Kerri Smith Researchers have found the internal 'metronome' that controls how fast birds sing by cooling small areas of the zebra finch brain. The finding clarifies how birds keep time and could even shed light on how humans regulate their speech, or make music. Michael Long and Michale Fee at the Massachusetts Institute of Technology in Cambridge came up with a device that allowed them to cool down a part of the zebra finch brain called the high vocal centre (HVC). This centre consists of two small regions, one in each hemisphere, and is located towards the back of the bird's forebrain, close to the surface of the brain. The centre is involved in song production but its exact function was not known. The researchers implanted two thin cooling elements made of gold into the brains of adult zebra finches so that they lay over the two regions forming the HVC, which are each just 1 millimetre by 2 millimetres across. They then cooled the regions very precisely using a thermoelectric property called the Peltier effect, in which an electric current is used to transfer heat from one end of the element to the other. Cooling the HVC by 6.5 ºC slowed down the birds' song by up to 45% and had little effect on its other features, such as pitch or the order of the notes1 (see 'Cool songs'). The team then cooled another region involved in singing, called the robust nucleus of the arcopallium, or RA, but didn't see the same effect. This confirms that the HVC is indeed serving as the birds' metronome, the researchers say. The results are published in Nature. © 2008 Nature Publishing Group

Keyword: Language; Sexual Behavior
Link ID: 12222 - Posted: 06.24.2010

by Ewen Callaway Everyone loves a pretty face - except those women who might see it as a threat. With eyes on the competition, women of childbearing age rate other attractive women consistently lower than women who have entered menopause, according to a new study. "It's almost as if they're putting down other attractive women," says Benedict Jones, a psychologist at Aberdeen University, UK, who led the study of 97 middle-aged women. Numerous studies have looked at how fertility affects women's preferences for men's faces, bodies, voices, and even sweaty shirts. Yet few researchers have flipped the coin to examine how fertility changes competition for mates within sexes, says Jones. He and his colleagues showed pre- and post-menopausal women pictures of men and women, digitally manipulated to make them more masculine or more feminine looking. Their software systematically enhances male features such as a wide jaw and heavy brow or female attributes such as wider eyes and more arched eyebrows. "It's not going into Photoshop and mucking about to make the jaw a few pixels wider and the eyes a few pixels bigger," he says. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior
Link ID: 12221 - Posted: 06.24.2010

WASHINGTON - It’s a delicate and daring experiment: Could doctors switch a leg nerve to make it operate the bladder instead? Families of a few U.S. children whose spina bifida robs them of the bladder control that most people take for granted dared to try the procedure — and early results suggest the surgery indeed may help, in at least some patients. With the technique, pioneered in China, the kids are supposed to scratch or pinch their thigh to signal the bladder to empty every few hours. But surprisingly, some youngsters instead are starting to feel those need-to-go sensations that their birth defect had always prevented. “It feels like this little chill kind of thing in me,” marvels 9-year-old Billy Kraser of Scranton, Pa. “When he goes in there and he’s dry and he’s clean, it’s such a triumph,” adds his mother, Janice Kraser. “I’ll hear him going, ‘Yesss!”’ The U.S. pilot study consists of just nine spina bifida patients and still is tracking how they fare — no one is finished healing yet. But already desperate families are lining up for a chance at this nerve rerouting, even as William Beaumont Hospital in Royal Oak, Mich., is trying to raise money to expand the study and provide better evidence. © 2008 Microsoft

Keyword: Regeneration
Link ID: 12220 - Posted: 06.24.2010

By Shankar Vedantam Steve Newman had suffered from major depression from the time he was 13. He tried innumerable treatments: psychotherapy and medications. Approaching 60, single by necessity and friendless by choice, he decided his train had only two stops left before suicide. One option was shock therapy, formally known as electroconvulsive therapy, or ECT. The controversial technique has been shown to be effective in treating depression, but it involves inducing seizures in patients. Memory loss is a common side effect. Newman was not looking forward to it. Newman was working in Florida as an insurance agent when he heard about the other option. It sounded like science fiction, or just kooky: Scientists in this country and overseas were experimenting with the use of high-power magnets to cure depression, using a technique known as transcranial magnetic stimulation, or TMS. "I would have jumped into a volcano to get better; my life was just unbearable," Newman said. "I was at the point in my life where I did not have a lot of choice. I decided I would try TMS and then ECT, and if neither of them worked, I was going to consider suicide." Newman gave up his job in Florida and in 2005 moved to Philadelphia, where he signed up for the magnetic therapy trial at the University of Pennsylvania. Weeks after the treatments began, Newman said, he woke up one morning and found that his depression had vanished. © 2008 The Washington Post Company

Keyword: Depression
Link ID: 12219 - Posted: 06.24.2010

By BENEDICT CAREY Two scientists, drawing on their own powers of observation and a creative reading of recent genetic findings, have published a sweeping theory of brain development that would change the way mental disorders like autism and schizophrenia are understood. The theory emerged in part from thinking about events other than mutations that can change gene behavior. And it suggests entirely new avenues of research, which, even if they prove the theory to be flawed, are likely to provide new insights into the biology of mental disease. At a time when the search for the genetic glitches behind brain disorders has become mired in uncertain and complex findings, the new idea provides psychiatry with perhaps its grandest working theory since Freud, and one that is grounded in work at the forefront of science. The two researchers — Bernard Crespi, a biologist at Simon Fraser University in Canada, and Christopher Badcock, a sociologist at the London School of Economics, who are both outsiders to the field of behavior genetics — have spelled out their theory in a series of recent journal articles. “The reality, and I think both of the authors would agree, is that many of the details of their theory are going to be wrong; and it is, at this point, just a theory,” said Dr. Matthew Belmonte, a neuroscientist at Cornell University. “But the idea is plausible. And it gives researchers a great opportunity for hypothesis generation, which I think can shake up the field in good ways.” Copyright 2008 The New York Times Company

Keyword: Autism; Genes & Behavior
Link ID: 12218 - Posted: 06.24.2010

By ANAHAD O’CONNOR High school textbooks call it the tongue map — that colorful illustration that neatly divides the human tongue into sections according to taste receptors. There is the tip of the tongue for sweet, the sides for sour and salty, and the back of the tongue for bitter. But recent studies show that while scientists still have much to learn about receptors, the map, at least, is wrong What is known is that there are at least five basic tastes: sweet, sour, salty, bitter and the most recently discovered, umami. This last flavor, which means “savory” in Japanese, can be detected in miso, soy sauce and other Asian foods, particularly those that contain monosodium glutamate. And scientists suspect that there are receptors for other flavors as well. In a study published in the journal Nature in 2006, a team of scientists reported that receptors for the basic tastes are found in distinct cells, and that these cells are not localized but spread throughout the tongue. That said, other studies suggest that some parts may be more sensitive to certain flavors, and that there may be differences in the way men and women detect sour, salty and bitter flavors. THE BOTTOM LINE Receptors for different tastes are not confined to certain parts of the tongue. Copyright 2008 The New York Times Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 12217 - Posted: 06.24.2010

By Billy Baker Bevil Conway, an artist turned neuroscientist, was sitting in front of a laptop computer recently at Harvard Medical School showing off one of his latest discoveries. Small squares of color flashed rapidly on the screen - red, yellow, green - until suddenly, as the screen showed a square of deep purple, the computer's speakers crackled with electrical static. If you ask why an artist would delve into the labyrinthine, and largely unknown, workings of the brain, the look of satisfaction on Conway's face as he leaned back in his chair said it all. The static on the speakers is the electrical signal recorded from a single neuron in a monkey's brain, a neuron that only turned on when the monkey was shown deep purple on a monitor. "When you discover something new about the brain, it's intoxicating," said Conway. "That's the first deep purple recording in history. Philosophers have been arguing for hundreds of years whether color is encoded in the brain or is external. What's amazing is that this is in a monkey. They don't have language. When I learn something like this, I get the same feeling as when I make a painting that does something that would never have been done if I weren't around." Conway, 34, a native of Zimbabwe who is an assistant professor at Wellesley College and a visiting scientist at Harvard Medical School, started out as a visual artist. In exploring the techniques of art - why certain color combinations work; why line drawings are effective even though they have no external basis in nature; how movement can be conveyed in a two-dimensional media - he found a desire to understand the way vision and perception work in the brain itself.

Keyword: Vision
Link ID: 12216 - Posted: 11.11.2008

by John Seabrook The Western New Mexico Correctional Facility sits in high-desert country about seventy miles west of Albuquerque. Grants, a former uranium boomtown that depends heavily on prison work, is a few miles down the road. There’s a glassed-in room at the top of the prison tower, with louvred windows and, on the ceiling, a big crank that operates a searchlight. In a box on the floor are some tear-gas shells that can be fired down into the yard should there be a riot. Below is the prison complex—a series of low six-sided buildings, divided by high hurricane fences topped with razor wire that glitters fiercely in the desert sun. To the east is the snow-covered peak of Mt. Taylor, the highest in the region; to the west, the Zuni Mountains are visible in the blue distance. One bright morning last April, Dr. Kent Kiehl strode across the parking lot to the entrance, saying, “I guarantee that by the time we reach the gate the entire inmate population will know I’m here.” Kiehl—the Doc, as the inmates call him—was dressed in a blue blazer and a yellow tie. He is tall, broad-shouldered, and barrel-chested, with neat brown hair and small ears; he looks more like a college football player, which was his first ambition, than like a cognitive neuroscientist. But when he speaks, in an unexpectedly high-pitched voice, he becomes that know-it-all kid in school who intimidated you with his combination of superior knowledge and bluster. At thirty-eight, Kiehl is one of the world’s leading younger investigators in psychopathy, the condition of moral emptiness that affects between fifteen to twenty-five per cent of the North American prison population, and is believed by some psychologists to exist in one per cent of the general adult male population. (Female psychopaths are thought to be much rarer.) © 2008 CondéNet

Keyword: Aggression; Emotions
Link ID: 12215 - Posted: 06.24.2010

Injuries in very young children are associated with later diagnosis of attention deficit hyperactivity disorder, UK research suggests. A study of 62,000 children shows both head and burn injuries before the age of two are linked with almost double the risk of ADHD diagnosis by age 10. It suggests injuries in general are an early sign of ADHD behaviour. The British Medical Journal study may help GPs spot children who need specialist referral, experts said. Previous research has suggested mild brain injury is associated with behavioural changes in children. The researchers said that although a link between head injury and ADHD had been shown it was not clear which comes first. In the latest study, a team of UK and US researchers, predicted that they would find higher rates of ADHD diagnosis in children who had been treated for a head injury when they were younger than in those who had burn injuries. Using data from more than 300 general practices from between 1988 to 2003 they found that both types of injuries were associated with greater rates of ADHD diagnosis than children who had no injuries. The study also found that children who had a head injury after the age of two had a greater likelihood of being diagnosed with ADHD before their 10th birthday among all three groups. Children who go on to develop ADHD may exhibit more risk-taking behaviours as young children and are therefore more likely to experience early injuries, the researchers suggest. There is considerable debate over the cause of ADHD. The National Institute for Health and Clinical Excellence guidelines state that risk factors for ADHD are likely to interact and that although genetics is important, environmental factors such as injury or maternal smoking may also contribute. (C)BBC

Keyword: ADHD; Brain Injury/Concussion
Link ID: 12214 - Posted: 11.08.2008

By Mark Leyner and Dr. Billy Goldberg Imagine an accidental bop on the head changed your accent from the grating stridence of Fran Drescher to the dulcet, euphonious tones of, say, Kate Winslet. Or if you’re a man, what if a whack to the forehead transformed your speech from something out of Homer Simpson's pie-hole to the adorably urbane voice of Stewie Griffin from “Family Guy?” That kind of bizarre voice change happened for real to a woman from Washington’s Olympic Peninsula. Recent newspaper reports and a cable TV show featured CindyLou Romberg, who split her head from front to back after falling out of a moving car in 1981. Despite the serious brain injury, after her awful headaches and lingering back pain abated, she resumed a normal life as a caregiver and motorcycle enthusiast. Until her back started bothering her again about a year ago. After visiting a local chiropractor, Romberg soon began speaking gibberish.When she began speaking normally again, she had a German accent, tinged with what some friends thought was vaguely French or Russian. This strange accent was coming from an American woman who had never studied a foreign language, nor been to any foreign country, except Canada. © 2008 Microsoft

Keyword: Language; Brain Injury/Concussion
Link ID: 12213 - Posted: 06.24.2010

Sharon Begley The tragedy of autism is compounded by one fact that makes desperate parents wish they could turn back the hands of time: symptoms of the neurodevelopmental disorder typically show up when a child is 2 or 3 or even older, but by then it may be too late to prevent or reverse whatever glitches in brain development (still pretty much a mystery) underlie the disease. It is even on the late side for getting a child the behavioral interventions and special education that might mitigate some of the worst symptoms. If scientists at the M.I.N.D. Institute of the University of California, Davis, are right, however, there may be a reliable warning sign of autism much earlier: how a child plays with his or her toys at the tender age of 12 months. In particular, scientists led by Sally Ozonoff will report in the journal Autism (it’s the October issue, but not out yet; keep checking the web site), children who were later diagnosed with autism were more likely to spin, repetitively rotate, stare at and look out of the corners of their eyes at toys such as a rattle. There is a big research effort aimed at picking up the earliest harbingers of autism. One of the most promising discoveries came in 2003, when researchers led by neuroscientist Eric Courchesne of the University of California, San Diego, concluded that an odd pattern of skull growth might be a tip to autism, as they described in a paper in the Journal of the American Medical Association. Children with autism, the scientists found, had a smaller head circumference at birth than healthy babies, and by 6 to 14 months their head circumference was in the 84th percentile, a huge increase and greater than the rate of increase in healthy children. © 2008 Newsweek, Inc.

Keyword: Autism; Development of the Brain
Link ID: 12212 - Posted: 06.24.2010

By GREG BISHOP Using the “contact us” tab on the organization’s Web site, an adult who lived in the area wanted to volunteer and work closely with children. The man knew what they were going through. His first seizure came on Christmas Eve during his freshman year of high school. The name at the bottom of the note nearly caused the employee reading it to fall from the chair. “Sincerely, Alan Faneca,” it said. The foundation has four offices, all in the heart of Steelers country, and here was Faneca, the Steelers’ perennial Pro Bowl guard, asking to volunteer, unprompted, for no reason other than that he had excelled with epilepsy, not in spite of it. “Very few people in the public eye who have epilepsy are willing to publicly talk about it,” said Judy Painter, the foundation’s executive director. “Alan gave so much hope to other people — people I don’t think he ever expected he would help.” Like Nick Cardello, 62, from Pittsburgh. Cardello grew up watching Mean Joe Greene and Lynn Swann and Terry Bradshaw, Steelers who were so good, he said, “you couldn’t not watch them.” Before Faneca went to the Jets this off-season, he was Cardello’s favorite player, a punishing left guard whose lack of glitz and glamour suited Steelers fans. Copyright 2008 The New York Times Company

Keyword: Epilepsy
Link ID: 12211 - Posted: 06.24.2010

Amelia Hill, social affairs correspondent The most severe form of postnatal depression, which affects one in 500 new mothers and has been linked to suicide and infanticide, could be genetic, according to new research. It is also claimed, in a separate piece of research, that thousands more women could suffer postnatal depression than currently thought, with up to 17,250 late-onset cases a year in the UK going undetected. It was believed that the mood disorders affecting up to 75 per cent of new mothers were caused by the women's circumstances, personality and hormonal changes. But according to a study by Cardiff University, Birmingham University and Trinity College, Dublin, funded by medical charity the Wellcome Trust, the most severe form of postnatal depression - postpartum psychosis - has a genetic cause. The study is now working to isolate the gene, which will enable doctors to identify and treat high-risk women before they fall ill. New mothers can suffer from a spectrum of mood disorders. But while most women suffer 'baby blues' - a short period of tearfulness and tiredness after childbirth - postnatal depression is a more severe, long-lasting condition which affects 10 to 15 per cent of women and can prevent mothers bonding with their babies and cause suicidal thoughts. If left untreated, it can affect the short or long-term development of the baby. © Guardian News and Media Limited 2008

Keyword: Depression; Genes & Behavior
Link ID: 12210 - Posted: 06.24.2010

By Greg Miller When it comes to the neurobiology of memory, the hippocampus typically gets most of the credit. But although this brain region is crucial for recording new memories, like the name of someone you just met at a bar, people with a damaged hippocampus can still recall memories from days of old. Many neuroscientists believe this is because lasting memories get shifted to the cerebral cortex for permanent storage. Little is known about how this might happen, but a study in today's issue of Science provides some clues. The new study, by neuroscientists Kaori Takehara-Nishiuchi and Bruce McNaughton, then at the University of Arizona, Tucson, builds on a 2003 study on memory by Takehara-Nishiuchi. She and colleagues trained rats to blink when they heard a tone signaling a mild shock to the eyelid. When the researchers removed the hippocampus a day after the training, rats no longer remembered to blink when they heard the tone, but removing the hippocampus 4 weeks after the training session had no effect: The rats still blinked. Conversely, removing the medial prefrontal cortex (mPFC) a day after the training caused no memory lapses, but removing this region 4 weeks later made the rats forget all about the tone. The findings suggested that whereas the hippocampus is essential for short-term memory storage, the mPFC is critical for long-term storage. To investigate further, Takehara-Nishiuchi used hair-thin electrodes to record the activity of individual neurons in the mPFC of rats. This time the animals received more complex training. Over the course of 2 months, the rats heard the tone in two different contexts--in a square enclosure, where the tone always preceded a shock; or in a circular enclosure, where the tone and shock occurred randomly. By 2 weeks, rats had learned to blink when they heard the tone inside the square enclosure, where it reliably predicted a shock. But they ignored the tone inside the circular enclosure, where it did not. At the same time, about a quarter of the rat's mPFC neurons fired at higher rates when the tone sounded inside the square enclosure. This selective firing developed gradually over the first 2 weeks of training and persisted for the rest of the training period. The time course of this change in neural firing is similar to the time course of memory consolidation in the mPFC suggested by Takehara-Nishiuchi's 2003 study. © 2008 American Association for the Advancement of Science.

Keyword: Learning & Memory
Link ID: 12209 - Posted: 06.24.2010

By Laura Sanders When it comes to sensory information detected by the body, pain is king, and itch is the court jester. But that insistent, tingly feeling—satisfied only by a scratch—is anything but funny to the millions of people who suffer from it chronically. Garden-variety itches related to histamine, like the kind caused by an angry rash of chicken pox or poison ivy, annoy everyone, but most can be subdued with drugs like Benadryl. But another type of itch is not mollified by these drugs, and therein lies the rub. Pathological itch — called the “itch that laughs at Benadryl” by neuroscientist and itch investigator Glenn Giesler Jr. of the University of Minnesota—is no joke. Not often pursued by scientists who look at sensation, itch research has lagged far behind investigations of other bodily cues. But in recent years, scientists have begun studying pathological itch seriously. This year researchers found nerve fibers—long, thin strands that carry information from the outer skin to the spinal cord and ultimately, the brain—built to detect this often-devastating type of itch. The new results show that it has its own pathway to the brain. “That’s the hottest topic in the field right now, the idea of different pathways for different itches,” says Earl Carstens, a neurobiologist at the University of California, Davis who studies the details of how these itches travel to the brain. The discovery of these fibers has also led some researchers to rethink the relationship between pain and itch. © Society for Science & the Public 2000 - 2008

Keyword: Pain & Touch
Link ID: 12208 - Posted: 06.24.2010

French scientists say they have found a drug that tricks the body into burning off fat even when on a high-fat diet. The University of Louis Pasteur team found the drug protected mice against weight gain and insulin resistance. The drug SRT1720 - a chemical cousin of red wine extract resveratrol - targets the protein SIRT1, which is thought to combat ageing, Cell Metabolism reports. UK obesity experts said new drug treatments were needed but should be used alongside lifestyle changes. About a quarter of men and a third of women in the UK are overweight, according to government statistics. A change in diet and an increase in physical exercise can shift excess weight, but can be hard for many to maintain. With the removal of the anti-obesity pill rimonabant, also known as Acomplia, from the market amid safety concerns, fewer drug options exist. The French team from the University Louis Pasteur became interested in the SIRT1 protein after earlier studies showing resveratrol countered some effects of a high-calorie diet via SIRT1. But tests in mice suggested gallons of wine would be necessary for humans to stand a chance of getting the same benefits. The scientists turned their attention to creating a more potent drug that would specifically target SIRT1. They found that a low dose of SRT1720 partially protected mice from gaining weight on a high-fat diet after 10 weeks of treatment. The drug worked by shifting the metabolism to a fat-burning mode that normally takes over only when energy levels are low. At higher doses, the drug completely prevented weight gain. It also improved the rodents' blood sugar tolerance and insulin sensitivity, which are important for warding off diabetes. (C)BBC

Keyword: Obesity
Link ID: 12207 - Posted: 11.06.2008

David Robson They've been used to explain autism, empathy and why porn turns us on. Now some of the past findings that mirror neurons have been said to explain have been called into question by new research which suggests that these past investigations have not looked closely enough. Mirror neurons are brain cells that fire both when performing an action, and when the brain is observing that action being performed by someone else. Because of this, they have been a focus of keen interest among scientists looking for the neurological roots of things like empathy or imitation, and even morality. They have been directly observed in monkeys by measuring the firing of single neurons in the brain. In humans, mirror neurons can't be observed directly, so most studies have instead looked for them by taking fMRI scans of subjects performing and observing various activities, and then finding the regions of the brain that light up in both situations. Now Ilan Dinstein from New York University has cast doubt on these studies. He claims that they haven't examined these regions in fine enough detail: the neurons responsible for the increased activity when observing may be different from those that are active when performing, he says. Assigning them a role in autism and morality is premature, he concludes. © Copyright Reed Business Information Ltd

Keyword: Autism; Vision
Link ID: 12206 - Posted: 06.24.2010

By Michael Shermer Over the past few hundred years, as scientists have grappled with understanding the source of the amazing processing power in our skulls, they have employed a number of metaphors based on familiar technologies of their given era. The brain has been thought of as a hydraulic machine (18th century), a mechanical calculator (19th century) and an electronic computer (20th century). Today, early in the 21st century, we have another metaphor driven by the capabilities of the current technology—this time colorful images from modern brain scans. Evolutionary psychologists, for example, have conceptualized the brain as a Swiss Army knife, with a collection of specialized modules that have evolved to solve specific problems in our evolutionary history, such as language for communication, facial recognition to separate friends from foes, cheating detection to prevent free riders, risk taking to raise the odds of individual or group success, and even God to explain the world and to find individual happiness in thoughts of an afterlife. Many neuroscientists have employed the module metaphor to describe specific regions of the brain “for X,” with X being whatever happens to be the task given to subjects while a machine scans their brains. Such tasks might include selecting brand logos they prefer (say, Coke or Pepsi) or political candidates they would vote for (conservatives or liberals). Scientists often use metaphors such as these as aids in understanding and explaining complex processes, but this practice necessarily oversimplifies the intricate and subtle realities of the physical world. As it turns out, the role of those blobs of color that we see in brain images is not as clear-cut as we have been led to believe. © 1996-2008 Scientific American Inc.

Keyword: Brain imaging
Link ID: 12205 - Posted: 06.24.2010

By Jon Cohen Blonterstaping. Perplisteronk. Contramponist. People who have trouble remembering and repeating nonsense words like these have a common speech and language disorder called specific language impairment (SLI). Although SLI clearly runs in families, the genes responsible have been hard to pin down. Now, a group has found the first such gene, one that had been previously tied to a language disorder in autism. "This study is an important scratch on the surface of the genetics of language impairment," says Mabel Rice, a leading researcher of language disorders and genetics at the University of Kansas, Lawrence. Molecular neuroscientist Simon Fisher of the University of Oxford in the U.K. and his co-workers received international attention in 2001 when they discovered the first connection between a gene, FOXP2, and a speech and language disorder (ScienceNOW, 3 October 2001). They showed that a rare mutation in FOXP2 explains problems that beset several generations of a British family. Many researchers expected to find direct links between FOXP2 and more common language problems, but none surfaced. The reason is that FOXP2 is likely one of several genes that work in concert to support speech and language. Fisher's team knew that FOXP2 turned other genes on and off in the brain, so they investigated human neurons grown in the lab to see which parts of the genome were bound by FOXP2 protein. They quickly discovered that FOXP2 had a strong attraction for sections of DNA that controlled a gene called CNTNAP2, which codes for a protein that affects how neurons interact with each other during development, the team reports online today in the New England Journal of Medicine. © 2008 American Association for the Advancement of Science

Keyword: Language; Genes & Behavior
Link ID: 12204 - Posted: 06.24.2010

Jordan Lite Autism is more common in rainy, coastal areas of the Pacific Northwest than in drier, inland parts of three states in the region, according to new research that suggests a possible link between the brain disorder and precipitation. Autism was twice as common in the damp counties west of the Cascade Mountains than in those east of the range, which get four times less rain, the study in Archives of Pediatric and Adolescent Medicine shows. Kids in counties in California where rainfall was heavier also had higher rates of the disorder than children whose first three years of life were spent in drier weather. Autism causes impaired social interactions, delayed speech, and repetitive movements or behaviors. For unknown reasons, autism prevalence has surged over the past 30 years from an estimated one in 2,500 to one in 150 U.S. children, according to the Centers for Disease Control and Prevention (CDC). It's not clear why those rates are more elevated in damp areas — including states not in the study such as New Jersey, Massachusetts, Maine and Minnesota — but bad weather that keeps genetically vulnerable kids indoors could play a role, the study authors write. "Rates vary a lot from state to state — it doesn't seem to be random," says study-co author Michael Waldman, the Charles H. Dyson professor of management and a professor of economics at Johnson Graduate School of Management at Cornell University in Ithaca, N.Y. © 1996-2008 Scientific American Inc.

Keyword: Autism
Link ID: 12203 - Posted: 06.24.2010