By DONALD G. McNEIL Jr. It is the "hey there, big boy" version of the nature-nurture debate: are some gentlewomen born preferring blonds, or do their tastes develop as they age? Idle though the question may sound, it has now been addressed scientifically, though not at the evolutionary level of ladies and gentlemen. Rather, Dr. Eileen A. Hebets of Cornell University chose wolf spiders, and she is not shy about drawing parallels between the instincts of female spiders and female humans. Copyright 2003 The New York Times Company

Keyword: Sexual Behavior; Learning & Memory
Link ID: 4483 - Posted: 11.04.2003

By LINDA CARROLL Thirty years ago, scientists linked prenatal alcohol exposure with a perplexing pattern of birth defects including neurological problems, low birth weight, mental retardation and a set of facial malformations. Up to that time, many doctors had assumed that alcohol was so harmless that it was sometimes administered intravenously to women who were thought to be at risk of losing their pregnancies. But in recent decades, scientists have discovered that alcohol can be remarkably toxic — more than any other abused drug — to developing fetuses. New research with imaging techniques is helping experts uncover which parts of the developing brain are damaged by alcohol exposure. Copyright 2003 The New York Times Company

Keyword: Drug Abuse; Development of the Brain
Link ID: 4482 - Posted: 06.24.2010

The discovery of a gene believed to be connected to morbid obesity has international origins and began as an exploration into the causes of Type I diabetes. The discovery, which will be published in an upcoming issue of the journal Public Library of Science (http://www.plos.org), involves researchers originally from Sweden and France who collaborated at the University of Washington in Seattle. The gene, on Chromosome 10, was first connected to diabetes in 1991 by Dr. Åke Lernmark, R. H. Williams Professor of Medicine and adjunct professor of immunology at the UW. The GAD2 gene is responsible for the protein GAD65, which plays a role in the healthy use of insulin by the body. Lernmark is a native of Sweden, which has one of the highest rates of Type I diabetes incidence in the world.

Keyword: Obesity
Link ID: 4481 - Posted: 11.04.2003

DURHAM, N.C. -- The genes that influence the risk of developing Alzheimer's disease may vary over the course of an individual's lifetime, a new study by Duke University Medical Center researchers finds. The team's results revealed two chromosomal regions not previously known to influence Alzheimer's disease: one linked to the disorder in families that first show symptoms early in life and another in families with very late onset of the disorder's symptoms. While earlier studies have identified genes that underlie early- versus late-onset Alzheimer's disease, the new study is the first to indicate that distinct genes might also determine the very late onset of Alzheimer's disease, in which symptoms first appear after the age of 80, said Duke Center for Human Genetics researcher William Scott, Ph.D., the study's first author. The team's findings will appear in the November 2003 issue of The American Journal of Human Genetics . The research was supported by the National Institute on Aging and the Alzheimer's Association. The study immediately follows another in which the Duke team identified a single gene that influences the age at onset of both Alzheimer's and Parkinson's diseases. © 2001-2003 Duke University Medical Center.

Keyword: Alzheimers; Genes & Behavior
Link ID: 4480 - Posted: 06.24.2010

NASHVILLE, Tenn. – When we experience an illusion, we usually have the impression we have been fooled, or that our minds are playing tricks on us. New research published in the Oct. 31 issue of the journal Science indicates our perceptions of these illusions are no hoax, but the result of how the brain is organized to process the information it receives from our senses. Vanderbilt University psychology department researchers Anna Wang Roe, Li Min Chen and Robert Friedman have identified responses in the brain to a touch illusion that shed new light on how the brain processes sensory information and call into question long-held theories about the nature of the “map” of the body in the brain. Walter Penfield is credited with first establishing in 1957 that a map of the human body exists in the brain, with specific areas of the cortex processing information from different body areas. Researchers have long hypothesized this map is a topographic map of the physical body.

Keyword: Pain & Touch
Link ID: 4479 - Posted: 06.24.2010

By BOB HERBERT A list of nearly 200 scientific researchers has been compiled and given to federal officials by the Traditional Values Coalition, a conservative group that goes wild over gay issues and federal funding of research related to human sexuality. The list, which has sent a chill through some researchers, is being used by the coalition and its government allies in attempts to discredit the researchers and challenge or revoke their federal grants. It's a sloppy, dangerous and wildly inaccurate list, put together by people who are freaked out by the content of the studies, and unconcerned about their value. The targeted studies cover a wide range of topics related to health and sexuality, including H.I.V. and AIDS, sexually transmitted diseases and adolescent sexual behavior. Copyright 2003 The New York Times Company

Keyword: Sexual Behavior
Link ID: 4478 - Posted: 11.04.2003

A wink and a nod flood men's saliva with testosterone. HELEN PEARSON Boy meets girl. Boy's sex hormone goes through the roof, finds a new study of lab-based flirting. James Roney and his team at the University of Chicago paid 18-36-year-old students $10 to come into the lab under the pretence of simply testing their saliva chemistry. Unbeknownst to the men, the scientists staged a five-minute chat with a twentysomething female research assistant. This brief brush set the men's hormones surging: testosterone levels in their spit shot up around 30%. And the higher a man's hormone soared, the more the female research assistant judged that he was out to impress - by talking about himself, for example1. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 4477 - Posted: 06.24.2010

Male apes share intense greetings only with close friends. JOHN WHITFIELD Want to show someone you really like them? Slap them in the face. That, at least, seems to be the message of baboon salutations. The closer the social bond between two animals, the more intrusive and risky the greeting when they meet. For male Guinea baboons (Papio papio), this involves ritualized fiddling with each other's genitals. Baboons impose on each other to demonstrate and test the strength of their relationship, says Jessica Whitham of the University of Chicago. The hazards involved in such intimacy mean that only truly trusting apes will get up close and personal, she says. © Nature News Service / Macmillan Magazines Ltd 2003

Keyword: Animal Communication; Evolution
Link ID: 4476 - Posted: 06.24.2010

An international team of researchers has identified the role of a gene which may explain why some people overeat and become obese. Their research, published today in Public Library of Science Biology, shows that the gene GAD2 has an appetite stimulating role, and that one form of the gene is strongly associated with obese people. While the researchers recognise that obesity is a result of the interactions of many genes and environmental factors, this is one of the first genes to be strongly touted as a candidate 'gene for obesity'. GAD2, which sits on chromosome 10, acts by speeding up production of a neurotransmitter in the brain called GABA, or gamma-amino butyric acid. When GABA interacts with another molecule named neuropeptide Y in a specific area of the brain - the paraventricular nucleus of the hypothalamus - we are stimulated to eat.

Keyword: Obesity
Link ID: 4475 - Posted: 11.03.2003

Overweight kids more likely to have behavior problems, national data show ANN ARBOR, MI - In a study that points to the importance of considering both mind and body in children's health, researchers report today that they have found a clear link between childhood obesity and behavior problems. Results published today in the journal Pediatrics show that children who have significant behavior problems, as described by their parents, are nearly three times as likely to be overweight as other children. In addition, children with behavior problems are as much as five times more likely to become overweight later. The study, done by a University of Michigan behavioral pediatrician and her former colleagues at Boston University, is based on national data from an intensive long-term survey of mothers and children conducted by the U.S. Department of Labor.

Keyword: Obesity
Link ID: 4474 - Posted: 11.03.2003

Spatially, functional magnetic resonance imaging is the gold standard, but poor temporal resolution has researchers looking for something better | By Leslie Pray According to legend, functional neuroimaging can trace its roots to the stroke of noon on a day in the late 19th century, when Italian physiologist Angelo Mosso observed a sudden increase in brain pulsation in his test subject, Bertino the peasant. Using an elaborate contraption, Mosso had been measuring the pulsations coming from a soft spot in Bertino's skull, the result of a head injury. Intrigued by the sudden pulsing, Mosso asked Bertino if the chiming of the local church bell had reminded him of his forgotten midday prayers. When Bertino said yes, his brain pulsated again. Then Mosso asked Bertino to multiply 8 by 12. Again, Bertino's brain pulsated. Thus was borne the notion that blood flow in the brain is related to cognition. That notion remains the basis of what some neuroscientists consider the most powerful in vivo brain imaging technology in use today, functional magnetic resonance imaging (fMRI). Since its emergence in 1992, fMRI has dominated the field of human brain mapping and has been featured in thousands of published papers--nearly an order of magnitude more than for any other functional imaging technique. For noninvasive whole-brain coverage in humans, fMRI's spatial resolution cannot be beat. And, unlike its historical predecessor, positron emission tomography, fMRI does not depend on dangerous ionizing radiation. Martin Lauritzen, professor of clinical neurophysiology at Denmark's Glostrup Hospital and the University of Copenhagen, says, "In a way, I think the fMRI is a perfect machine." But there are things that even a perfect instrument cannot do, such as record neuronal events in real time. More profoundly, the technique is limited by interpretational challenges; handling the enormous amount of data that even a single scan produces requires statistical skill, both to uncover deeper truths and to prevent erroneous conclusions. ©2003, The Scientist Inc.

Keyword: Brain imaging
Link ID: 4473 - Posted: 06.24.2010

Functional MRI offers a compelling neurological view, but of what? | By Mike May For centuries, philosophers and biologists alike dreamed of watching the brain operate to see its active response to sensations, actions, or even thoughts. In some ways, functional magnetic resonance imaging (fMRI) provides such a view. This technology essentially measures blood flow to areas of the brain, and presumably neural activity, in real time. The technique could help researchers specifically map the brain. The visual cortex, for example, appears to light up when a subject sees something. Still, scientists remain unsure about exactly what the signal, the flashing spots on an fMRI screen, actually mean. Indeed, neuroscientists debate what fMRI measures and how it can best be used clinically. Paul Matthews of the University of Oxford calls it "perhaps the single most important general technique in cognitive neuroscience." But, he cautions, "It is being widely used with relatively little understanding of its fundamental basis." ©2003, The Scientist Inc.

Keyword: Brain imaging
Link ID: 4472 - Posted: 06.24.2010

Gauging the effects of alcohol and nicotine on adolescent brains | By Harvey Black It seems that the adolescent brain may be particularly vulnerable to the effects of nicotine and alcohol. At a recent conference where researchers discussed published and unpublished work, studies showed that alcohol's impact on a variety of brain activities appears more severe in adolescent rats. Similarly, though results don't always agree, the adolescent brain also appears to be extremely sensitive to the effects of nicotine. Adolescent drinking in the United States exacts an enormous societal cost -- $53 billion (US) annually for such things as drunk driving accidents and violent crimes--according to a new study by the National Research Council and the Institute of Medicine.1 Thirty percent of US high school seniors "are drinking heavily, at least once a month," the report states, and nearly 70% of UK adolescents said they did likewise three times in the previous month, according to the report. Discussing as yet unpublished research, H. Scott Swartzwelder, neuropsychologist at Duke University, Durham, NC, said that the neurotransmitter gamma aminobutyric acid was more resistant to alcohol's effects in hippocampal slices from adolescent rats than from those in adult rats. GABA's release induces sedation, Swartzwelder explained. While these findings have not been replicated in humans, they have clear implications for adolescents. He discussed the results at a New York Academy of Sciences conference in September. ©2003, The Scientist Inc.

Keyword: Drug Abuse; Development of the Brain
Link ID: 4471 - Posted: 06.24.2010

Investigators seek the tick and tock of the brain's clock | By Jack Lucentini British novelist Aldous Huxley in a bid to study perception supposedly taped his conversations after swallowing the hallucinogenic drug mescaline. During one such chat, a researcher asked him to describe how time felt. "There seems to be plenty of it," was all Huxley could offer.1 Silly as that sounds, few have done much better in explaining time or its sensation. Yet scientists are taking the first stabs at answering at least one part of the question: how the brain perceives time. For example, a University of Washington study is the first to document how neurons in primates track time from one instant to the next.2 And even in a research field where no one knows what to expect, the investigations are turning up surprises. The findings cast some doubt on an idea that appeals to many, that the brain has an internal "clock" that somehow ticks ceaselessly away, providing a single reference frame for thoughts and actions.3 Instead, some researchers contend, time may be represented in many brain areas in a manner suited to each area's particular functions and inseparable from the decisions made there. Other researchers say the brain may use the same circuitry, or cells, to measure time, space, and magnitude. ©2003, The Scientist Inc.

Keyword: Biological Rhythms
Link ID: 4470 - Posted: 06.24.2010

Researchers revive age-old questions about mental illness etiology | By Brendan A. Maher It's a scary thought that one could develop a debilitating mental illness such as schizophrenia as easily as catching a cold. Well, it's more complicated than that, say advocates of the so-called infectious hypothesis, which states that viral and possibly bacterial infections occurring at critical points in brain development could increase the risk of mental illness. Everything from influenza to herpes simplex viruses to Toxoplasma gondii has been implicated in elevating risk for schizophrenia, perhaps indirectly through immunological reactions that change brain chemistry or wiring at key developmental stages. Raised, ridiculed, retracted, and rewrought, the hypothesis has morphed for nearly a century. Its current permutation may be gaining ground, though. With better epidemiological studies and animal work emerging, some former scoffers are beginning to accept the notion that, while not a direct cause, infections may factor into schizophrenia's complex gene/environment formula that dictates one's chances for landing somewhere among the less than 1% of people affected worldwide. The Stanley Research Institute's associate director of research, E. Fuller Torrey, has been a notorious proponent of infectious hypotheses since the 1970s. "I wouldn't say we're respectable, but it's no longer ridiculed, which seems like a step forward." BLAMING MOM Though most have eschewed the notion of a schizophrenogenic mother, a healthy environment does start in the womb. Various strands of evidence link increased propensity for schizophrenia to infections during gestation. Past studies uncovered a higher propensity in people born soon after known disease outbreaks such as the 1957 flu pandemic. Other data link increased risks to winter births or reported flu symptoms. ©2003, The Scientist Inc.

Keyword: Schizophrenia
Link ID: 4469 - Posted: 06.24.2010

PDF of a chart about schizophrenia.

Keyword: Schizophrenia
Link ID: 4468 - Posted: 11.03.2003

New studies explore the extensive pruning of axons and dendrites during nervous system development | By Douglas Steinberg A typical neuron's axons and dendrites, when loaded with dye and magnified, resemble long, untended tresses on an extremely bad hair day. They extend wildly, usually to one side, and then bend at weird angles as their ends split into branches and sub-branches. This neuronal coiffure must appear even more chaotic before the nervous system has undergone the developmental equivalent of a crew cut crossed with a topiary trimming. From the late embryonic to early postnatal stage, this pruning process drastically thins out the branches in many axonal and dendritic arbors. Long neuronal offshoots that grew to inappropriate targets simply vanish. Pruning occurs in probably all vertebrates and in many lower animals; neuroscientists have been aware of it for decades. Nevertheless, this phenomenon has garnered much less attention than that paid to other forces and events shaping the nervous system, such as axon guidance and apoptosis. The reason, researchers say, is that pruning is very hard to monitor and manipulate. ©2003, The Scientist Inc.

Keyword: Development of the Brain
Link ID: 4467 - Posted: 06.24.2010

Simple smell tests could help doctors identify people at risk of developing schizophrenia, a study suggests. It has long been known that people with schizophrenia or psychosis are unable to correctly identify smells. But until now scientists were unsure whether this occurred before or after symptoms developed. This latest study, published in the American Journal of Psychiatry, suggests it happens before the first symptoms appear. Dr Warrick Brewer and colleagues at the University of Melbourne examined a group of people, all of whom were deemed to have a very high risk of developing psychosis. They found those who went on to develop schizophrenia, rather than other forms of psychosis, were all unable to identify smells properly. (C) BBC

Keyword: Schizophrenia; Chemical Senses (Smell & Taste)
Link ID: 4466 - Posted: 11.02.2003

By LAUREN SLATER I'm sitting in a room with six terrified people. Outside the window we can hear the roar of Boston's rush hour, cars sputtering at intersections, baseball fans shouting in the streets. Out there it is loud, but in here, at the Center for Anxiety and Related Disorders at Boston University, it is as hushed as a hospital, the faces of the patients slick with sweat. The director of the center, the psychologist David H. Barlow, is one of the leading researchers in the field of fear. He isn't here today, but his methods are guiding this therapy group, which is led by two strikingly young-looking graduate students. It seems somehow fitting that this center, the premier institution for the treatment of anxiety, is located smack-dab in the maze of Boston's crooked and crazy streets. Barlow's method for treating anxiety disorders is surprisingly simple, although its philosophical and clinical implications are anything but. He aims to reduce anxiety not by teaching customary relaxation techniques involving calming mantras or soothing imagery, but by doing just the opposite: forcing the patient to repeatedly face his most dreaded situation, so that, eventually, he becomes accustomed to the sensation of terror. Barlow claims he can rid some people of their symptoms in as little as five to eight days. His treatment promises to be psychotherapy's ultimate fast track, but while many clinicians praise its well-documented results, others take a dimmer view of what one clinician calls ''torture, plain and simple.'' What critics malign as ''torture,'' Barlow calls ''exposure.'' Here's how it works. Ben, for instance, is 31 years old; he has come to the clinic to try to rid himself of panic attacks. His anxieties also stand in the way of his poetry writing, and he is fearful of people criticizing his work. One of his most feared situations is giving a public poetry reading and knowing that the audience is restless. Therefore, the patients and I are instructed to act as bored and rude as possible while Ben, hyped up on coffee, reads his poems aloud. ''Remember,'' says Molly Choate, one of the group leaders, ''as he reads, cough, whisper, laugh, rustle around.'' Copyright 2003 The New York Times Company

Keyword: Emotions; Stress
Link ID: 4465 - Posted: 11.02.2003

By KIRK JOHNSON The number of severe lead poisoning cases among children has sharply declined in New York City over the last 20 years as old peeling paint has been removed from apartments and homes. But thousands of children tested each year still have lead levels in their blood high enough to raise health concerns. At least part of the reason, city health officials and other experts say, may be the broader environment of the city itself: lead that is in the soil, on the streets and underneath dozens of miles of elevated subway, where the steel support structures were painted for decades with lead-based paint. Peeling and chipping indoor lead paint is almost certainly the prime threat to small children, who can eat the paint or breathe its dust, health experts agree. Copyright 2003 The New York Times Company

Keyword: Neurotoxins
Link ID: 4464 - Posted: 11.02.2003