Duke University Medical Center researchers have discovered that neurons take in receptors and other molecules from their surface membranes through discrete "doorways" -- specialized domains on the surface of nerve cells that regulate such entry. The discovery of such entry points drastically revises a long-held theory that surface molecules such as receptors are enveloped right where they rest in the fatty membrane, to be drawn into the cell’s interior. This uptake process, called endocytosis, is part of the constant cycling of receptors to and from the membrane surface. The balance of this cycling is the principal means by which neurons regulate the number of surface receptors for such chemical triggers as neurotransmitters and drugs -- thereby controlling neuronal sensitivity to such external chemical triggers. The newly discovered "endocytic zones" are also entry points for nutrients and pathogens such as viruses. © 2002 Duke News Service

Keyword: Development of the Brain
Link ID: 2859 - Posted: 06.24.2010

Berkeley - Any wine connoisseur knows the nose can learn to recognize subtle new aromas, but where does that learning take place? A new study by a team of neuroscientists at the University of California, Berkeley, has determined that we learn new smells in an area of our brains, not just in our noses, which have neural receptors previously thought to be solely responsible for a person's ability to detect new odors. This finding has prompted the team, led by graduate student Joel Mainland and Noam Sobel, assistant professor of psychology, to conclude that the adult brain has more capabilities to change than previously thought. The study appears in the Oct. 24 issue of Nature.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 2858 - Posted: 10.24.2002

Rob Carson; The News Tribune The debate over whether homosexuals should be given legal protection from discrimination often gets hung up on one difficult question: What makes people homosexual? Is one born that way? Or is it a matter of choice? Many of those opposed to protection for gays and lesbians rely on the belief that homosexuals choose their lifestyle. Therefore, the argument goes, they deserve no special legal protection. © 2002 Tacoma News, Inc.

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 2857 - Posted: 06.24.2010

It really is contagious, say psychologists If you meet someone who looks angry or happy, it is often hard to remain expressionless yourself - and now scientists believe they know why. Researchers in Sweden believe your unconscious mind exerts direct control of your facial muscles. However much you struggle to keep a blank face, your brain may be letting you down. It is well known that emotions can find their way into your facial expression, body language, and gestures, but researchers at Uppsala University are trying to work out to what extent we are in control of these movements. Dr Ulf Dimberg told volunteers to react to a series of pictures of expressionless, happy or angry faces. They were told to make frowning, smiling or expressionless faces in return. (C) BBC

Keyword: Emotions
Link ID: 2856 - Posted: 10.23.2002

Tests reveal clear diversity in cognitive and brain measures,which may aid diagnosis and treatment strategies WASHINTON - Schizophrenia may not be one single disease but rather an array of disorders whose psychiatric and cognitive symptoms vary according to which part of the brain is affected and to what degree. That's the conclusion of a study published in the October issue of Neuropsychology, in which a seven-neuroscientist team linked schizophrenic subtypes with different memory problems and different brain anatomies. The scientists say this is a "first step in our efforts to uncover the specific biological mechanisms of the disorder," which they hope will lead to better diagnosis and treatment of people with schizophrenia. Neuropsychology is published by the American Psychological Association (APA). Bruce Turetsky, M.D., of the University of Pennsylvania Health System, led the study, which examined 116 patients diagnosed with schizophrenia and 129 normal control participants. The researchers used the California Verbal Learning Test to assess different aspects of learning and memory, including overall recall ability, rate of learning over repeated trials, ability to retain learned material over time, and subsequent item recognition. Using MRI and PET scan images, they also studied the brain anatomy and metabolism of participants.

Keyword: Schizophrenia
Link ID: 2855 - Posted: 10.23.2002

By GINA KOLATA When a large study of hormone replacement therapy was abruptly halted last summer because of risks from the drugs, scientists immediately began a reassessment of all other studies that involved the drugs. Now, one additional study has been halted, and participants in studies that are continuing have had to give their consent again. Researchers say the ripples from the hormone replacement study will spread for years, making them think carefully about when, if ever, to subject healthy women to estrogen therapy in scientific studies. "The Women's Health Initiative has given us an understanding of the risks," said Dr. Richard Hodes, the director of the National Institute on Aging, referring to the first study that was stopped. "We have to ask whether despite that knowledge, there is reason to continue a study." Copyright The New York Times Company

Keyword: Hormones & Behavior
Link ID: 2854 - Posted: 10.23.2002

Hormones have long been considered the solo act that molds brains along gender lines. But in recent years, hints that certain genes on the sex chromosomes might also play a role have been emerging. Now, new research points to the first structural brain difference between male and female mammals attributed to genetics alone. Sex hormones, in particular testosterone, help shape the developing brain of fetuses and newborns. Testosterone, secreted by the gonads, makes male brains distinct from female ones, and it is thought to account for difference in behavior and brain structure. A group of scientists, though, has wondered for years whether genes on the X and Y chromosomes have a hand in shaping brain differences. To find out, neuroendocrinologist Arthur Arnold at the University of California, Los Angeles, collaborated with colleagues in the United Kingdom who had genetically altered mice. Robin Lovell-Badge and Paul Burgoyne, developmental geneticists at the Medical Research Council’s National Institute for Medical Research in London, performed a genetic sex change. By using mice with a deletion in their Y chromosome for a gene called Sry, which kick-starts testes development, they ended up with XY “females” that had ovaries; adding Sry to the genomes of females generated XX "males" with testes. Although these mice had fully developed sex organs, both groups had fertility problems due to the gene manipulations. Copyright © 2002 by the American Association for the Advancement of Science.

Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 2853 - Posted: 06.24.2010

UCLA Neuropsychiatric Institute researchers have localized a region on chromosome 16 that is likely to contain a risk gene for Attention Deficit Hyperactivity Disorder, the most prevalent childhood-onset psychiatric disorder. Their research, published in the October edition of the American Journal of Human Genetics, suggests that the suspected risk gene may contribute as much as 30 percent of the underlying genetic cause of ADHD and may also be involved in a separate childhood onset disorder, autism. Pinpointing a gene with a major role in ADHD will help researchers and clinicians better understand the biology of this disorder and likely lead to the development of improved diagnosis, treatment and early intervention.

Keyword: ADHD; Autism
Link ID: 2852 - Posted: 10.23.2002

ANN ARBOR-Talking with friends helps keep the mind sharp, a University of Michigan study suggests. "As the population ages, interest has been growing about how to maintain healthy brains and minds," U-M psychologist Oscar Ybarra said. "Most advice for preserving and enhancing mental function emphasizes intellectual activities such as reading, doing crossword puzzles, and learning how to use a computer. But my research suggests that just getting together and chatting with friends and family may also be effective." In a series of studies with older and younger adults, Ybarra examined the degree to which social engagement predicted cognitive, or mental, function. In one study, he analyzed data on 3,617 Americans between the ages of 24 and 96, including measures of how often participants reported talking on the phone with friends, neighbors and relatives; how often they reported getting together with them; and how many people they identified with whom they could share their most private feelings and concerns.

Keyword: Language; Intelligence
Link ID: 2851 - Posted: 10.23.2002

Research shows link to reduced neurogenesis Associated Press NEW YORK - It was one of the most startling brain discoveries in recent history: the finding, announced in 1998, that people keep making new brain cells well into adulthood. Now, scientists are looking into another surprising idea, that waning and waxing of this brain cell birthing contributes to depression and the effects of antidepressants. If true, it could help unlock the riddle of what goes wrong in the brain to bring on the mood disease. And it could help lead to better treatments, such as faster-acting antidepressants. Copyright © 2002, The Baltimore Sun

Keyword: Depression; Neurogenesis
Link ID: 2850 - Posted: 06.24.2010

Increasing the amount of vitamin E in the diet may help reduce the risk of developing Parkinson's disease, research suggests. Previous studies have suggested that the degenerative brain disorder may in some way be linked to cell damage caused by oxidation, the process by which oxygen is converted into energy. Vitamins E and C and the carotenoids are known to help minimise this effect by mopping up free radicals, the particles released by oxidation which cause damage. Researchers from three US centres tested whether the use of these so-called anti-oxidants could have any positive impact on the development of Parkinson's. They could find no positive effect from taking dietary supplements, but their work does suggest that upping the amount of vitamin E in the diet may have some protective effect. (C) BBC

Keyword: Parkinsons
Link ID: 2849 - Posted: 10.22.2002

By LAURIE TARKAN No one has found a cure for autism, the neurological disorder that leads to lifelong impairments in a child's ability to speak, respond to others, share affection and learn. But there is a growing consensus that intensive early intervention is both effective and essential — the sooner after diagnosis, the better. Early intervention, which involves many hours of therapy with one or more specialists, does not help every autistic child to the same degree. It is best started no later than age 2 or 3, and for reasons that are unclear, it does not help some children at all. But for those who are helped, their parents say, the changes are miraculous. Yet the success of early intervention is posing a painful predicament for schools and families — a predicament made more immediate by a rising tide of diagnoses of autism. Last week, researchers reported that the number of austistic children in California had risen more than sixfold since 1987, and other states and the federal government have also noted sharp increases. Copyright The New York Times Company

Keyword: Autism
Link ID: 2848 - Posted: 06.24.2010

Copyright © 2002 AP Online By LAURAN NEERGAARD, AP Medical Writer WASHINGTON ( - As premature babies fight for life, another battle is raging behind their tiny eyelids - an eye disease that ultimately blinds up to 2,000 of these infants a year. Now scientists are exploring two promising new ways to save preemies' eyesight: strictly maintaining the babies' oxygen levels at a constant but slightly lower level than usual - which apparently slashed blindness at one major hospital - and giving the smallest babies an eye-important growth hormone they lack. Preventing the blinding disease - called retinopathy of prematurity, or ROP - is a major goal because once it hits there's no sure way to save vision. Today's best treatment, laser therapy, decreases the chance of blindness by only a quarter, and many babies who don't go blind still will never see well enough as adults to drive. Copyright © 2001 Nando Media

Keyword: Vision; Development of the Brain
Link ID: 2847 - Posted: 06.24.2010

WEST LAFAYETTE, Ind. – Dogs' quirky, unexplainable repetitive behaviors can be part of an anxiety condition known as canine compulsive disorder. Andrew Luescher, director of Purdue's Animal Behavior Clinic and one of about 30 board certified animal behaviorists in the country, estimates that 2 percent of the dog population has canine compulsive disorder. Dogs with the disease often display compulsive behaviors such as tail chasing, snapping the air, licking excessively, chewing with an empty mouth and barking monotonously without any change in volume or intonation. Luescher has seen animals with severe stereotypical behaviors that affect their daily living. For example, one dog stopped drinking water because its shadow was a distraction.

Keyword: Stress
Link ID: 2846 - Posted: 06.24.2010

Researchers at the National Institutes of Health have developed several drug candidates that show promise in animal studies in protecting the brain against sudden damage from stroke, with the potential for fighting chronic neurodegenerative conditions like Parkinson's and Alzheimer's disease. The drugs, called p53 inhibitors, attack a key protein involved in nerve cell death and represent a new strategy for preserving brain function following sudden injury or chronic disease, according to the researchers. Their findings will appear in the Nov. 7 print issue of the Journal of Medicinal Chemistry, a peer-reviewed publication of the American Chemical Society, the world's largest scientific society. "This is a completely new therapeutic strategy for Alzheimer's and other neurodegenerative diseases, which warrants further assessment to allow it to move to clinical trials," says Nigel H. Greig, Ph.D., a researcher with the National Institute on Aging's Intramural Research Program in Baltimore, Md., and chief investigator for the study. "If it works, it could provide a new treatment approach for a wide range of neurological diseases."

Keyword: Alzheimers; Parkinsons
Link ID: 2845 - Posted: 10.22.2002

COLUMBUS, Ohio – Researchers have developed a new way to use a decade-old imaging method to directly compare the brains of monkeys with those of humans. Their report appeared in the journal Science. The method uses functional Magnetic Resonance Imaging (fMRI) – a technique that measures blood volume and flow and blood-oxygen levels in the brain. It also provides an indirect measure of neuronal activity in different regions of the brain. Neurons need oxygen and glucose to work. Blood carries both substances, and both can cross the blood-brain barrier. When a particular region of the brain is activated, the blood flow to that area temporarily increases in order to supply the neurons with fresh oxygen and glucose.

Keyword: Brain imaging
Link ID: 2844 - Posted: 06.24.2010

(CBS) A surgical experiment to see if shunts implanted in the brain are safe for treating Alzheimer's disease has researchers excited about the results. As CBS News Correspondent Elizabeth Kaledin reports, not only are they safe, it seems, but in 12 patients tested, they were successful in slowing progression of a disease robbing millions of Americans of their golden years. Dr. Gerald Silverberg, a neurosurgeon, says, "We saw improvement or stabilization in three months in the treated group as compared to the control group." ©MMII, CBS Worldwide Inc, All Rights Reserved

Keyword: Alzheimers
Link ID: 2843 - Posted: 06.24.2010

UCSF researchers identify infection prior to symptoms David Perlman, Chronicle Science Editor Scientists at UCSF are reporting today they have developed a highly sensitive test to detect the infectious proteins that have caused mad cow disease in Europe and other deadly disorders that afflict sheep, deer and elk in both Europe and America. By identifying infected cattle even before they show symptoms of the degenerative disorder, the test should also help prevent transmission of the disease-causing proteins to humans, said Dr. Jiri Safar, the lead author of the report. The lack of a fast, effective test hampered efforts to stem the mad cow epidemic in Europe during the 1980s and '90s, when 120 people died from eating infected beef and hundreds of thousands of cattle were destroyed out of concern that they were carriers of the disease. ©2002 San Francisco Chronicle.

Keyword: Prions
Link ID: 2842 - Posted: 06.24.2010

Scientists have used stem cells to treat brain cancer in mice. Not only did the treatment extend the animals' survival, it also appeared to wipe out the cancer completely in almost one in three cases. The researchers, from the Cedars-Sinai Medical Center in Los Angeles, took immature neural (nerve) cells from the bone marrow and used gene therapy to stimulate them to produce a cancer-killing protein. he cells were then injected into mice with brain tumours. Currently, the standard treatment for brain tumours is surgery, However, some tumours recur because cells have migrated away from the main site, and cannot be found. The researchers were particularly keen to target these migratory cells. (C) BBC

Keyword: Stem Cells
Link ID: 2841 - Posted: 10.21.2002

NewScientist.com news service The sudden and uncontrollable paedophilia exhibited by a 40-year-old man was caused by an egg-sized brain tumour, his doctors have told a scientific conference. And once the tumour had been removed, his sex-obsession disappeared. The cancer was located in the right lobe of the orbifrontal cortex, which is known to be tied to judgment, impulse control and social behaviour. But neurologists Russell Swerdlow and Jeffrey Burns, of the University of Virginia at Charlottesville, believe it is the first reported case linking damage to the region with paedophilia. "We're dealing with the neurology of morality here," says Swerdlow. Since the area does not affect physical health, "it's one of those areas where you could have a lot of damage and a doctor would never suspect something's wrong," he says. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior
Link ID: 2840 - Posted: 06.24.2010