Men and women's brains respond to pain differently, researchers have found. Scans showed parts of women's brains linked to emotion were stimulated when they felt pain. But the researchers, from the University of California Los Angeles (UCLA) found that, in men's brains analytical areas showed greater activity. They say the study of people with irritable bowel syndrome (IBS) could help the development of targeted treatments for the illness. IBS causes discomfort in the abdomen and diarrhoea or constipation. The UCLA researchers carried out positron emission tomography (PET) brain scans of 26 women and 24 men, while they experienced a small amount of pain. (C) BBC

Keyword: Sexual Behavior; Pain & Touch
Link ID: 4495 - Posted: 11.06.2003

NewScientist.com news service Copulating cockerels show "unprecedented sophistication" in the way they dole out their sperm, suggests a new study. The findings by Swedish and British researchers challenge the view that males use a straightforward reproduction strategy to simply mate with as many females as possible. Male fowl devote considerably more sperm to their first encounter with a new mate than with a familiar one, the study reveals. They will also increase the sperm delivered if rival males are around. And an attractive hen - with a large comb adorning her head - will receive more sperm than a less attractive female. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Evolution
Link ID: 4494 - Posted: 06.24.2010

Males of the species Gallus gallus are hardly gallant. A male wild chicken scatters his seed among females according to his own sense of the competition, according to new research. The results indicate that the males have evolved a sophisticated way to choose where to put their resources. Hens who mate the rounds end up with sperm from more than one competing rooster. For a rooster to win at this game, he has to contribute more sperm than the other guys. But willy-nilly inseminating is costly and time consuming--a rooster might run out of sperm before the best hen waltzes his way. Evolutionary biologist Tommaso Pizzari at the University of Leeds, U.K., and colleagues wondered if the wild roosters hedge their bets by inseminating some females with more sperm than others. Pizzari and company fitted the hens with films on their cloacas to collect the sperm deposited by roosters. Then the team set up a mating ring in full view of an adjacent pen. The researchers allowed one male at a time to mate with the hen, watched by up to three other males to simulate competition for the mate. When a dominant rooster competed with just one voyeur, he ejaculated less sperm than when competing with three males, indicating that roosters consider how many suitors a female has. Subdominant males, on the other hand, apparently forfeit the most competitive situations and send out the most swimmers when they’re competing against just one other male, the team reports in the 6 November issue of Nature. Copyright © 2003 by the American Association for the Advancement of Science.

Keyword: Sexual Behavior; Evolution
Link ID: 4493 - Posted: 06.24.2010

A new study cautions that drugs being designed to enhance some forms of memory in the elderly may actually worsen working memory, such as the cognitive ability to hold a phone number in mind long enough to dial it. The research, published online in Neuron on November 5, analyzes the effects of these drugs on multiple brain regions and suggests that the medications may actually have hazardous consequences on higher-order thought processes that are regulated by the prefrontal cortex. The hippocampus has been associated with long-term memory formation, while the prefrontal cortex has been associated with working memory. In a healthy brain, the two brain systems work together to optimize cognitive abilities. Compounds that increase the activity of an enzyme called protein kinase A (PKA) improve long-term hippocampal-dependent memory in aged mice and have been proposed as possible therapeutics for memory deficits in elderly humans.

Keyword: Alzheimers; Learning & Memory
Link ID: 4492 - Posted: 11.06.2003

VANCOUVER, CANADA — Millions of HIV patients who suffer from dementia now have hope of a treatment, thanks to a breakthrough discovery by Canadian researchers. Scientists from the University of Calgary in Alberta and the University of British Columbia in Vancouver have found that HIV triggers an enzyme in white blood cells that kills nerve cells in the brain. The enzyme, known as Metalloproteinase-2 or MMP2, changes a molecule required for normal brain growth and function. The altered molecule becomes highly toxic and destroys brain nerve cells, giving rise to symptoms of dementia. It is the first study to unravel the mechanics of how dementia and memory loss is caused in HIV patients. In addition, the researchers also found they could block the toxic effects of MMP2 by using drugs already in clinical trials for cancer treatment. © Copyright The University of British Columbia,

Keyword: Miscellaneous
Link ID: 4491 - Posted: 06.24.2010

Middle-aged men now have a good excuse to go to the pub with their mates - it is good for their brains. Researchers say that social activities, such as evening classes, chess and even going to the pub can help maintain mental agility. Middle-aged women appeared to benefit slightly less from the same activities. The team from University College London say their work shows that people should not simply resign themselves to losing cognitive skills as they age. Researchers questioned about 5,350 civil servants aged between 35 and 55 about their leisure habits. They were asked if they participated in any of 13 activities, ranging from those which required a low cognitive effort - such as DIY and housework - to those which required high cognitive effort - such as cultural visits and evening classes. (C) BBC

Keyword: Alzheimers; Learning & Memory
Link ID: 4490 - Posted: 11.05.2003

Are teenage girls more stressed than boys? As this ScienCentral News video reports, researchers are examining the relationship between their sex hormones and their brains for clues. Some adults may think youth is wasted on the young, but teenagers actually face a multitude of stressful situations on a daily basis. "As adults we like to think that we have the most stress, but that's probably not true," says Elizabeth Young, professor of psychiatry and research scientist at the University of Michigan Mental Health Research Institute . "Not doing well in school, having problems with your friends, parents, boyfriends, girlfriends, those are all things that are well known to have big effects on causing depression." Teenagers, Young says, "have a lot more of these life changes than those of us who are in stable relationships and are raising a family." © ScienCentral, 2000-2003.

Keyword: Stress; Hormones & Behavior
Link ID: 4489 - Posted: 06.24.2010

New research into depression is showing that antidepressants are not only changing the chemicals inside the brain, they actually make the brain grow new cells. As this ScienCentral News video reports, the new findings may lead to improved treatments against depression. One in ten adults suffers from depression in any given year. Many of them get relief from antidepressants, but they usually take a long time to work and often have troubling side effects. Now a study at Columbia University shows that these drugs don't work the way scientists have thought. Neuroscientists have long believed that a shortage of a brain chemical called serotonin causes depression, so most antidepressants were tailored to raise serotonin levels in the brain. But some researchers have suspected that antidepressants do more than that. Together with his coworkers, René Hen, professor of pharmacology at Columbia, has now proven that antidepressants actually stimulate the growth of new brain cells, which turns out to be necessary for recovery from depression. © ScienCentral, 2000-2003.

Keyword: Depression; Neurogenesis
Link ID: 4488 - Posted: 06.24.2010

Babies born to women who suffer post-natal depression are more likely to become violent and aggressive children, research suggests. Cardiff University researchers followed children up to the age of 11 from 122 families in urban south London. They found boys with mothers who were depressed three months after birth were more likely to get into fights and be suspended from school. The research is published in the journal Developmental Psychology. The Cardiff team found that children were most likely to be badly behaved if their mothers had suffered repeated bouts of depression. They interviewed mothers during pregnancy, three months after the birth, and when the child was one, four and 11 years old. (C) BBC

Keyword: Depression; Aggression
Link ID: 4487 - Posted: 11.04.2003

Daniel W. McShea Darwin and Design: Does Evolution Have a Purpose? Michael Ruse. x + 371 pp. Harvard University Press, 2003. $29.95. Eyes are for seeing; leaves are for capturing sunlight; the plates on the back of Stegosaurus may have been for radiating heat. For at least 2,000 years, from Plato until Darwin, these contrivances of organisms were considered strong evidence for the existence of a higher power. They are functional, seeming to exist because they serve a purpose, like human artifacts, especially machines. Before Darwin, the only way imaginable for a purposeful device to arise was by design—that is, for it to be produced intentionally, by a mind like ours. And thus it seemed reasonable to conclude that such functional features of organisms must be the product of a divine designing mind. In 1802, this argument was proffered compellingly by one of the foremost exponents of natural theology, William Paley. He argued that if one stumbles on a stone in a field, one can say very little about its origins; but if one finds a watch, it is immediately clear that "its several parts are framed and put together for a purpose." Paley went on to argue that a purposeful watch requires a watchmaker, and that the equivalent functional complexity of organisms likewise requires a higher power, a designing mind. A half-century later Charles Darwin demolished this 2,000-year-old argument, showing that an unthinking process, natural selection, could produce function and therefore the appearance of design. In the Darwinian view, of course, function arises iteratively, beginning with chance modification, followed by preservation of those modifications that promote survival and reproduction, further chance modification, and so on. Thus, in effect, the functional structures of an organism exist because of their past contributions to reproductive success. No intentionality, no designing mind, is required.

Keyword: Evolution
Link ID: 4486 - Posted: 06.24.2010

As pharmaceutical companies push their products, more and more kids are being treated with powerful -- and untested -- adult drugs. By Helen Cordes For Dr. Stephen Borowitz, the most frustrating office visits are with parents of kids suffering from stomachaches and infants prone to spitting up. Often, he says, the parents already know what they want -- adult heartburn drugs such as the "purple pill," Prilosec. "I tell them about nondrug tactics that often help the symptoms," says Borowitz, a professor of pediatric gastroenterology at the University of Virginia. "But they want their kids to have the pills they've seen on TV." Borowitz and other experts worry about the safety of using potent adult drugs to ease common childhood ailments. But their warnings are unlikely to be heeded by most doctors and parents -- thanks, in large part, to an aggressive marketing campaign by pharmaceutical companies. Nearly a quarter million children took Prilosec in 2000, according to U.S. Food and Drug Administration documents, and nearly 100,000 were prescribed similar "proton pump inhibitor" (PPI) heartburn drugs such as Prevacid, Nexium, Protonix, and Aciphex. None of these PPIs were approved for pediatric use at the time (Prevacid finally secured approval in 2002), and the FDA had warned that children taking Prilosec could face risks of pancreatitis and liver problems. Yet drugmakers have continued to fund medical conference presentations, publications, and tutorials touting PPIs as "highly effective and safe" for children. And this January, tap Pharmaceuticals (which makes a strawberry-flavored version of Prevacid) sponsored a nationwide campaign featuring best-selling baby-book author Dr. Bill Sears to publicize what it calls "one of the most common esophageal disorders in children" -- gastroesophageal reflux disease, or GERD. It's a claim that angers Borowitz, who says there is no evidence of a GERD epidemic. PPIs may be useful in a few "relatively rare" conditions, he says; but too often, "ordinary childhood problems are pathologized into a disease." © 2003 The Foundation for National Progress

Keyword: Depression; ADHD
Link ID: 4485 - Posted: 06.24.2010

By ANAHAD O'CONNOR For many, a diagnosis of Alzheimer's disease can mean life in a dreary nursing home and a treatment centered on powerful antipsychotics to combat the onset of memory loss, dementia and other signs of a mind that is slowly unraveling. But now, some scientists say the best way to treat Alzheimer's is with a broader approach — one that emphasizes regular exercise and a healthy environment. Even encouraging participation in an activity as simple as gardening, one researcher noted, can reduce depression and ease anxiety in some Alzheimer's patients. The findings were detailed in two studies released last month. Copyright 2003 The New York Times Company

Keyword: Alzheimers
Link ID: 4484 - Posted: 06.24.2010

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