have trouble working together. It affects as many as 1 in 5 people, but with the right exercises it can be all but cured, studies show. Copyright 2009 The New York Times Company

Keyword: Vision
Link ID: 12883 - Posted: 06.24.2010

Scientists believe they have made a breakthrough in the treatment of a severe muscle disease that causes floppy baby syndrome. Most babies born with the rare disorder are severely paralysed and the majority die before the age of one. The Australian team was able to cure affected mice by replacing a missing muscle protein. A UK expert said the findings, in the Journal of Cell Biology, could lead to improved movement for affected babies. The team focussed on proteins called actins. A gene called ACTA1 controls the production of actin in skeletal muscles. It is key to allowing muscles to contract, but children with this disease have flawed versions of the gene and so the protein is not produced. However, the scientists had seen that some children with floppy baby syndrome were not totally paralysed at birth. When these children were studied, it was found that heart actin - another form of the protein - was "switched on" in their skeletal muscles, when that would not normally be the case. Heart actin is found in skeletal muscles while the baby is developing in the womb, but has almost completely disappeared by birth. The researchers found it was possible to cure mice genetically engineered to have the recessive form of the muscle disorder by replacing the missing skeletal muscle actin with heart actin. Dr Kristen Nowak, of the Western Australian Institute for Medical Research, who led the study, said: "The mice with floppy baby syndrome were only expected to live for about nine days, but we managed to cure them so they were born with normal muscle function, allowing them to live naturally and very actively into old age. This is an important step towards one day hopefully being able to better the lives of human patients - mice who were cured of the disease lived more than two years, which is very old age for a mouse." (C)BBC

Keyword: Movement Disorders; Muscles
Link ID: 12882 - Posted: 05.26.2009

By Shankar Vedantam Soon after her sister committed suicide, Caroline Downing started doing poorly at school. During math tests she would freeze up, and she found her mind wandering constantly. Officials at St. Andrew's Episcopal School in Potomac gently suggested that the high school sophomore get a mental health screening. The idea of a psychiatric evaluation sent chills down the spine of Caroline's mother, Mathy Milling Downing, who believed that her younger daughter, Candace, had committed suicide because of an adverse reaction linked to a psychiatric drug -- the antidepressant Zoloft. Shortly after Candace's death, the Food and Drug Administration placed black-box warnings on several antidepressants to say they elevated suicidal thinking among some children. If Caroline were going to get the same kind of mental health care as Candace, Downing wanted no part of it. Downing's family offers a powerful case study into the pros and cons of new guidelines recommending widespread screening of adolescents for mental disorders: Last month, the U.S. Preventive Services Task Force, a federal group that makes public health recommendations, said that all adolescents between ages 12 and 18 should be screened for major depression. In March, the Institute of Medicine, which advises Congress on scientific matters, told policymakers that early screening was key to reducing the financial and medical burden of mental disorders in the United States. Downing said she agreed to have her older daughter screened because the child was obviously in distress, but she told school officials that if an evaluation led to a prescription for medications, she would refuse to go along. © 2009 The Washington Post Company

Keyword: Depression; Development of the Brain
Link ID: 12881 - Posted: 06.24.2010

By RONI CARYN RABIN A few years ago, shortly after she moved to New York City, one of her friends pointed out a young man standing on the other side of the room at a party. Ms. Jarett took one look and said, “Oh, I know who he is — I went to Hebrew school with him in fourth grade.” At the time, Ms. Jarett, who is now 38, had not seen the boy in nearly two decades, since they were both children. In a study published in April, Harvard scientists coined the term “super-recognizers” to describe people like Ms. Jarett who have an uncanny ability to recognize and remember faces. The brain’s ability to identify faces varies from person to person: while a small minority are unable to recognize others at all, the “super-recognizers” have an extraordinary talent for recollection, occupying the extreme end of the face-recognition spectrum, said Richard Russell, a postdoctoral researcher in psychology at Harvard University and lead author of the paper, published in Psychonomic Bulletin & Review. Dr. Russell assessed the recognition abilities of four subjects, including Ms. Jarett, who identified themselves as having a knack for remembering faces. In one exam, they were asked to identify celebrities through 56 photographs taken before they achieved fame or when they were children. Copyright 2009 The New York Times Compan

Keyword: Miscellaneous
Link ID: 12880 - Posted: 06.24.2010

Melissa Dahl Five-inch stilettos, too-heavy handbags, a wedding dress that seemingly weighed as much as a small child — Parmeeta Ghoman admits she’s no stranger to suffering for fashion. “I’m the kind of person who buys shoes two sizes too small just because they’re cute — and they’re on sale,” says Ghoman, who's 28 and lives outside of San Francisco. But when she wore a pair of super-tight skinny jeans to dinner with friends in December, she noticed an odd tingly sensation running up and down her thighs. And when she got up to walk around, things got weirder. She felt like she was almost "floating," because she couldn't feel her legs. “It felt really strange — it felt like my leg had gone to sleep,” Ghoman says. Ghoman’s skin-tight denim may have caused a temporary bout of a nerve condition called meralgia paresthetica, also known as “tingling thigh syndrome.” The condition can happen when constant pressure — in Ghoman's case, from the skin-tight denim — cuts off the lateral femoral cutaneous nerve, causing a numb, tingling or burning sensation along the thigh. Typically, sufferers of the nerve condition include construction workers or police officers with heavy, low-slung belts, pregnant women or obese people; it also can result from a pulled-tight seat belt in a car accident. But over the last several years, experts say they’ve been seeing more young women at a healthy weight complain of symptoms. The culprit: too-tight jeans. © 2009 msnbc.com

Keyword: Pain & Touch
Link ID: 12879 - Posted: 06.24.2010

By JOHN MARKOFF Mountain View, Calif. — It’s summertime and the Terminator is back. A sci-fi movie thrill ride, “Terminator Salvation” comes complete with a malevolent artificial intelligence dubbed Skynet, a military R.&D. project that gained self-awareness and concluded that humans were an irritant — perhaps a bit like athlete’s foot — to be dispatched forthwith. The notion that a self-aware computing system would emerge spontaneously from the interconnections of billions of computers and computer networks goes back in science fiction at least as far as Arthur C. Clarke’s “Dial F for Frankenstein.” A prescient short story that appeared in 1961, it foretold an ever-more-interconnected telephone network that spontaneously acts like a newborn baby and leads to global chaos as it takes over financial, transportation and military systems. Today, artificial intelligence, once the preserve of science fiction writers and eccentric computer prodigies, is back in fashion and getting serious attention from NASA and from Silicon Valley companies like Google as well as a new round of start-ups that are designing everything from next-generation search engines to machines that listen or that are capable of walking around in the world. A.I.’s new respectability is turning the spotlight back on the question of where the technology might be heading and, more ominously, perhaps, whether computer intelligence will surpass our own, and how quickly. Copyright 2009 The New York Times Company

Keyword: Intelligence; Robotics
Link ID: 12878 - Posted: 06.24.2010

Scientists have produced more evidence that vitamin D has an important role in keeping the brain in good working order in later life. A study of over 3,000 European men aged 40-79 found those with high vitamin D levels performed better on memory and information processing tests. The University of Manchester team believe vitamin D may protect cells or key signalling pathways in the brain. The study features in the Journal of Neurology Neurosurgery and Psychiatry. It follows research published in January which suggested that high levels of vitamin D can help stave off the mental decline that can affect people in old age. The latest study focused on men from eight cities across Europe. Their mental agility was assessed using a range of tests, and samples were taken to measure levels of vitamin D in their blood. Men with high vitamin D levels performed best, with those who had the lowest levels - 35 nmol/litre or under - registering poor scores. The researchers said the reason why vitamin D - found in fish and produced by sun exposure - seemed to aid mental performance was unclear. They suggested it might trigger an increase in protective hormonal activity in the brain. However, the only data to back this up so far comes from animal studies. There is also some evidence that vitamin D can dampen down an over-active immune system. Alternatively, it may boost levels of antioxidants that in effect detoxify the brain. The researchers stressed that many people, particularly in older age, were vitamin D deficient. (C)BBC

Keyword: Alzheimers; Hormones & Behavior
Link ID: 12877 - Posted: 05.25.2009