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Role of alcohol, marijuana and cigarettes among other factors being examined BUFFALO, N.Y. -- In a new study underway at the University at Buffalo's Research Institute on Addictions, researchers are examining the cumulative effect of a number of risk factors associated with mothers' cocaine use on their infants' mental development. Maternal substance use, an environment of family and community violence, negative mother-infant interactions and maternal psychological problems such as depression are being considered in the study, as well as the impact of these risk factors on infants' physiology and behavior. Given the reality that most cocaine-using women also use substances such as alcohol, marijuana and cigarettes, the investigators are looking at the role of these other substances, in addition to cocaine use.

Keyword: Drug Abuse; Development of the Brain
Link ID: 821 - Posted: 10.20.2001

WASHINGTON - Does coming from a family full of "lefties" tend to make a person better at remembering events? The data from two recent experiments answer in the affirmative. What's more, psychologists may finally be able to explain why kids don't remember events until they are about four years old. This recent research is reported in the October issue of Neuropsychology, published by the American Psychological Association (APA). Stephen D. Christman, Ph.D., and Ruth E. Propper, Ph.D., of the University of Toledo in Ohio, studied memory as a function of family handedness. Interestingly, people don't have to be personally left-handed to share a unique trait: There is evidence that the two brain hemispheres of even right-handers with left-handed relatives share functions more equally, interact more and are connected by a larger corpus callosum (the bundle of mediating fibers) than the hemispheres of people with right-handed relatives. Although it is not well understood, there is a hereditary component to handedness. "Superior Episodic Memory is Associated with Interhemispheric Processing," Stephen D. Christman, Ph.D., and Ruth E. Propper, Ph.D., Neuropsychology, Vol. 15, No 4. © PsycNET 2001 American Psychological Association

Keyword: Laterality; Learning & Memory
Link ID: 820 - Posted: 10.20.2001

Although scientists believe that mad cow disease spread from cattle to people in a few instances in the United Kingdom, they know very little about how that happened. To better understand how diseases like mad cow jump and adapt to a new species, researchers at the National Institute of Allergy and Infectious Diseases (NIAID) examined the process by which a disease called scrapie transfers from hamsters to mice. "We found that the adaption is a prolonged and subtle process, and the early stages of it are very difficult to detect," says Bruce Chesebro, M.D., senior study author and researcher at NIAID's Rocky Mountain Laboratories (RML) in Montana. The results of his team's work are reported in the current issue of the Journal of Virology.

Keyword: Prions
Link ID: 815 - Posted: 10.20.2001

The finding that "Estrogen receptor-{alpha} antisense decreases brain estrogen receptor levels and affects ventilation in male and female rats," is the result of an investigation conducted by Shashita R. Inamdar, Kathleen M. Eyster, and Evelyn H. Schlenker, all of the Division of Basic Biomedical Sciences at the University of South Dakota School of Medicine, Vermillion, SD. Dr. Inamdar and colleagues explored the effects of estrogen receptor-{alpha}protein production in the brain of neonatal rats on the gender-specific ventilatory response to aspartic acid. To determine whether the activational effects of puberty modified these responses to aspartic acid the investigators evaluated animals shortly after weanling (~23 days old) and at adulthood (2-3 months old).

Keyword: Hormones & Behavior
Link ID: 813 - Posted: 10.20.2001

Bijal P. Trivedi for National Geographic Today Researchers in England have identified the first gene to be linked to language and speech, suggesting that our human urge to babble and chat is innate, and that our linguistic abilities are at least partially hardwired. "It is important to realize that this is a gene associated with language, not the gene," said Anthony Monaco of the University of Oxford, England, who led the genetic aspects of the study. The gene is required during early embryonic development for formation of brain regions associated with speech and language. The gene, called FOXP2, was identified through studies of a severe speech and language disorder that affects almost half the members of a large family, identified only as "KE." Individuals with the disorder are unable to select and produce the fine movements with the tongue and lips that are necessary to speak clearly. © 2001 National Geographic Society. All rights reserved.

Keyword: Language; Genes & Behavior
Link ID: 811 - Posted: 10.20.2001

See how you compare with other Discover readers By Eric Haseltine Inexorably, after the age of thirty, your brain begins to shrink. The rate that cerebral tissue vanishes differs from one person to the next based upon lifestyle, education, sex, disease and other factors. However, the diminishment of cognitive abilities associated with age-related brain shrinkage affects virtually everyone. One of the most sensitive tests of brain aging is the Trailmaking test. © Copyright 2001 The Walt Disney Company.

Keyword: Development of the Brain
Link ID: 809 - Posted: 10.20.2001

It seems like voodoo, but altering electrical currents in the brain may help treat depression, epilepsy, and Parkinson's disease By Karen Wright Photographs by Brian Finke Electroconvulsive therapy, or shock therapy, is the most effective treatment known for severe depression. A strong electrical current applied to the skull triggers epilepticlike seizures that somehow jolt the mind free of melancholy. But shock treatment is a famously blunt instrument. It requires the use of general anesthesia, often causes memory loss and confusion, and can bring on a headache that rivals the worst hangover. An ideal version of electroconvulsive therapy would dispense with the seizure and the side effects. It would target only those areas of the brain involved in depression. It would be easy to administer, and it wouldn't hurt. In short, the procedure would look a lot like transcranial magnetic stimulation (TMS), a kinder, gentler way of jolting the brain that is winning the enthusiasm of clinicians and basic researchers alike. Though still unproven, TMS holds promise as an alternative treatment for a number of psychiatric disorders, as well as epilepsy, Parkinson's disease, and even writer's cramp. It's already helping to map the circuitry of the normal brain and reveal faulty wiring. © Copyright 2001 The Walt Disney Company

Keyword: Epilepsy; Depression
Link ID: 808 - Posted: 10.20.2001

SAN DIEGO--A neurodegenerative disorder commonly afflicting people over age 50, Parkinson's disease has so eluded geneticists that many have pronounced it noninherited. At the annual meeting of the American Society for Human Genetics, a group of researchers report that late-onset Parkinson's does have a genetic component, which they map to chromosome 1. Researchers had previously found eight genetic loci, mostly associated with a less common, early-onset form of Parkinson's, but family studies of the late-onset version have generally come up empty. Even in identical twins, the disease may occur up to 20 years later in one twin than the other. And because symptoms appear late in life, people may die of other causes before Parkinson's shows up, making it difficult to track heritability. In Iceland, a biotechnology company called deCODE Genetics is tapping extensive genealogical records, which date back 10 generations to the island's original settlers. Most of the 275,000 living Icelanders are descended from these settlers and are genetically very similar. Copyright © 2001 by the American Association for the Advancement of Science.

Keyword: Parkinsons; Genes & Behavior
Link ID: 806 - Posted: 10.20.2001

JOHN WHITFIELD
The American writer Gore Vidal once said that he never passed up an opportunity to have sex or appear on television. Some male birds would disagree on at least one count. Having mated with a female, a great snipe will reject her further advances and even violently chase her away. Male great snipe (Gallinago media) form leks - groups of males that defend small territories for strutting their stuff. Females come to leks - nature's nightclubs - to eye up the talent before choosing a mate. 1.Sæther, S. A., Fiske, P. & Kalas, J. A. Male mate choice, sexual conflict and strategic allocation of copulations in a lekking bird. Proceedings of the Royal Society London B 268, 2097-2102 (2001). © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Sexual Behavior
Link ID: 805 - Posted: 10.20.2001

XAVIER BOSCH
A strict high-fat, low-carbohydrate, calorie-restricted diet reduces seizures in children with intractable epilepsy. So concludes the largest and longest trial of an eating plan that was first suggested almost a century ago. For about two years, epileptic youngsters on a 'ketogenic diet' eat 25% less than normal and consume 90% of their daily calories as fats. They take vitamins and minerals to avoid malnutrition and their condition is monitored by a doctor and a dietician. There is currently a resurgence of interest in the diet, which was eclipsed by the development of anticonvulsant drugs. 1.Hemingway, C., Freeman, J. M., Pillas, D. J. & Pyzik, P. L. The ketogenic diet: a 3- to 6-year follow-up of 150 children enrolled prospectively. Pediatrics 108, 898-905 (2001). 2.Kwan, P. & Brodie, M. J. Early identification of refractory epilepsy. New England Journal of Medicine 342, 314-319 (2000) © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Epilepsy
Link ID: 804 - Posted: 10.20.2001

Growing fat cells and nerve cells in the same dish has produced what is believed to be the first demonstration of two-way communication between the cell types. The achievement, using rat and mouse cells, provides the first clear evidence that signals from fat cells can directly influence neurons outside of the brain, the researchers say, with implications for understanding the storage and burning of fat, obesity and related disorders, such as diabetes. "It's been known for a long time that neurons outside of the brain communicate to fat cells, but no one has thought much about whether fat cells can signal back to the neurons," says first author Christine Turtzo, an M.D.-Ph.D. candidate at The Johns Hopkins University School of Medicine. "We now have evidence that fat cells directly signal neurons and influence their behavior. Unless you had both types of cells growing together, you would not know." Previously, fat cells were only known to influence the brain by producing substances that would be carried through the blood stream. The brain was known to control the burning of fat and to respond to its signals by sending messages through the spinal cord and out to nerves located in and around the fat deposits. The study shows that fat and nerve cells can influence each other without direction from the brain.

Keyword: Obesity
Link ID: 803 - Posted: 10.20.2001

CHAPEL HILL -- Using specially designed and bred laboratory mice, scientists at the University of North Carolina at Chapel Hill have discovered that a well-known protein in the body called tumor necrosis factor-alpha plays a central role in how nerves and the brain repair themselves. The discovery is a surprise, the UNC School of Medicine researchers say, because the protein, a cytokine produced during inflammation, has traditionally been considered something that makes illnesses worse, not better. Taking advantage of the new knowledge potentially could lead to more effective treatments for such illnesses as multiple sclerosis. "We're far from using this in any way to help patients directly, and we don't want to get hopes up prematurely," said Dr. Jenny P.-Y. Ting, Alumni Distinguished professor of microbiology and immunology at the Lineberger Comprehensive Cancer Center and the neurobiology curriculum. "Still, this is a different way of thinking about remyelination that undoubtedly will be useful and important in the future.

Keyword: Multiple Sclerosis
Link ID: 802 - Posted: 10.20.2001

Greater Exposure to Light Lowers Melatonin Production and Increases Estrogen Levels By Susan Okie Washington Post Staff Writer Women who work nights and those who are up frequently during the early hours of the morning may be at increased risk for developing breast cancer, according to the results of two studies published today. The findings, combined with those of other studies in humans and in animals, suggest that nighttime exposure to light may elevate breast cancer risk by suppressing production of melatonin, a brain hormone that is made during darkness and that normally peaks at night. Scientists who performed the research cautioned that the conclusions are preliminary and said they cannot yet quantify the degree of risk or assess the practical implications for women. "It's really premature at this stage to . . . begin to make recommendations to individual women about changes in behavior as drastic as changing their job," said Scott Davis, a professor of epidemiology at the University of Washington in Seattle, who led one of the research teams. © 2001 The Washington Post Company

Keyword: Biological Rhythms; Hormones & Behavior
Link ID: 801 - Posted: 11.06.2001

Some amputees experience phantom pain The pain that amputees experience in their stumps comes from a different source than the pain that some experience from phantom limbs, research suggests. Up to 80% of all amputees experience pain in their stumps or what feels like the missing limbs long after surgical wounds have healed. Researchers from Johns Hopkins University in Baltimore have carried out tests that show that the two types of pain have different sources. Their work gives doctors clues as to what type of pain relief medication is best for amputee patients. (c) BBC

Keyword: Pain & Touch
Link ID: 800 - Posted: 10.20.2001

The National Center for Research Resources (NCRR), a component of the National Institutes of Health, has awarded more than $20 million to a consortium of universities coordinated by the University of California, San Diego (UCSD) to build the first nationwide high-performance computer environment to study diseases of the brain. Researchers linked over a high-speed network will share high-resolution animal and human brain images to allow analysis and comparison at many different scales. These capabilities will be the means for cross-institutional integration of data and expertise that can advance research on such brain-related diseases as multiple sclerosis, schizophrenia, Alzheimer's disease, and Parkinson's disease. "Biomedical research is undergoing a rapid transformation that can be traced to the explosion in the size of data sets ranging from DNA and protein sequences to high-resolution images mapping the architecture of cellular components, cells, tissues, organs, and whole organisms," said Judith Vaitukaitis, director of NCRR. "Information technology is becoming essential for management and analysis of these data." The Biomedical Informatics Research Network (BIRN), will be the nation's first test bed for sharing and mining data effectively in a site-independent manner for both basic and clinical research.

Keyword: Miscellaneous
Link ID: 799 - Posted: 10.20.2001

Neuropeptides are peptides that are found in neural tissue. Previous research found that a gene variant of the neuropeptide Y (NPY) was linked with higher average alcohol consumption. A new study has found a higher prevalence of the NPY variant among social drinkers than among alcoholics. Researchers speculate the NPY variant may retard instead of predispose the transition to alcoholism. Numerous studies have demonstrated that genetic factors can at least partially determine vulnerability to alcohol dependence. It remains unclear, however, which genes are involved and what their roles are. Neuropeptides are peptides that are found in neural tissue. An earlier study found that a gene variant of the neuropeptide Y (NPY) was associated with a 34 percent higher average alcohol consumption among the non-alcoholic population examined. Research published in the October issue of Alcoholism: Clinical & Experimental Research investigates if the Leu(7)/Pro(7) genetic polymorphism of NPY is associated with an increased susceptibility to alcoholism.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 796 - Posted: 10.20.2001

By STEVE LOHR THINK of it as computing's crisis of complexity, revisited. For more than three decades, the big advances in computing have soon brought new headaches. The initial steps ahead are typically in hardware - processors, storage and networks - and the headaches are manifested in software. It is software that is the medium for doing all the new things in computing that hardware makes possible - whether simple numeric calculations or increasingly sophisticated functions like symbolic processing, graphics, simulations, artificial intelligence and so on. In computing, opportunity breeds complexity. And complexity begets systems that can be buggy, unreliable and difficult to manage. ..... Mr. Horn's paper is intended partly as a call to action for researchers and the industry, but it also points toward a path for solving the problem. He calls it "autonomic computing." It is a biological metaphor suggesting a systemic approach to attaining a higher level of automation in computing. Just as a person's autonomic nervous system automatically handles all kinds basic functions - the heart rate, breathing and digestion, for example - in response to changing conditions, so, too, should computer systems, according to Mr. Horn. The human body "does all this without any conscious recognition or effort on your part," he writes. "This allows you to think about what you want to do and not how you'll do it: you can make a mad dash for the train without having to calculate how much faster to breathe and pump your heart." Copyright 2001 The New York Times Company

Keyword: Robotics
Link ID: 789 - Posted: 10.20.2001

IN THE FIRST STUDY TO SHOW THAT A NON-HUMAN, NON-APE ANIMAL SHARES A CENTRAL ASPECT OF HUMAN INTELLIGENCE Two baboons successfully used analogous thinking to match symbol arrays that were the "same but different" WASHINGTON - More non-human animals may be capable of abstract thought than previously known, with profound implications for the evolution of human intelligence and the stuff that separates homo sapiens from other animals. A trans-Atlantic team of psychologists has found evidence of abstract thought in baboons, significant because baboons are "old world monkeys," part of a different primate "super family" that -- some 30 million years ago -- split from the family that gave rise to apes and then humans. Chimpanzees, in the ape family, already have demonstrated abstract thought. Now, two trained baboons successfully determined that two differently detailed displays were fundamentally the same in their overall design. Figuring this out required analogical (this is to this as that is to that) reasoning, which many theorists view as the foundation of human reasoning and intelligence.

Keyword: Evolution; Animal Communication
Link ID: 788 - Posted: 10.20.2001

Controversial practice updated as treatment for severe depression by Nick Perry Journal Reporter John's face flinches as steel paddles press against his right temple and dampened forehead. An electrical pulse is jolting his brain into seizure. A mouthguard keeps him from grinding his teeth. His face slackens four seconds later when Dr. Patrick Mathiasen pulls the paddles away. Muscle-relaxing drugs and a general anesthetic keep John almost motionless. Only his right calf can move. It twitches below a tourniquet, which keeps blood carrying the drugs from reaching his calf. Mathiasen touches the twitching leg and counts off the seconds. All materials Copyright © 2001 Horvitz Newspapers, Inc.

Keyword: Depression
Link ID: 783 - Posted: 10.20.2001

The most common drugs used today to treat depression focus their attention on the brain chemicals, serotonin and norepinephrine. Increasing evidence, however, now indicates that another player in the brain, corticotropin-releasing factor, should share the spolight. Studies have shown that abnormally high activity of this stress hormone is present in many cases of depression. Furthermore, research shows that drugs that block the action of corticotropin-releasing factor have the potential to lift the dismally low spirits of the depressed. The new insights help explain how depression arises and may lead to new options for prevention and treatment. Depression, with its feelings of intense sadness, worthlessness, pessimism and reduced emotional well-being, afflicts more than 18 million Americans. On a cheerier note, drug therapies can help some sufferers regain a zest for life. The drugs most commonly used today to treat the illness target the brain chemicals, serotonin and norepinephrine. Increasing evidence now indicates that targeting another player in the brain, corticotropin-releasing factor (CRF), also may aid people. Copyright © 2001 Society for Neuroscience. All rights reserved.

Keyword: Depression; Hormones & Behavior
Link ID: 782 - Posted: 10.20.2001