TORONTO (Scientists at The Hospital for Sick Children (Sick Kids) and UCLA have pinpointed for the first time a region of the brain responsible for storing and retrieving distant memories. This research is reported in the May 7, 2004 issue of the journal Science. "It was previously known that the hippocampus processes recent memory, but that the hippocampus did not store memories permanently. We were able to determine that it is the anterior cingulate cortex where older, or lifelong, memories are stored and recalled," said Dr. Paul Frankland, the study's co-lead author, a scientist in the Sick Kids Research Institute, and assistant professor of physiology at the University of Toronto. The formation of new memories is thought to involve the strengthening of synaptic connections between groups of neurons. Remembering involves the reactivation of the same group, or network, of neurons. As memories age, the networks gradually change. Initially, memories for everyday life events appear to depend on networks in the region of the brain called the hippocampus. However, over time, these memories become increasingly dependent upon networks in the region of the brain called the cortex.

Keyword: Learning & Memory
Link ID: 5423 - Posted: 05.07.2004

Cooling the brain can minimise the risk of damage to babies deprived of oxygen at birth, research has confirmed. International tests of a special water cooled cap for babies' heads have produced highly promising results. Babies fitted with the cap were less likely to die, or to be severely disabled. Cerebral palsy rates were cut by half. However, the cap, developed by an international team of researchers, did not aid the most seriously injured. A lack of oxygen at birth can result from a ruptured uterus, a placenta that peels off too early, or the rupture or collapse of the umbilical chord. It is estimated that one in 1,000 babies in the UK are affected. The figure is much higher in the developing world. Up to now, no intervention has seemed to make much difference - many babies die or develop problems such as cerebral palsy. (C)BBC

Keyword: Development of the Brain; Stroke
Link ID: 5422 - Posted: 05.06.2004

By JANE E. BRODY A prominent Canadian researcher is facing claims that data in his widely reported study of a nutritional supplement's effects on thinking and memory in the elderly are so flawed as to have no real value. The scientist, Dr. Ranjit Kumar Chandra, is internationally known for his many contributions to the field of nutrition, and his work has been widely cited in professional and lay publications alike, including The New York Times. Scientific journals and three independent American scientists have raised questions about the validity of Dr. Chandra's findings, saying the study, published in September 2001 in the journal Nutrition, has statistical irregularities and inconsistencies, and is characterized by improbable research methods. The study purported to demonstrate striking cognitive benefits for people over 65 who took a daily multivitamin-mineral supplement that Dr. Chandra formulated and has since patented. He licensed the rights to the supplement to the Javaan Corporation, founded by his daughter, Amrita Chandra Gagnon. The company, in Somerville, Mass., sells the supplement as Javaan 50. Copyright 2004 The New York Times Company

Keyword: Learning & Memory; Alzheimers
Link ID: 5421 - Posted: 05.06.2004

By DONALD G. McNEIL Jr. Consumer groups called for a Congressional investigation yesterday into the death of a cow with symptoms of brain damage at a Texas slaughterhouse last week. The cow, which staggered and collapsed after passing an initial visual inspection at Lone Star Beef in San Angelo, Tex., was condemned as unfit for human consumption and under federal regulations should have been tested for mad cow disease. Instead, it was sent to a rendering plant to be made into animal food and byproducts. The Consumers Union, the Center for Food Safety and the Government Accountability Project said yesterday that they wanted Congress to look into why the cow was not tested and the possibility that federal officials ordered that no test be done. Consumer groups have regularly accused the Agriculture Department of trying to avoid finding more mad cow disease because of the damage it would do to the beef industry. Former beef industry officials hold high positions in the department. Copyright 2004 The New York Times Company |

Keyword: Prions
Link ID: 5420 - Posted: 05.06.2004

Most animals sniff, listen, and look to learn about the world around them. But weakly electric fish probe their environment using pulses or waves of electricity. Now, scientists have shown that the fish's electric sense is sharper than they'd realized: The fish can judge the shape and orientation of objects using electricity alone. Electric fish get their picture by generating an electric field and checking to see how it gets distorted. Objects that conduct electricity, such as other fish, warp the field differently than, say, rocks do. Scientists think the extra sense aids these stream-dwelling natives of Africa and South America in their nocturnal foraging. Previous work suggested that the fish can use touch and their electric sense to identify shapes. Now, a team of biologists and neuroscientists has shown that electricity alone is enough to size things up. In the 4 May issue of Current Biology, the researchers, led by Christian Graff of the Laboratoire de Biologie du Comportement in Grenoble, France, describe how they put the fish's electric sense to the test. The team trained six fish--three each of two species--to recognize virtual objects created by the interaction of the fish's electric field with electrodes in an aquarium maze. Depending on the pattern of connected electrodes, the fish would detect different arrangements of bars or planes oriented horizontally or vertically. Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Animal Migration; Animal Communication
Link ID: 5419 - Posted: 06.24.2010

Men are from Mars and women from Venus - except when they are in love. During this intense period, men and women become more like each other than at any other time. We already know that falling in love is a bit like going crazy. Donatella Marazziti of the University of Pisa in Italy showed in 1999 that levels of the neurotransmitter serotonin, which has a calming effect, dip below normal in those who say they are in love as well as in people with obsessive compulsive disorder. Both groups spend inordinate amounts of time obsessing about something or someone (New Scientist print edition, 31 July 1999). Now Marazziti has looked at the hormonal changes that occur in people who are in love. Her team measured the blood levels of several key hormones in 12 men and 12 women who said they had fallen in love within the past six months. The researchers compared these hormone levels to those in 24 other volunteers who were either single or in stable long-term relationships. The first finding was that both men and women in love have considerably higher levels of the stress hormone cortisol, indicating that courtship can be somewhat stressful. "But the most intriguing finding is related to testosterone," says Marazziti. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 5418 - Posted: 06.24.2010

Clinical trial will put probiotic bugs to the test. HELEN R. PILCHER Might a daily dose of friendly bacteria help treat autism? UK researchers hope probiotics will soothe the gut problems linked to autism and may even ease psychological symptoms. They are planning a clinical trial to test the idea. The proposed health benefits of probiotic bacteria are well known. The beneficial bugs are thought to out-compete other gut bacteria that can cause diarrhoea and ill health. So what is the link with autism? Up to 6 people in every 1000 develop the disorder, which involves difficulties with communication and social relationships, and many autistics also suffer from bloating, belly-ache and diarrhoea. Children with autism are known to have higher levels of one group of 'bad' bacteria, Clostridia, in their guts, explains Glenn Gibson from the University of Reading. So he hopes probiotic food supplements that lower levels of Clostridia will allay some symptoms of autism. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Autism
Link ID: 5417 - Posted: 06.24.2010

STANFORD, Calif. - College students with bipolar disorder appear to function well if properly diagnosed and treated, although those with a family history of the disease may be more difficult to treat, according to a recent analysis led by Terence Ketter, MD, associate professor of psychiatry and behavioral sciences at the Stanford University School of Medicine. "It's possible for this group of patients to do very well," said Ketter, who examined the medical and treatment histories of college students treated at Stanford's Bipolar Disorders Clinic. "It's important to realize that these students can function well if they get accurate diagnosis and treatment." Researchers on Ketter's team are presenting their findings during two sessions at the annual meeting of the American Psychiatric Association Meeting in New York. According to the National Alliance for the Mentally Ill, 2.3 million American adults have bipolar disorder, which is marked by episodes of mania and depression that typically begin in adolescence or early adulthood and can last from days to months. Family history is a powerful indicator; Ketter said a member of the general population on average has a 2 percent chance of having bipolar disorder while a person with a family history of the disease has a 20 percent risk.

Keyword: Schizophrenia; Depression
Link ID: 5416 - Posted: 05.06.2004

Finding confirms earlier result using better model for human alcohol abuse UPTON, NY — As a follow up to previous work showing that gene therapy can reduce drinking in rats trained to prefer alcohol, scientists at the U.S. Department of Energy’s Brookhaven National Laboratory have used the same technique to cut drinking in rats with a genetic predisposition for heavy alcohol consumption. The findings, along with additional results on the effects of long-term ethanol consumption on certain aspects of brain chemistry, are published in the May 2004 issue of Alcoholism Clinical and Experimental Research. “Though we are still early in the process, these results improve our understanding of the mechanism or mechanisms of alcohol addiction and strengthen our hope that this treatment approach might one day help people addicted to alcohol,” said Panayotis (Peter) Thanos, who lead the study in Brookhaven Lab’s medical department. Genetically predisposed alcohol-preferring rats are a much better model for human alcoholism than the rats used previously, which the scientists had to train to prefer alcohol. Without any training, the genetic alcohol-preferring rats drink, on average, more than five grams of ethanol per kilogram of body weight per day when given a free choice between alcohol and plain water. Genetically non-preferring rats, in contrast, typically consume less than one gram of ethanol per kilogram of body weight per day.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 5415 - Posted: 06.24.2010

By Brendan O'Neill Deleting memories is simple with computers, but as the movie Eternal Sunshine Of The Spotless Mind shows, it's still - as far as humans are concerned - the stuff of science fiction. Or is it? Charlie Kaufman's new film Eternal Sunshine of the Spotless Mind, tells the story of Joel (Jim Carrey), who has the memory of a soured relationship erased from his brain by a slightly sinister research organisation, Lacuna Inc. Lacuna carries out "cutting-edge, non-surgical procedures for the focused erasure of troubling memories." It even has its own website [see internet links] - though anybody looking to erase the memory of a lost love or traumatic accident should bear in mind that Lacuna Inc is fictional, the website is for film promotional purposes only, and the treatment it proposes is as yet the stuff of fiction. Or is it? American neuroscientists are currently developing "memory-management" drugs. They believe that such pills could help individuals improve their memory skills or even erase unwanted memories, such as that bad childhood experience lurking at the back of your mind. According to Eric Kandel, a Nobel Prize-winning memory researcher at Columbia University in Manhattan, memory-improving and memory-deleting medicines may be available within five to 10 years. More than 40 drugs aimed at improving memory are currently going through clinical trials with the US Food and Drug Administration. (C)BBC

Keyword: Multiple Sclerosis
Link ID: 5414 - Posted: 05.05.2004

At first glance, the differences between humans and other primates appear clear. Aside from hair and climbing skill, however, our big brains set us apart. Researchers Hansell Stedman and Nancy Minugh-Purvis of the University of Pennsylvania have stumbled on a slip up in a single gene found in our jaw muscles that they say may have triggered this divergence by enabling the brain case to expand. Their findings, published in Nature, have spurred a lively debate among anthropologists and evolutionary biologists alike, giving them a new reason to ruminate our possible origins. While studying human muscle disease, Stedman, a gastrointestinal surgeon, found a new version of a gene that encodes for a muscle-fueling protein called myosin. "Myosin is the most abundant protein in muscle," explains Stedman. "It's the motor protein that generates all the force. The body is able to make a wide range of different myosins, and each one has a different gene. The surprise came in finding that one of them…winds up having a mutation that cripples its ability to make a functional myosin…in all humans, as far as we can tell." © ScienCentral, 2000-2004.

Keyword: Evolution
Link ID: 5413 - Posted: 06.24.2010

Political debates about same-sex unions are likely to be with us for quite some time, but what does science have to say about sexual orientation? In recent years, some scientists have looked to other species to try to understand whether there may be a biological basis for same-sex preference. The latest such study links same-sex preference to differences in brain structure in male sheep, and its authors and others say it confirms a controversial human brain study published back in 1991. The new sheep study, published in the February 2004 issue of the journal Endocrinology, resulted from ongoing USDA research seeking to improve breeding productivity. Sheep breeders have long known that a minority—between six and ten percent—of rams prefer to attempt to mate with other rams instead of ewes. "Research was done on these animals for the last 20 years in terms of their reproductive behaviors and their endocrinology," says Charles Roselli, professor of physiology and pharmacology at Oregon Health and Science University. "There was never a consensus whether the behavior was caused by any aspect of rearing or anything like that, but there were reports that their brains might be different." © ScienCentral, 2000-2004.

Keyword: Sexual Behavior
Link ID: 5412 - Posted: 06.24.2010

Large-breasted, narrow-waisted women have the highest reproductive potential, according to a new study, suggesting western men's penchant for women with an hourglass shape may have some biological justification. Women with a relatively low waist-to-hip ratio and large breasts had about 30 per cent higher levels of the female reproductive hormone estradiol than women with other combinations of body shapes, found Grazyna Jasienska, at Jagiellonian University in Krakow, Poland and colleagues. Two of the team, Peter Ellison and Susan Lipson at Harvard University in the US, have previously shown that higher levels of estradiol are indeed related to higher fertility in women trying to get pregnant. "If there are 30 per cent higher levels, it means they are roughly three times more likely to get pregnant," Jasienska, a human biologist, told New Scientist. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Evolution
Link ID: 5411 - Posted: 06.24.2010

GAINESVILLE, Fla. --- What's a little male fish's secret weapon for attracting the lady fish? Something some guys but few other males in the animal kingdom have thought of: It acts like a good dad. Sand gobies, small fish native to the European coast, are among about 20 percent of fish families worldwide that display some form of care for eggs or hatchlings. But in experiments reported in the current issue of the journal Behavioral Ecology, a team that includes a University of Florida scientist reports that male sand gobies work harder at building nests and taking care of eggs when females are present – the first time such "courtship parental care" has been documented in any species. Some males' behavior was even more dastardly. While the experiments showed all male gobies nibbled on the eggs in their charge, unaccompanied males not only shirked their parental duties – they also were more likely to gobble down entire clutches of eggs.

Keyword: Sexual Behavior; Evolution
Link ID: 5410 - Posted: 06.24.2010

In an article appearing in the May 5 issue of the Journal of the American Medical Association (JAMA), addiction researchers at the National Institutes of Health compared marijuana use in the U.S. adult population in 1991-92 and 2001-02. They found that the number of people reporting use of the drug remained substantially the same in both time periods, but the prevalence of marijuana abuse or dependence increased markedly. This new study showed that increases in the prevalence of abuse or dependence were most notable among young African-American men and women and young Hispanic men. This is the first study to assess long-term trends in marijuana abuse and dependence in the United States using the most up-to-date classification system-the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). The researchers from the National Institute on Drug Abuse (NIDA) and the National Institute on Alcohol Abuse and Alcoholism (NIAAA) compared trends in marijuana use, abuse, and dependence using the DSM-IV categories. The DSM defines marijuana abuse as repeated instances of use under hazardous conditions; repeated, clinically meaningful impairment in social/occupational/educational functioning; or legal problems related to marijuana use. Marijuana dependence is defined as increased tolerance, compulsive use, impaired control, and continued use despite physical and psychological problems caused or exacerbated by use.

Keyword: Drug Abuse
Link ID: 5409 - Posted: 05.05.2004

A team at the University of Rochester has found that the human brain makes much more extensive use of highly complex statistics when learning a language than scientists ever realized. The research, appearing in a recent issue of Cognitive Psychology, shows that the human brain is wired to quickly grasp certain relationships between spoken sounds even though those relationships may be so complicated they're beyond our ability to consciously comprehend. "We're starting to learn just how intuitively our minds are able to analyze amazingly complex information without our even being aware of it," says Elissa Newport, professor of brain and cognitive sciences at the University and lead author of the study. "There is a powerful correlation between what our brains are able to do and what language demands of us." Newport and Richard Aslin, professor of brain and cognitive sciences, began by looking at how people are able to recognize the division between spoken words when spoken language is really a stream of unbroken syllables. They wanted to know how it is that we perceive breaks between spoken words, when in fact there are no pauses. This is why it often seems as if speakers of foreign languages are talking very quickly; we don't perceive pauses.

Keyword: Language
Link ID: 5408 - Posted: 05.05.2004

Scientists believe they may have found the reason why humans suffer from jet lag. They believe we have two timekeeping centres in our brains - one sticks to the clock, the other is influenced by cues such as sunrise and nightfall. Researchers, writing in Current Biology, believe jet lag results when these centres don't marry up. The University of Washington team believe it may be possible to develop a drug to tackle the problem. Researcher Dr Horacio de la Iglesia said: "If we can discover how the two parts of the brain are synchronised we might be able to find mechanisms to treat jet lag." A tiny area of the brain called the suprachiasmatic nucleus (SCN) is thought to control sleep, hormone and temperature rhythms in the body. It is this area, it is thought, which responds to external factors such as sunrise. However, other characteristics stick more closely to regimented 24-hour cycles - suggesting the presence of another timekeeping centre - possibly within the same tissue - that is unaffected by external cues. (C)BBC

Keyword: Biological Rhythms
Link ID: 5407 - Posted: 05.04.2004

By ANAHAD O'CONNOR For most people taking antidepressants, the risk of a diminished sex drive may seem like a worthwhile sacrifice for the benefits from the drugs. Up to 70 percent of patients on antidepressants report sexual side effects, yet the number of Americans who take the drugs has ballooned since Prozac was introduced in the late 1980's. Last year, studies show, doctors in the United States wrote 213 million prescriptions for antidepressants. But what if the sexual side effects of the drugs, often considered little more than a nuisance, had more serious consequences, impairing not only sexual desire in some people, but also the ability to experience romance? The question, which experts are beginning to ask, was at the center of a talk this weekend at the annual meeting of the American Psychiatric Association in New York. Dr. Helen E. Fisher, an anthropologist at Rutgers, presented findings that suggest, she says, that common antidepressants that tinker with serotonin levels in the brain can also disrupt neural circuits involved in romance and attachment. Copyright 2004 The New York Times Company

Keyword: Depression; Sexual Behavior
Link ID: 5406 - Posted: 05.04.2004

By DENISE GRADY By the time Linda Culpepper found her way to the Vanderbilt University Medical Center, she was in an alarming state. Her hair was falling out, her skin was flaking, and her muscles had wasted so much that it was hard for her to walk. She had frequent attacks of diarrhea, and could rarely eat without vomiting. "She was a shadow of a human being," said her daughter, Susan Gritton. Dr. Gordon L. Jensen, director of the Vanderbilt Center for Human Nutrition in Nashville, diagnosed her condition as life-threatening malnutrition, admitted her to the hospital and ordered intravenous feeding immediately. The cause of the malnutrition was complications from weight-loss surgery performed at another hospital, specifically a gastric bypass, a procedure that closes most of the stomach and shortens the small intestine, often leading to weight losses of 100 pounds. That is the operation that has strikingly transformed celebrities like Al Roker, the television weather forecaster; Carnie Wilson, the singer; and Roseanne Barr, the comedian. Copyright 2004 The New York Times Company

Keyword: Obesity
Link ID: 5405 - Posted: 05.04.2004

Scientists wowed by species' adaptations, survival skills Keay Davidson, Chronicle Science Writer "Now, what's the one thing we have to remember about the ocean?" the father fish asks little Nemo in the film "Finding Nemo." Reply: "It's not safe." "That's my boy." Real-life sea creatures aren't simply passive victims of oceanic threats; rather, they can fight back, so to speak. For every whale that beached itself after being confused by boating noise, or every marine mammal or sea turtle killed by reckless fishermen or boaters, countless others survive, thanks to their natural defenses -- defenses of which scientists were ignorant until recently. The latest issue of the journal Nature reports on a variety of cunning ways that sea creatures evade oceanic dangers. As sailors and divers know, it's easy to get lost in the vast ocean. But according to a study by biologists in North Carolina and Florida, sea turtles find their way to distant points with "pinpoint accuracy" thanks to a built-in brain "map" attuned to variations in the local terrestrial magnetic field. ©2004 San Francisco Chronicle

Keyword: Hearing; Animal Migration
Link ID: 5404 - Posted: 06.24.2010