By Shankar Vedantam Widely used antidepressants double the risk of suicidal behavior in young adults, from around three cases per thousand to seven cases per thousand, according to a huge federal analysis of hundreds of clinical trials. It marks the first time regulators have acknowledged that the drugs can trigger suicidal behavior among patients older than 18. Officials at the Food and Drug Administration said yesterday that the higher risk was found in patients 18 to 25 and that the risk faded among older patients. The finding comes two years after the agency ordered a "black box" warning on the drug labels following the discovery of a heightened risk of suicidal behavior among children taking the pills. After reviewing the latest data, an expert federal panel yesterday recommended that agency officials tell doctors and the public of the risk but also find a way to note that the risk declines with age, and that leaving depression untreated is also risky. While the studies on the relationship between the drugs and suicide appear contradictory, the experts said one possibility is that the drugs may pose a risk early in treatment but have a protective effect in the long term. The agency is leaning toward expanding its black box warning, said Thomas Laughren, director of FDA's division of psychiatric drug products. Officials said they will try to write language that would urge clinicians to use the drugs carefully, not abandon them. © 2006 The Washington Post Company

Keyword: Depression
Link ID: 9748 - Posted: 06.24.2010

Two Howard Hughes Medical Institute research teams working independently have discovered new information about how the botulinum neurotoxin shuts down neurons with deadly efficiency. By providing detailed views of the toxin plugged into its neuronal receptor, the new studies could aid efforts to engineer specialized versions of the powerful neurotoxin that is used to treat a wide array of medical problems. The two groups were led by HHMI investigators Axel Brunger at Stanford University and Edwin Chapman at the University of Wisconsin at Madison. They published their findings December 13, 2006, in advance online publications in the journal Nature. "Botulinum neurotoxins are powerful tools for biologists and find widespread use as therapeutics for the treatment of certain nervous-system diseases," wrote Giampietro Schiavo of the London Research Institute in an accompanying News & Views commentary in Nature. "For these reasons, the papers reported here are of tremendous value." Botulinum neurotoxins are among the most deadly natural toxins in the world. They act by first attaching themselves to receptors on the surface of neurons. The toxins then insinuate an enzyme into the neuron that degrades key proteins required for neurons to communicate with one another. The toxins principally affect muscle-controlling motor neurons activated by the neurotransmitter acetylcholine. They kill by paralyzing the respiratory muscles. There are seven structurally and functionally related botulinum neurotoxins (BoNTs), called serotypes A through G, with each acting in a slightly different manner.

Keyword: Neurotoxins
Link ID: 9747 - Posted: 12.14.2006

The dyslexic brain struggles to read because even small distractions can throw it off, according to a new model of dyslexia emerging from a group of recent studies. The studies contradict an influential, 30-year-old theory that blamed dyslexia on a neural deficit in processing the fast sounds of language. Instead, the studies suggest that children with dyslexia have bad filters for irrelevant data. As a result, they struggle to form solid mental categories for identifying letters and word sounds. Such children may benefit from intensive training under "noisy" conditions to strengthen their mental templates, said University of Southern California neuroscientist Zhong-Lin Lu. Lu was a co-author on three studies, along with lead author and former USC graduate student Anne Sperling (now at the National Institute of Mental Health), USC psychologist Franklin Manis and University of Wisconsin, Madison psychologist Mark Seidenberg. The most recent study is due to be published later this month in Psychological Science. Confusion about dyslexia rivals the confusion of dyslexia. Many still think that to have dyslexia means to mix up your letters (one of many possible symptoms having to do with word recognition, directional ability and decoding of symbols).

Keyword: Dyslexia
Link ID: 9746 - Posted: 12.14.2006

Jennifer Viegas, Discovery News — The color of a dog's fur may seem to be just a whim of nature and genetics that reveals little about the dog. But a new study claims that coat color for at least one breed, the English cocker spaniel, reflects a pooch's personality. Prior research has suggested that fur color is also linked to behavior in labrador retrievers, while the type of fur — in this case, wiry or long — may indicate temperament in miniature dachshunds. Wiry-haired mini dachshunds are often more feisty than their mellower, long-haired cousins. The latest study, recently published in Applied Animal Behavior Science, determined that golden/red English cocker spaniels exhibit the most dominant and aggressive behavior. Black dogs in this breed were found to be the second most aggressive, while particolor (white with patches of color) were discovered to be more mild-mannered. In labrador retrievers, the color rank from most to least aggressive was determined to be yellow, black and chocolate. The behavior-fur color connection is likely due to related genetic coding that takes place during the pup's earliest life stages, according to lead author Joaquín Pérez-Guisado. © 2006 Discovery Communications Inc.

Keyword: Aggression; Genes & Behavior
Link ID: 9745 - Posted: 06.24.2010

Michael Hopkin Imagine being unable to feel any pain at all. For a tiny handful of people, that is the reality — and medical researchers have now pinpointed the mutation that removes their ability to perceive painful sensations. The study began when doctors in northern Pakistan examined a remarkable group of related families in which several individuals seem entirely unaffected by pain. Their attention was first attracted by one member of the clan, a locally famous boy who performed street theatre involving walking on burning coals and stabbing his arms with knives. Although it sounds like a party trick, the condition is devastating, as sufferers don't learn to know their limits. The street-performing boy killed himself on his fourteenth birthday after jumping off a house roof. The researchers studied six of his relatives, aged between 4 and 14 years. All had suffered many cuts and bruises, and injuries to lips and tongue caused by biting themselves; several had fractured bones without noticing. This shows the importance of pain for our health and survival, notes Geoffrey Woods of the Cambridge Institute for Medical Research, UK, who led the study. "Pain is there for a jolly good reason — it stops up damaging ourselves," he says. For example, the pain from a broken arm or sprained ankle encourages us to rest that body part while it recovers. ©2006 Nature Publishing Group

Keyword: Pain & Touch
Link ID: 9744 - Posted: 06.24.2010

By BENEDICT CAREY Public health officials, psychiatrists, grieving parents and outraged former patients will fill a hotel ballroom in Silver Spring, Md., this morning to argue the most bitterly divisive question in psychiatry: do the drugs that doctors prescribe to relieve depression make some people more likely to attempt suicide? The hearing, called by the Food and Drug Administration, will be the first time a government panel has addressed the question since 2004, when impassioned testimony resulted in the agency requiring antidepressant drugs to carry strong warnings that they could increase suicidal thinking or behavior in some children and adolescents. Today’s hearing is expected to be even more contentious. The panel will hear testimony on whether to recommend that the F.D.A. require labels carrying similar warnings for adult patients. The meeting marks the latest chapter in a controversy that began in the late 1980s, soon after Prozac was introduced as the first in a new generation of antidepressants. Over the last 15 years, the debate has come to transcend questions about side effects and labeling. It is now a clash of cultures. Psychiatrists say the debate has scared patients and their families away from the very medications that could save their lives. Critics say psychiatry relies too much on drugs that pose a danger to public health, and too much on drug company money. Copyright 2006 The New York Times Company

Keyword: Depression
Link ID: 9743 - Posted: 06.24.2010

NEW YORK (Reuters Health) - Among people suffering from chronic cough, more than half have symptoms of depression, new research shows. The good news is that the depression seems to lift as the cough improves. Cough is the most common reason people in the US seek medical attention, and several reports have shown that chronic cough can have a significant impact on quality of life, according to Dr. Peter V. Dicpinigaitis, from the Montefiore Medical Center in the Bronx, New York, and colleagues. The team used a standard depression scale called CES-D, in which scores of 16 or greater indicate significant depressive symptoms, to evaluate100 patients who were seen at an academic medical center because of chronic cough. Reporting in the medical journal Chest, the researchers found that 53 percent of the subjects had significant depressive symptoms and the average CES-D score was 18.3. The CES-D was administered again after three months, and results showed that the average score had dropped to 7.4, which coincided with a significant improvement in the average subjective cough score. Further analysis confirmed a significant correlation between the cough and depression scores. © 1996-2006 Scientific American, Inc.

Keyword: Depression
Link ID: 9742 - Posted: 06.24.2010

By Gisela Telis Three neuroscientists have news for Freud-bashers everywhere: hysteria may not be imaginary after all. A study in this week's issue of Neurology adds to a growing body of evidence that real cerebral dysfunction lies behind the mythic malady--and that distractions may offer a way around it. Hysteria involves symptoms ranging from paralysis to seizures that doctors can't trace to an underlying medical problem. Because its sufferers have typically been women, the disease was once dismissed as fakery and even witchcraft. To escape its charged history, the American Psychiatric Association in 1980 began using the term "sensory conversion disorder," after Freud's theory that hysterical patients convert their mental distress into physical suffering. With the advent of new imaging technologies, however, researchers started to conduct novel studies on the subject, scanning the brains of hysterical patients in search of a brain-based cause for the disorder--with conflicting results. Studies that involved stimulating either the afflicted or the unafflicted appendage turned up evidence of cerebral dysfunction. But studies that stimulated both appendages at once found no such evidence, and concluded that there was no brain basis for hysterical symptoms. In hopes of making sense of these conflicting findings, neuropsychiatrist Omar Ghaffar and his colleagues at the Sunnybrook Health Sciences Centre in Toronto, Canada, decided to repeat these experiments--this time using advanced functional magnetic resonance imaging (fMRI). The researchers recruited three women with sensory conversion disorder and used vibrations to stimulate both numb and feeling body parts. As in the previous experiments, the women had no cerebral response when only the numb appendage was stimulated, but they did show an fMRI response in the appropriate brain region when the numb appendage was stimulated in tandem with a feeling appendage. © 2006 American Association for the Advancement of Science.

Keyword: Stress
Link ID: 9741 - Posted: 06.24.2010

It’s been shown that the left side of the brain processes language and the right side processes music; but what about a language like Mandarin Chinese, which is musical in nature with wide tonal ranges? UC Irvine researcher Fan-Gang Zeng and Chinese colleagues studied brain scans of subjects as they listened to spoken Mandarin. They found that the brain processes the music, or pitch, of the words first in the right hemisphere before the left side of the brain processes the semantics, or meaning, of the information. The results show that language processing is more complex than previously thought, and it gives clues to why people who use auditory prosthetic devices have difficulty understanding Mandarin. The study appears in this week’s online early edition of the Proceedings of the National Academy of Sciences. In the English language, Zeng says, changes in pitch dictate the difference between a spoken statement and question, or in mood, but the meaning of the words does not change. This is different in Mandarin, in which changes in pitch affect the meaning of words. “Most cochlear implant devices lack the ability to register large tonal ranges, which is why these device users have difficulty enjoying music … or understanding a tonal language,” says Zeng, a professor of otolaryngology, biomedical engineering, cognitive sciences, and anatomy and neurobiology. © Copyright 2002-2006 UC Regents

Keyword: Language; Laterality
Link ID: 9740 - Posted: 06.24.2010

Lauran Neergaard, Associated Press — Scientists appear to have found a fingerprint of Alzheimer's disease lurking in patients' spinal fluid, a step toward a long-awaited test for the memory-robbing disease that today can be diagnosed definitively only at autopsy. Researchers at New York's Weill Cornell Medical College discovered a pattern of 23 proteins floating in spinal fluid that, in very preliminary testing, seems to identify Alzheimer's — not perfectly, but with pretty good accuracy. Far more research is needed before doctors could try spinal-tap tests in people worried they have Alzheimer's, specialists caution. But the scientists already are preparing for larger studies to see if this potential "biomarker" of Alzheimer's, reported Tuesday in the journal Annals of Neurology, holds up. "We're looking to an era in which the kinds of uncertainties that many patients and their families face about the diagnosis of Alzheimer's disease will no longer be a problem," predicts Dr. Norman Relkin, a neurologist and the study's senior researcher. About 4.5 million Americans have Alzheimer's, a toll expected to more than triple by 2050 as the population grays. The creeping brain disease gradually robs sufferers of their memories and ability to care for themselves, eventually killing them. There is no known cure; today's drugs only temporarily alleviate symptoms. © 2006 Discovery Communications Inc.

Keyword: Alzheimers
Link ID: 9739 - Posted: 06.24.2010

Ned Stafford Laughter is indeed infectious, according to a new study. Researchers have shown that the mere sound of giggles tickles the same area of the listener's brain that is activated when smiling. The brain's response helps to prepare the facial muscles for a good hearty laugh. "It really seems to be true: 'Laugh and the whole world laughs with you'," says study co-author Sophie Scott, a neuroscientist at University College London in the United Kingdom. The team of played pleasant sounds, such as laughter or cheering, and unpleasant sounds, such as screaming or retching, to volunteers. They then monitored their brains with functional magnetic resonance imaging (MRI). All the sounds triggered neural responses in the premotor cortex of the brain — an area known to prepare groups of facial muscles to respond accordingly. When a person in the study actually smiled or laughed, the neural activity moved to a primary motor cortical region. The neural response in the premotor cortex was, on average, twice as big for pleasant sounds than for unpleasant sounds, the team reports. Since the pleasant sounds have a bigger impact on the bit of the brain that activates muscles to respond in kind, the findings suggests that pleasant sounds are more 'contagious' than unpleasant ones. The research is published this week in the Journal of Neuroscience1. ©2006 Nature Publishing Group

Keyword: Emotions
Link ID: 9738 - Posted: 06.24.2010

Roxanne Khamsi Bats can locate their prey using echolocation without confusion even when immersed in a thick swarm of many hundreds of other bats, and now researchers have discovered the secret. The winged mammals raise the pitch of their echolocation calls to make them stand out against "jamming signals". The finding helps explain how hundreds of bats can hunt in the same area without getting confused by others' calls, and could perhaps inform the design of better radar systems for aircraft. Bats use the echo pattern of their voice to locate insects and other prey – so confusing echoes can cost them dinner. A new study reveals that the flying mammals use a wide range of pitches and simply raise the pitch of their echolocation calls to stand out against other bat calls at the same frequency. Erin Gillam of the University of Tennessee in Knoxville, US, and colleagues conducted experiments on Brazilian free-tailed bats (Tadarida brasiliensis) in the wild. The team positioned itself at a site near a bat cave where the animals typically forage one at a time. When a bat came to the site, scientists recorded its sounds while simultaneously playing pre-recorded echolocation calls at various pitches through a portable speaker. © Copyright Reed Business Information Ltd

Keyword: Hearing
Link ID: 9737 - Posted: 06.24.2010

By Arran Frood "Doc, I am ready to play ball." It had been years since Jeff (not his real name) had touched a basketball. Living with obsessive-compulsive disorder (OCD), Jeff feared contamination from dirt and germs which prevented any part of his body from touching the ground, save for the soles of his shoes. But whilst taking part in a small clinical study to investigate the effects of psilocybin, the hallucinogenic compound found in 'magic' mushrooms, on people with OCD, Jeff's bare feet lay on the floor and he expressed a willingness to engage in an activity, playing with a ball, that just hours before he would have been considered abhorrent. Although Jeff's symptoms gradually returned, other patients also experienced transient relief from their OCD symptoms and one entered an extended period of remission lasting more than six months. Lead researcher Dr Francis Moreno, associate professor of psychiatry at the University of Arizona, Tucson, said: "I really think that participating in the study influenced the patient's remission." It was the first to investigate the therapeutic benefits of psilocybin to be published for more than 30 years. But critics say the study's flawed methodology means that conclusions cannot be made about the drug's efficacy against OCD, and some question whether it should have taken place at all. Professor Jeremy Schwartz, of the University of California, Los Angeles, said: "This study is going to receive a lot of attention and it will create a desire on behalf of a patient population that is suffering and hoping for a 'magic bullet'." (C)BBC

Keyword: OCD - Obsessive Compulsive Disorder; Drug Abuse
Link ID: 9736 - Posted: 12.12.2006

By DAN HURLEY After years of colicky debate over which method is best for getting babies to fall asleep by themselves, experts have a soothing new message: just about all the techniques work, so pick one you are comfortable with and stick with it. Despite their apparent differences, most of the behavioral approaches reviewed in the October issue of the journal SLEEP were supported by evidence that they resulted in infants and toddlers learning to fall asleep independently at bedtime and when they woke during the night. Of the 52 studies examined in the review, 49 showed positive results, with 82 percent of the infants and young children in the studies benefiting significantly. “The key to this whole thing is parents being consistent,” said the senior author of the review, Dr. Jodi A. Mindell, a psychology professor at Saint Joseph’s University in Philadelphia and chairwoman of the task force organized by the American Academy of Sleep Medicine to assess the techniques. She added, “They need to pick a plan they can absolutely follow through on.” Even Dr. Richard Ferber of Children’s Hospital Boston — so strongly linked in the popular imagination with the so-called cry-it-out method that it has come to be known as “Ferberizing” — agreed in an interview that no single approach worked for all children. Copyright 2006 The New York Times Company

Keyword: Sleep
Link ID: 9735 - Posted: 06.24.2010

By BENEDICT CAREY Some graduate students grind out their dissertations in late-night sessions, alone with their thoughts in the wasted fluorescent glow of a windowless lab. Others spend those same hours drinking in bars, “discussing” their thesis over a round or drinks or three. Leonard Lee, a recent graduate of the Massachusetts Institute of Technology, managed to do both at the same time. A few times a week for about six months, Mr. Lee spent his evenings at an on-campus watering hole, either the Thirsty Ear or the Muddy Charles, buying fellow patrons beer, as part of a study of taste. In an interview Dr. Lee, now an instructor at the Columbia University business school, swore that this exercise was not a ruse to meet women or an effort to stick M.I.T with his bar tab. And he has a published paper to back him up: “The Influence of Expectation, Consumption and Revelation on Preferences for Beer,” appearing in the December issue of Psychological Sciences, one of the field’s leading research journals. In the study, Dr. Lee and two M.I.T. researchers, Shane Fredrick and Dan Ariely, found that they could change beer drinkers’ taste preferences by telling them about a secret ingredient in a beer before they drank it. Copyright 2006 The New York Times Company

Keyword: Chemical Senses (Smell & Taste)
Link ID: 9734 - Posted: 06.24.2010

By INGFEI CHEN Thirty years ago, Nick Patterson worked in the secret halls of the Government Communications Headquarters, the code-breaking British agency that unscrambles intercepted messages and encrypts clandestine communications. He applied his brain to “the hardest problems the British had,” said Dr. Patterson, a mathematician. Today, at 59, he is tackling perhaps the toughest code of all — the human genome. Five years ago, Dr. Patterson joined the Broad Institute, a joint research center of Harvard and the Massachusetts Institute of Technology. His dexterity with numbers has already helped uncover startling information about ancient human origins. In a study released in May, scientists at the Broad Institute scanned 20 million “letters” of genetic sequence from each of the human, chimpanzee, gorilla and macaque monkey genomes. Based on DNA differences, the researchers speculated that millions of years after an initial evolutionary split between human ancestors and chimp ancestors, the two lineages might have interbred again before diverging for good. The controversial theory was built on the strength of rigorous statistical and mathematical modeling calculations on computers running complex algorithms. That is where Dr. Patterson contributed, working with the study’s leader, David Reich, who is a population geneticist, and others. Their findings were published in Nature. Copyright 2006 The New York Times Company

Keyword: Evolution; Genes & Behavior
Link ID: 9733 - Posted: 06.24.2010

By JANE E. BRODY Until two months ago, Todd McGee, 34, was a healthy man in top physical condition — a builder, surfer and devoted father of a 15-month-old. The last person anyone would expect to have a stroke. Yet a stroke has left him nearly unable to speak, with months, maybe years, of therapy ahead. Partly because of his age and partly because of the lack of a hospital with an M.R.I. machine where he lives, no one recognized the symptoms of a stroke until it was too late to administer a treatment that could have limited the damage and speeded his recovery. This treatment, with a drug called t-PA (for tissue plasminogen activator), can help dissolve a brain-damaging clot in the 80 percent of victims who have strokes caused by them. But it must be administered within three hours of a stroke to be effective, and the sooner the better. About only one stroke victim in five who could benefit from t-PA receives it, primarily because people don’t realize a stroke is happening and wait too long to get to the hospital. Knowing who is at risk of a stroke, recognizing the symptoms and getting prompt medical help can make a great difference in whether those afflicted live or die and, if they live, how severe the consequences will be. Although about 90 percent of strokes occur in people over 55, they affect young adults, children and even babies. Copyright 2006 The New York Times Company

Keyword: Stroke
Link ID: 9732 - Posted: 06.24.2010

Although biologists are still far from answering this question, scattered evidence for a possible gene influencing sexual orientation has recently encouraged scientists to map out a guide to future research. Because many possibilities for such a gene exist, scientists Sergey Gavrilets and William Rice have recently developed some theoretical guidelines and testable predictions for explaining the evolutionary causes of homosexuality. “During the 1990s there was a short surge of interest by a small number of labs in finding major genes that might mediate homosexuality,” Rice told PhysOrg.com. “However, for a variety of reasons, this effort waned by the turn of the century. I think that—when studying humans—many people shy away from studying sexual phenotypes in general and homosexuality in particular. Much of Sergey's and my motivation in writing our paper was to rekindle an interest in studying the genetic basis of homosexuality. I personally think that if a firm genetic foundation for homosexuality in humans were established, then many people would view this fascinating human phenotype more objectively.” During the past several decades, scientists have discovered some interesting patterns that may point toward genetic causes of homosexuality. Among the findings is that male homosexuality appears to be inherited more often from the mother than the father (Pillard). Also, natural selection might maintain a gene that may decrease the fecundity of one sex because the same gene also increases the fecundity of the other sex. In fact, recent data shows that female maternal relatives of gay men have higher than average reproduction capacity (Camperio-Ciani). © PhysOrg.com 2003-2006

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 9731 - Posted: 06.24.2010

Don Babwin, Associated Press — Squirrels hit the genetic lottery with their chubby cheeks and bushy tails. It's hard to imagine picnickers tossing peanuts and cookies at the rodents if they looked like rats. But good looks alone don't get you through Chicago winters. Nor do they help negotiate a treacherous landscape of hungry cats, cars and metal traps. So how do they do it? And why do they search, huddle, dart, and sometimes forget where they hid their nuts? Joel Brown aims to find out. "We're trying to get a glimpse of what your life is like if you are a city squirrel," said Brown, a biologist at the University of Illinois-Chicago. He and a team of students will trap squirrels in Chicago and its suburbs this winter, taking skin samples for DNA analysis. They'll strap collars on them and watch what they do. And they'll attach threads to acorns and hazelnuts, then see where the squirrels take them and when they eat them. While the methods aren't unlike those used to study animals in exotic lands, little attention has been paid to those in human neighborhoods. It is, after all, a lot sexier to track gorillas in Africa than a squirrel on Main Street. © 2006 Discovery Communications Inc.

Keyword: Intelligence; Learning & Memory
Link ID: 9730 - Posted: 06.24.2010

Jennifer Viegas, Discovery News — Not a morning person? Take solace — new research suggests that "night owls" are more likely to be creative thinkers. Scientists can't yet fully explain why evening types appear to be more creative, but they suggest it could be an adaptation to living outside of the norm. "Being in a situation which diverges from conventional habit — nocturnal types often experience this situation — may encourage the development of a non-conventional spirit and of the ability to find alternative and original solutions," lead author Marina Giampietro and colleague G.M. Cavallera wrote in a study to be published in the February 2007 issue of Personality and Individual Differences. The researchers, who are both in the Department of Psychology at the Catholic University of the Sacred Heart in Milan, Italy, studied 120 men and women of varying ages. A self-report questionnaire evaluated degrees of morning and evening dispositions. In fact, true morning and evening-oriented people are actually rare, since most of us fall somewhere in between. Once the subjects were categorized into either morning, evening or intermediate types, they underwent three tests designed to measure creative thinking. © 2006 Discovery Communications Inc.

Keyword: Biological Rhythms
Link ID: 9729 - Posted: 06.24.2010