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

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

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

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

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

Keyword: Depression
Link ID: 10346 - Posted: 06.24.2010

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

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

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

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

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

Keyword: Emotions
Link ID: 10343 - Posted: 06.24.2010

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

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

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

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

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

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

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

Keyword: Stroke
Link ID: 10339 - Posted: 06.24.2010

By Shankar Vedantam "You gotta see this!" Jorge Moll had written. Moll and Jordan Grafman, neuroscientists at the National Institutes of Health, had been scanning the brains of volunteers as they were asked to think about a scenario involving either donating a sum of money to charity or keeping it for themselves. As Grafman read the e-mail, Moll came bursting in. The scientists stared at each other. Grafman was thinking, "Whoa -- wait a minute!" The results were showing that when the volunteers placed the interests of others before their own, the generosity activated a primitive part of the brain that usually lights up in response to food or sex. Altruism, the experiment suggested, was not a superior moral faculty that suppresses basic selfish urges but rather was basic to the brain, hard-wired and pleasurable. Their 2006 finding that unselfishness can feel good lends scientific support to the admonitions of spiritual leaders such as Saint Francis of Assisi, who said, "For it is in giving that we receive." But it is also a dramatic example of the way neuroscience has begun to elbow its way into discussions about morality and has opened up a new window on what it means to be good. Grafman and others are using brain imaging and psychological experiments to study whether the brain has a built-in moral compass. The results -- many of them published just in recent months -- are showing, unexpectedly, that many aspects of morality appear to be hard-wired in the brain, most likely the result of evolutionary processes that began in other species. © 2007 The Washington Post Company

Keyword: Emotions
Link ID: 10338 - Posted: 06.24.2010

DURHAM, N.C. -- The use of 12 tone intervals in the music of many human cultures is rooted in the physics of how our vocal anatomy produces speech, according to researchers at the Duke University Center for Cognitive Neuroscience. The particular notes used in music sound right to our ears because of the way our vocal apparatus makes the sounds used in all human languages, said Dale Purves, the George Barth Geller Professor for Research in Neurobiology. It's not something one can hear directly, but when the sounds of speech are looked at with a spectrum analyzer, the relationships between the various frequencies that a speaker uses to make vowel sounds correspond neatly with the relationships between notes of the 12-tone chromatic scale of music, Purves said. The work appeared online May 24 in the Proceedings of the National Academy of Sciences. (Download at http://www.pnas.org/cgi/reprint/0703140104v1) Purves and co-authors Deborah Ross and Jonathan Choi tested their idea by recording native English and Mandarin Chinese speakers uttering vowel sounds in both single words and a series of short monologues. They then compared the vocal frequency ratios to the numerical ratios that define notes in music.

Keyword: Hearing; Language
Link ID: 10337 - Posted: 05.26.2007

Drinking four or more cups of coffee a day may cut the risk of having a painful attack of gout, say Canadian scientists. A University of British Columbia team found blood uric acid levels - which are linked to the condition - were lower in people who drank more coffee. But tea had no measurable effect, suggesting that the active ingredient was not caffeine. The work is published in the journal Arthritis Care and Research. Gout affects about 600,000 people in the UK, with numbers thought to be increasing in recent years. Its symptoms, which are often joint pains in the lower limbs, happen when uric acid crystallises out of the blood into the joints. Drinking too much beer, or eating too much red meat are thought to be to blame for many cases. The main way to tackle the condition is to take anti-inflammatory pills, change diet and drink more water, or in more severe cases, to take more powerful drugs to reduce uric acid levels in the blood. The latest research looked at the eating habits of 14,000 men and women between 1988 and 1994. This information was compared with the results from blood tests for uric acid. The researchers found that those who drank four or more coffees a day were more likely to have a much lower uric acid level in the blood, compared with those who drank one or fewer cups. Tea had no measurable effect but decaffeinated coffee did, suggesting that the active ingredient was not caffeine. (C)BBC

Keyword: Drug Abuse
Link ID: 10336 - Posted: 05.26.2007

By Nikhil Swaminathan Without hearing a word, a new study asserts, a four-month-old child can tell when speakers switch to another language, simply by observing changes in facial contortions, such as shapes made by the mouth as well as mannerisms, like the head-bobbing rhythm that varies between different tongues. It has been well documented since the late 1980s that very young children can discriminate between languages when they are spoken, but researchers wanted to determine if they could also recognize changes based on a speaker's gestures. Toward that end, researchers from the University of British Columbia (U.B.C.) in Vancouver separated 36 infants into three separate groups of four-, six- and eight-month-olds. They had the babies sit on their mothers' laps and watch bilingual speakers—all women—on a muted television screen read from a children's book in either English or French. Working first with babies from homes where only English was spoken, researchers began a video with a storyteller who read in one language, then switched to reading in the other tongue when the baby started to lose interest. After the transition, the two youngest sets of infants showed renewed interest, indicating they recognized that something had changed, piquing their curiosity. © 1996-2007 Scientific American, Inc

Keyword: Language; Development of the Brain
Link ID: 10335 - Posted: 06.24.2010

Mohamad Hassoun Artificial neural networks are parallel computational models, comprising densely interconnected adaptive processing units. These networks are composed of many but simple processors (relative, say, to a PC, which generally has a single, powerful processor) acting in parallel to model nonlinear static or dynamic systems, where a complex relationship exists between an input and its corresponding output. A very important feature of these networks is their adaptive nature, in which "learning by example" replaces "programming" in solving problems. Here, "learning" refers to the automatic adjustment of the system's parameters so that the system can generate the correct output for a given input; this adaptation process is reminiscent of the way learning occurs in the brain via changes in the synaptic efficacies of neurons. This feature makes these models very appealing in application domains where one has little or an incomplete understanding of the problem to be solved, but where training data is available. One example would be to teach a neural network to convert printed text to speech. Here, one could pick several articles from a newspaper and generate hundreds of training pairs—an input and its associated, "desired" output sound—as follows: the input to the neural network would be a string of three consecutive letters from a given word in the text. © 1996-2007 Scientific American, Inc.

Keyword: Learning & Memory; Robotics
Link ID: 10334 - Posted: 06.24.2010

By Constance Holden Boys with the longest ring fingers relative to their index fingers tend to excel in math, according to a new study. In girls, shorter ring fingers predict better verbal skills. The link, according to the researchers, is that testosterone levels in the womb influence both finger length and brain development. Scientists have been interested for years in the observation that ratios of finger lengths differ in men and women. In men, the ring (fourth) finger is usually longer than the index (second); their so-called 2D:4D ratio is lower than 1. In females, the two fingers are more likely to be the same length. Because of this sex difference, some scientists believe that a low ratio could be a marker for higher prenatal testosterone levels, although it's not clear how the hormone might influence finger development. The 2D:4D ratio has also been fingered in connection with brain-related characteristics--most often in males--such as depression, left-handedness, musical ability, and homosexuality. In the latest such study, psychologist Mark Brosnan and colleagues at the University of Bath in the United Kingdom photocopied the hands of 74 boys and girls aged 6 and 7. They compared the measurements of the second and fourth fingers with the children's scores on a standard U.K. test of math and literacy. In boys, the lower the ratio, the better their math scores, the team reports in the May issue of the British Journal of Psychology. The boys with the lowest ratios also were the ones whose abilities were most skewed in the direction of math rather than literacy. © 2007 American Association for the Advancement of Science

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 10333 - Posted: 06.24.2010

A popular stereotype that boys are better at mathematics than girls undermines girls' math performance because it causes worrying that erodes the mental resources needed for problem solving, new research at the University of Chicago shows. The scholars found that the worrying undermines women's working memory. Working memory is a short-term memory system involved in the control, regulation and active maintenance of limited information needed immediately to deal with problems at hand. They also showed for the first time that this threat to performance caused by stereotyping can also hinder success in other academic areas because mental abilities do not immediately rebound after being compromised by mathematics anxiety. "This may mean that if a girl takes a verbal portion of a standardized test after taking the mathematics portion, she may not do as well on the verbal portion as she might do if she had not been recently struggling with math-related worries and anxiety," said Sian Beilock, Assistant Professor in Psychology and lead investigator in the study. "Likewise, our work suggests that if a girl has a mathematics class first thing in the morning and experiences math-related worries in this class, these worries may carry implications for her performance in the class she attends next," she added. The results of the study appear in the current issue of the Journal of Experimental Psychology: General.

Keyword: Sexual Behavior; Emotions
Link ID: 10332 - Posted: 05.25.2007

By Christopher Lee In the 43 years since the U.S. surgeon general warned of the dangers of cigarette smoking, the percentage of Americans who light up has been cut in half, tobacco companies have paid billions of dollars in legal settlements and smoking has come to be widely reviled as a nasty habit. But that is not enough -- not when there are 440,000 deaths a year from tobacco use and $89 billion annually in smoking-related health costs, the influential Institute of Medicine said yesterday in a report that called for several new measures to further drive down tobacco use. The institute is a branch of the National Academies, a scientific organization chartered by Congress to advise the government on scientific and technical issues. "There are still 45 million cigarette smokers and another 9.7 million users of other tobacco products," said Richard J. Bonnie, a University of Virginia law professor who led the panel of 14 experts that produced the report. "Most of them regret having taken up the habit and struggle to quit. The nation's goal should be to reduce tobacco use so substantially that it is no longer a significant public health problem." To that end, the report calls for state and local governments to ban smoking in malls, restaurants and virtually all other public indoor settings, and for the Food and Drug Administration to regulate the marketing, packaging and sale of tobacco products. © 2007 The Washington Post Company

Keyword: Drug Abuse
Link ID: 10331 - Posted: 06.24.2010

By John Tierney There’s more encouraging scientific news on the use of marijuana to alleviate pain: a study has shown that effective doses of cannabis can be delivered with vaporizers, which enable patients to get the therapeutic benefits without inhaling harmful smoke. Meanwhile, though, researchers are still struggling against their biggest bureaucratic obstacle, the Drug Enforcement Administration. On Wednesday they made their case at a press conference on the sidewalk outside the headquarters of D.E.A., which still hasn’t followed the recommendation of its own administrative law judge in a medical-marijuana case. In February, as I noted, the judge concluded “that there is currently an inadequate supply of marijuana available for research purposes” and ruled that Lyle Craker, a professor of plant and soil sciences at the University of Massachusetts, should be given permission by the D.E.A. to grow it for researchers. The ruling became final last week, but the D.E.A. still hasn’t acted and refuses to comment on the issue, as the A.P. and the Washington Post report in articles about the press conference. Marc Kaufman of the Post quotes a researcher who joined Dr. Craker on the sidewalk: “The D.E.A. has an opportunity here to live up to its rhetoric, which has been that marijuana advocates should work on conducting research rather than filing lawsuits,” said Richard Doblin, president of the Multidisciplinary Association for Psychedelic Studies, which has fought for years for access to government-controlled supplies to test possible medical uses of marijuana. Copyright 2007 The New York Times Company

Keyword: Drug Abuse; Pain & Touch
Link ID: 10330 - Posted: 06.24.2010

Kerri Smith Even before they begin to speak themselves, a young baby can tell when you're speaking a different language just by looking at your face. Canadian researchers came to these conclusions after studying videos of babies from monolingual and bilingual homes. But unless they are growing up in a bilingual home, babies lose this skill by the time they are eight months old. The study shows the importance of visual cues, such as the shape of the mouth, for babies in the early stages of acquiring language. Babies are good at linking certain bits of information about speech — such as the shape of the mouth and the sound that accompanies it — and can distinguish between mouths making 'ooh' and 'ee' sounds, for example. But this is the first time it's been shown that they can distinguish different languages from visual cues alone. But this ability soon disappears, however, if babies are exposed to only one language home. This came as a surprise to the researchers. "I really expected this ability to progressively get better over the first year of life," says Whitney Weikum of the University of British Columbia in Vancouver, Canada, who led the study. ©2007 Nature Publishing Group

Keyword: Language; Development of the Brain
Link ID: 10329 - Posted: 06.24.2010