By Matt McMillen From the start of their marriage, Jeremy Gaylord had a habit of walking away from his wife, Nancy, while she was in mid-sentence. That annoyed her. But when he also did it to people at parties, she took action. "I'd slam my foot down on his to keep him from drifting off," she recalled, laughing, in a recent phone interview from the couple's home in Bridgewater, Vt. Nancy thought he was just plain rude. Five years ago, she learned there was another possible explanation: attention-deficit hyperactivity disorder, or ADHD. When Jeremy's attention wandered, he did, too. Just about everyone occasionally zones out, procrastinates or speaks and acts without thinking. But for those with ADHD -- including many who don't know they have the disorder -- such experiences are more frequent, intense and disruptive, said Tom Brown, assistant clinical professor of psychiatry at Yale University and author of "Attention Deficit Disorder in Children and Adults" (Yale University Press, 2005). All of which can be hard on a relationship -- especially a committed one. It's not that people with ADHD don't inspire love or affection. "There are likable, lovable sides to ADHD, " said Brown. People with the disorder are often "spontaneous, funny as hell, and bring a fresh view on things to a relationship." It's just that their admirers generally have to balance these traits with a few exasperating ones. © 2006 The Washington Post Company

Keyword: ADHD
Link ID: 8677 - Posted: 06.24.2010

By BENEDICT CAREY The only responsible way to manage schizophrenia, most psychiatrists have long insisted, is to treat its symptoms when they first surface with antipsychotic drugs, which help dissolve hallucinations and quiet imaginary voices. Benedict Carey will answer reader questions about this article. E-mail your questions to askscience@nytimes.com. His answers will be posted at nytimes.com/science on Friday. Delaying treatment, some researchers say, may damage the brain. But a report appearing next month in one of the field's premier journals suggests that when some people first develop psychosis they can function without medication — or with far less than is typically prescribed — as well as they can with the drugs. And the long-term advantage of treating first psychotic episodes with antipsychotics, the report found, was not clear. The analysis, based on a review of six studies carried out from 1959 to 2003, exposes deep divisions in the field that are rarely discussed in public. In the last two decades, psychiatrists have been treating people with antipsychotic drugs earlier and more aggressively than ever before, even testing the medications to prevent psychosis in high-risk adolescents. Copyright 2006 The New York Times Company

Keyword: Schizophrenia
Link ID: 8676 - Posted: 06.24.2010

By Constance Holden Only about two-thirds of depressed people feel better from taking antidepressant medication. Currently, doctors have no way of knowing who is likely to benefit from what drug. But now researchers have identified a gene variant that appears to enhance the odds of benefiting from antidepressants known as selective serotonin reuptake inhibitors (SSRIs). It's "a step on the road to true personalized medicine," says co-author Dennis Charney, psychiatrist at Mount Sinai Medical Center in New York City. The findings could also help explain why blacks appear to respond less than whites to antidepressants, says the lead author, psychiatrist Francis McMahon of the National Institute of Mental Health in Bethesda, Maryland. The beneficial gene variant--for a type of serotonin receptor--is far more common in whites than in blacks. McMahon and colleagues analyzed DNA samples from 1953 patients diagnosed with major depression who were being treated with the SSRI citalopram (Celexa). The patients were part of the largest-ever clinical trial for depression, called STAR*D. To scout out genes that might be associated with treatment response, they looked at 768 markers on 68 candidate genes. SSRIs act on the neurons that send out serotonin, a neurotransmitter that affects many things including mood and circadian rhythms. These antidepressants, which often have fewer side effects than others, prevent transmitting preventing neurons from soaking up unused serotonin, thus giving the serotonin neurotransmitter more time in the synapse to exert an effect. SSRIs also indirectly down-regulate the 2A receptor on postsynaptic (receiving) neurons, which is also necessary for the drugs to work. © 2006 American Association for the Advancement of Science

Keyword: Depression; Genes & Behavior
Link ID: 8675 - Posted: 06.24.2010

Work reported this week provides new evidence that marsupials, like primates, have functional color vision based on three different types of color photoreceptor cones--but unlike primates, a component of marsupial color vision includes sensitivity to ultraviolet wavelengths. In the study, researchers employed behavioral tests to show that at least one type of marsupial uses its detection of UV light as part of its ability to discriminate between colors. The new work is reported by a group including Dr. Catherine Arrese of the University of Western Australia and appears in the March 21st issue of Current Biology. The most prevalent system of color vision in mammals is known as dichromacy, which is a color-detection system based on two types of cone photoreceptors--those sensitive to short (SWS) and medium-to-long (M/LWS) wavelengths. Trichromacy, which is used by humans, was thought to be unique to primates that have re-evolved a third cone type from the duplication of the MWS/LWS gene, which enables the discrimination of green-red colors. But the researchers' previous physiological studies in Australian marsupials provided original evidence for the potential of trichromatic color vision in mammals other than primates. The findings were consistent in several distantly related marsupial species, indicating that the presence of three spectrally distinct cone types, sensitive to short (SWS), medium (MWS), and long (LWS) wavelengths, is a common feature of Australian marsupials. However, since evidence of color vision cannot be derived from physiological studies alone, marsupial trichromacy remained to be established with an unequivocal behavioural approach.

Keyword: Vision
Link ID: 8674 - Posted: 03.21.2006

A research team at Uppsala University, Sweden has shown in a new study, published in the journal Acta Zoologica, that the size of the spot on a male collared flycatcher's forehead reflects how well the immune defence system combats viruses such as avian influenza. The white spot is also attractive to female birds searching for a mate. Evolutionary biologists have long attempted to explain why individuals of a species differ in appearance and why the choice of a mate is influenced by behaviour and appearance features that cannot reasonably be thought to have any usefulness. Therefore, they have begun to look more and more at the genetics behind what are called secondary sexual characters, such as the tail of a peacock, the stripes of the female gulf pipefish, and the white spot on the forehead of the collared flycatcher. In many species both males and females prefer to mate with those who have the largest or most colourful of these ornaments or who have the most complex song, for instance. One theory says that the ornaments are clearest on individuals that are in good health and that both the size and the condition of the ornament are heritable. This leads to the question of why evolution did not select the same appearance and good health for all individuals. Is there something in the environment that is constantly changing and can govern the genetics of appearance and health, leading, instead, to diversity?

Keyword: Sexual Behavior; Evolution
Link ID: 8673 - Posted: 03.21.2006

By Jennifer Viegas, Discovery News — Diving beetles engage in such exhausting, uncomfortable sex that these insects have actually evolved two different types of females, as well as unusual variations among males, according to a new study. The find adds to the growing body of evidence that sexual conflict between males and females influences evolution. In many cases, individuals over time develop characteristics that are appealing to the opposite sex. For diving beetles, however, researchers believe females have tried to avoid the painful sex for so long that some have actually evolved a feature that enables them to spurn most suitors. The result is that the insect family Dytiscidae includes species, such as the diving beetles Dytiscus lapponicus and Graphoderus zonatus verrucifer, which each have two distinct types of females. D. lapponicus has females with smooth and furrowed backs, while G.z. verrucifer has females with smooth and granulated backs. The furrows and granulation allow these types to avoid frequent sex with males, which grab onto the females with suction-cupped feet. Findings are published in the current issue of The American Naturalist. © 2006 Discovery Communications Inc.

Keyword: Sexual Behavior; Evolution
Link ID: 8672 - Posted: 06.24.2010

A version of a gene previously linked to impulsive violence appears to weaken brain circuits that regulate impulses, emotional memory and thinking in humans, researchers at the National Institutes of Health's (NIH) National Institute of Mental Health (NIMH) have found. Brain scans revealed that people with this version – especially males – tended to have relatively smaller emotion-related brain structures, a hyperactive alarm center and under-active impulse control circuitry. The study identifies neural mechanisms by which this gene likely contributes to risk for violent and impulsive behavior through effects on the developing brain. NIMH intramural researchers Andreas Meyer-Lindenberg, M.D., Daniel Weinberger, M.D., Ph.D., and colleagues report on their magnetic resonance imaging (MRI) study online in the Proceedings of the National Academy of Sciences during the week of March 20, 2006. "These new findings illustrate the breathtaking power of 'imaging genomics' to study the brain's workings in a way that helps us to understand the circuitry underlying diversity in human temperament," said NIH Director Elias A. Zerhouni, M.D., who conducted MRI studies earlier in his career. "By itself, this gene is likely to contribute only a small amount of risk in interaction with other genetic and psychosocial influences; it won't make people violent," explained Meyer-Lindenberg. "But by studying its effects in a large sample of normal people, we were able to see how this gene variant biases the brain toward impulsive, aggressive behavior."

Keyword: Aggression; Genes & Behavior
Link ID: 8671 - Posted: 06.24.2010

Roxanne Khamsi Love's arrow may have helped Cupid's match-making, but it was never slathered in mucous. Yet to double their chances of paternity, some male snails fire slimy darts at their would-be female mates. “Snails that hit their partners with a dart are able to father more babies,” explains Ronald Chase of McGill University in Montreal. The so-called love darts are wielded by a number of molluscs, including the brown garden snail (Cantareus aspersus) where it sits on the right side of its body, adjacent to a mucus-producing gland. A male snail passes approximately 5.5 million sperm to its partner in a single mating, Chase says. But he adds that only about 1400 sperm of these millions survive the attacks of enzymes, which digest the sperm within the female. Furthermore, snails mate promiscuously, so one sperm donation does not ensure fatherhood. Chase and colleague Katrina Blanchard set up an experiment to test the idea that pricking a mate with a dart raises a male's chances of siring offspring. This involved 38 female brown garden snails, each paired with two male partners that had each had their darts surgically removed – the darts take a week to grow back. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior
Link ID: 8670 - Posted: 06.24.2010

By Matcheri S. Keshavan, MD It was not too long ago that the management of schizophrenia was generally viewed as pessimistic, and focused primarily on symptom relief. Over the past two decades, there has been a paradigm shift in our approach to the overall management of schizophrenia, toward preventive and early interventions. These approaches are being increasingly guided by recent pathophysiological models. In particular, it has become clear that neurobiological alterations are seen before onset of the illness (the premorbid phase) (Johnstone et al., 2002) and may progress during the early stages of the illness (the prodromal phase). Further deterioration in brain structure and function may appear in some cases after characteristic symptoms of the illness begin (the psychotic phase), especially during the initial years. These observations suggest a critical window of opportunity, early in the illness, to effect lasting modifications in overall illness course (Keshavan et al., 2005a). The three key questions for the field are: Can schizophrenia be prevented in those at risk for the disorder (primary prevention)? Can the first episode of psychosis be prevented in patients experiencing the prodromal phase of the illness (secondary prevention)? Can we prevent relapses and further functional decline in patients who have already experienced the first episode of psychosis (tertiary prevention)? Copyright © 2006 CMP Healthcare Media Group LLC,

Keyword: Schizophrenia
Link ID: 8669 - Posted: 06.24.2010

By Shankar Vedantam When Wayne Kanuch received a diagnosis of Parkinson's disease in 1993, the last thing he imagined was that the drug prescribed to treat his illness would turn him into a compulsive gambler and put his libido into overdrive. Kanuch's marriage ended in divorce, partly as a result of the sexual pressures he placed on his wife, and he began losing fortunes at the racetrack. He was fired from his job at Chevron for trolling for dates on the Internet while at work, and he quickly went bankrupt. "I contemplated suicide a couple of times," he said in an interview last week. "Everyone was blaming me, and I was looking at the mirror and blaming myself and asking why I could not stop." New evidence unearthed by scientists at the Food and Drug Administration, Duke University and other centers suggest the reason Kanuch could not stop is that the drug being used to treat Parkinson's boosted the level of dopamine in his brain. Researchers are looking into the possibility that dopamine, which is associated with a host of addictive behaviors, may turn some Parkinson's patients into obsessive pleasure seekers. © 2006 The Washington Post Company

Keyword: Parkinsons; Drug Abuse
Link ID: 8668 - Posted: 06.24.2010

Ben Harder Ansel Adams once called his photography of the nation's parklands a "blazing poetry of the real." If scientific data were verse, that description would also fit Chad Moore's pictures. Taken in dozens of national parks, mostly in the western United States, Moore's images emphasize contrast, horizon, and sky. But they aren't imitations of Adams' art. In the name of science, Moore photographs the darkness, but his subject may be in peril. Moore's data demonstrate that artificial light from urban areas penetrates deep into some of America's most remote, wild places. For species and ecosystems that have evolved with a nightly quota of darkness, light pollution can be a force of ecological disruption, other research has suggested. With the new images, ecologists can identify geographic areas where sensitive species are most likely to be affected. The inventory of images also provides a reference point for measuring future changes in light pollution, Moore says. Most of this light originates in cities as illumination from buildings and streets. Light reflects off moisture and dust in the air, creating "sky glow," says ecologist Travis Longcore of the Urban Wildlands Group in Los Angeles. In some places, it obscures the starlight. Copyright ©2006 Science Service.

Keyword: Biological Rhythms
Link ID: 8667 - Posted: 06.24.2010

Losing sleep can interfere with the part of the brain responsible for finding your way round, a study says. US researchers found rats that were deprived of sleep had difficulty navigating a maze. Restricting sleep interfered with the rats' spatial memory - responsible for recording information about the surrounding environment, the team said. But UK experts were divided over the findings published in the Journal of Neurophysiology. Spatial memory is essential for rats and humans to remember familiar environments, people use it to find their way round a city, while it is used by rats in hunting for food. The team took two groups of rats, putting one in a water maze where they could not see or smell the exit. The rats were repeatedly put in the maze again once they had slept with some being allowed to sleep for six hours longer than others. Researchers found the rats which had more sleep produced more cells in the hippocampus part of the brain, which is responsible for spatial learning as it is in humans, and were better at finding their way out. The second group were also put in a maze, but were allowed to see and smell the exit - the door was scented with citrus - which was moved every fourth trial. In this group, the sleep deprived rats performed better. The researchers said this was unexpected and suggested the sleep deprived rats were quicker to use their senses because their spatial learning was impaired. (C)BBC

Keyword: Sleep; Learning & Memory
Link ID: 8666 - Posted: 03.18.2006

Chickadees are those tiny birds that sing their own name, but researchers say they are not looking for attention, they're picking a fight. University of Washington biologist Chris Templeton says if you ever hear a chickadee scream "chick-a-dee-dee-dee-dee," you ought to take cover, because them's fightin' words! "We've seen chickadees take on cats, we've seen chickadees take on owls, and we've seen chickadees take on eagles," he says. As reported in Discover magazine, Templeton set up an outdoor aviary in Montana where he kept flocks of chickadees. He collected sound recording of the chickadees in order to learn more about what their 16 different calls mean. "Not only do they have all these different types of calls but the way that they say each call may have different meanings," Templeton explains. The way chickadees sing their notorious chick-a-dee-dee call is an expression of how they feel about predators. When Templeton tethered owls, hawks, and eagles, as well as a cat and a ferret to pedestals inside the aviary he discovered that the chickadees use the "dee" in their song to call their flock mates to action and to tell them how dangerous a nearby predatory may be. The more dees in their call, the bigger the danger. © ScienCentral, 2000-2006.

Keyword: Sexual Behavior; Animal Communication
Link ID: 8665 - Posted: 06.24.2010

Electrical impulses foster myelination, the insulation process that speeds communication among brain cells, report researchers at two institutes of the National Institutes of Health. “This finding provides important information that may lead to a greater understanding of disorders such as multiple sclerosis that affect myelin, as well as a greater understanding of the learning process,” said Duane Alexander, M.D., Director of the NICHD. The study appears in the March 16 Neuron and was conducted by researchers at the National Institute of Child Health and Human Development and the National Cancer Institute. Neurons — specialized cells of the brain and nervous system — communicate via a relay system of electrical impulses and specialized molecules called neurotransmitters, explained the study’s senior author, R. Douglas Fields, Ph.D., Head of NICHD’s Nervous System Development and Plasticity Section. A neuron generates an electrical impulse, causing the cell to release its neurotransmitters, he said. The neurotransmitters, in turn, bind to nearby neurons. The recipient neurons then generate their own electrical impulses and release their own neurotransmitters, triggering the process in still more neurons, and so on. Neurons conduct electrical impulses more efficiently if they are covered with an insulating material known as myelin, Dr. Fields added. Layers of myelin are wrapped around the fiber-like projections of neurons like electrical tape wrapped spiral-fashion around an electrical cable. Human beings are born with comparatively little myelin, and neurons become coated with the material as they develop. Moreover, mental activity appears to influence myelination, Dr Fields said. For example, neglected children have less myelin in certain brain regions than do other children.

Keyword: Glia; Multiple Sclerosis
Link ID: 8664 - Posted: 06.24.2010

A rare opportunity to study patients with an intractable form of epilepsy has led to the identification of specific neurons in the human brain that respond to novel or familiar objects. The discovery was made using micro-thin electrodes that read electrical activity from single neurons inside the brains of patients who were undergoing treatment to determine the origin of their epileptic seizures. The research by Howard Hughes Medical Institute scientists and their colleagues may help researchers understand how the human brain distinguishes new objects from more familiar objects, a skill crucial to survival. The research group, which was led by Howard Hughes Medical Institute investigator Erin Schuman at the California Institute of Technology, reported their findings in the March 16, 2006, issue of the journal Neuron. First author Ueli Rutishauser of Caltech and co-author Adam Mamelak of Huntington Memorial Hospital and Cedars-Sinai Medical Center collaborated on the studies with Schuman. Prior to these studies, researchers had only identified regions of the human brain involved in detecting novel images or objects using functional magnetic resonance imaging. Those studies yielded conflicting evidence about whether such neurons existed in the learning centers of the brain - the hippocampus and amygdala. The hippocampus is involved in learning and memory, and the amygdala helps to etch memories that are associated with emotions such as fear. © 2006 Howard Hughes Medical Institute.

Keyword: Vision; Epilepsy
Link ID: 8663 - Posted: 06.24.2010

Vulnerability to both alcohol and nicotine abuse may be influenced by the same genetic factor, according to a recent study supported by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health (NIH). In the study, two genetically distinct kinds of rat – one an innately heavy-drinking strain bred to prefer alcohol ("P" rats), the other strain bred to not prefer alcohol ("NP" rats) -- learned to give themselves nicotine injections by pressing a lever. Researchers found that P rats took more than twice as much nicotine as NP rats. Their findings were reported recently in the Journal of Neuroscience. "Our findings suggest that the genetic factor underlying the high alcohol consumption seen in P rats may also contribute to their affinity for nicotine," said lead author A.D. Lê, Ph.D., a NIAAA-supported researcher at Toronto's Centre for Addiction and Mental Health and University of Toronto. Researchers have known for some time that people who smoke are more likely to drink alcohol than non-smokers. Similarly, smoking is three times more common in people with alcoholism than in the general population. Since previous studies have also determined that genetics plays an important role in both alcohol and nicotine addictions, researchers have hypothesized that the same gene or genes may influence the co-abuse of these substances.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 8662 - Posted: 06.24.2010

By GARDINER HARRIS An unusual number of deaths among patients in a large study of Aricept, the most popular drug to treat Alzheimer's disease, is raising concern among federal drug officials and some disease experts. In the study, of 974 patients who suffered from dementia related to heart disease, 11 deaths occurred among the patients taking Aricept, while no deaths occurred among those taking dummy pills. The Food and Drug Administration is examining the results of the study, said Susan Bro, an agency spokeswoman. The agency undertook a quick review of earlier Aricept studies and found no cause for concern, Ms. Bro said. "The drug remains a safe option for patients who are receiving it," she said. But experts in Alzheimer's disease said that the new study should not be dismissed and that it might indicate that Aricept and similar drugs increased the risks of heart disease. Because Aricept's benefits in fighting Alzheimer's disease are at best mild, any increase in risk should cause concern, they said. "These drugs are well known to slow the heart and constrict the respiratory passage ways," said Dr. Lon Schneider, a professor of psychiatry, neurology and gerontology at the University of Southern California. Copyright 2006 The New York Times Company

Keyword: Alzheimers
Link ID: 8661 - Posted: 03.17.2006

Botulinum neurotoxin A can be either the greatest wrinkle remover or one of the world's most potent biological weapons. To perform either job, however, the toxin must first find a way to enter cells. But understanding how the toxin — one of seven neurotoxins produced by the bacterium Clostridium botulinum — enters nerve cells has proved elusive for scientists. Despite a decade-long search for the receptor by labs around the world, researchers had come up empty handed. Now, a research team led by Howard Hughes Medical Institute (HHMI) researcher Edwin R. Chapman reports that it has identified the cellular receptor for botulinum neurotoxin A. The group's work was published in the March 16, 2006, edition of ScienceXpress, which provides electronic publication of selected Science papers in advance of print. The finding offers important new insights that suggest how the toxin shuts down nerve cells with deadly efficiency. In the clinic, the toxin, which is also known as botox, is used to treat forehead wrinkles, migraine headaches, urinary retention, eye muscle disorders, and excessive sweating. The same toxin also has more nefarious uses, and is considered a potential bioterror threat because it can kill people by paralyzing motor nerves in diaphragm muscles, causing breathing to stop. Lack of knowledge about the identity of the cell surface receptor that botulism toxin A uses to invade nerve cells has hindered the development of new antidotes to the toxin. © 2006 Howard Hughes Medical Institute.

Keyword: Neurotoxins
Link ID: 8660 - Posted: 06.24.2010

Commentary by Jennifer Granick If we can put a man on the moon, why can't we detect when someone is lying? Just as the space program seemed to be just the thing for combating communism during the Cold War, lie detection looks like just what we need in the fight against terrorism. The popular press, including Wired magazine, has been pretty optimistic that a high-tech replacement for the archaic and mistrusted polygraph machine is coming soon. Last weekend, Stanford Law School hosted a workshop called "Reading Minds: Lie Detection, Neuroscience, Law and Society," where attendees took a closer look at the technology -- a look that suggests we're still light years away. As a criminal defense attorney, I found the polygraph test useful, and I submitted my clients to testing on several occasions. There's little evidence that the polygraph is accurate, and most courts won't admit test results as evidence. But many people in law enforcement, including the FBI, believe in lie detectors, so strapping a defendant to a polygraph can be a useful tool in convincing prosecutors to drop borderline charges. One time, I got to sit in the room as the examiner, paid by our firm, strapped and clipped the sensors to our high-strung, jittery female client. The machine looked like something out of the 1950s, with wires and electrodes connected to needles that marked variations on a roll of paper. The test measures the subject's changes in respiration, heartbeat and perspiration -- anxiety reactions allegedly correlated with lying. © Copyright 2006, Lycos, Inc.

Keyword: Stress
Link ID: 8659 - Posted: 06.24.2010

Even for scientists, it's not every day you see a hairless mouse glowing bright green under a fluorescent light. And for scientists searching for stem cells that could grow into nerve or brain cells, seeing such a mouse meant finding a possible whole new source of such cells. The scientists had given the mouse a gene so that areas would glow green where such stem cells might be found. They expected part of the mouse around the head to glow green. Instead, the entire mouse was aglow. "I'll never forget the minute that we made that observation," says Robert Hoffman, president of AntiCancer, Inc., where the finding took place. Because of that moment, which Hoffman says was, in fact, a "lucky discovery," company scientists have been working on what could be a new source of adult stem cells. Their most recent research, published in Proceedings of the National Academy of Sciences (PNAS), shows that they've been able to use stem cells taken from a mouse hair follicle to help regenerate damaged nerves in mice. In previous research, also published in PNAS, they showed the stem cells could become special brain cells called neurons. © ScienCentral, 2000-2006.

Keyword: Stem Cells
Link ID: 8658 - Posted: 06.24.2010