By JANE E. BRODY Paula Schneider was 38 when she developed what doctors first thought was carpal tunnel syndrome. But soon the trouble she had moving her right arm spread to her neck and back and then the whole body. She lost control of her limbs, head and torso, leaving her unable to walk, sit, eat or do much of anything. It was as if her entire body had been inhabited by jitterbugs that determined her every move. More Personal Health Columns "I couldn't eat like a normal person, brush my teeth or drink from a glass because it would break when I tried to put it down," Ms. Schneider recalled recently at a demonstration on movement disorders at Beth Israel Hospital in New York. The cause, she eventually learned, was a severe movement disorder called generalized dystonia. Various medications helped for a while. So did multiple localized injections of Botox to disrupt the flow of nerve impulses to muscles that were spastic or excessively contracted. But the benefits were limited and short-lived. She said she spent 12 years in excruciating pain. Copyright 2005 The New York Times Company

Keyword: Movement Disorders
Link ID: 8134 - Posted: 11.08.2005

By CARL ZIMMER In a laboratory at Indiana State University, a dozen green iguanas sprawl tranquilly in terrariums. They while away the hours basking under their heat lamps, and at night they close both eyes - or sometimes just one. They lead comfortable lives pretty much indistinguishable from any ordinary pet iguana, except for one notable exception: the bundles of brain-wave recording wires that trail from their heads. A team of scientists at Indiana State would like to know what happens in the brains of the iguanas when the lights go out. Do they sleep as we do? Do they shut the whole brain down, for example, or can they keep one half awake? These scientists in Terre Haute hope the iguanas will also help shed some light on an even more fundamental question: why sleep even exists. "Sleep has attracted a tremendous amount of attention in science, but we really don't know what sleep is," said Steven Lima, a biologist at Indiana State. Dr. Lima belongs to a small but growing group of scientists who are pushing sleep research deep into the animal kingdom. They suspect that most animal species need to sleep, suggesting that human slumber has an evolutionary history reaching back over half a billion years. Copyright 2005 The New York Times Company

Keyword: Sleep
Link ID: 8133 - Posted: 11.08.2005

STANFORD, Calif. - Need more evidence that men and women are different? Look no further than the Sunday funnies. According to a new Stanford University School of Medicine study, gender affects the way a person's brain responds to humor. The first-of-its-kind imaging study showed that women activate the parts of the brain involved in language processing and working memory more than men when viewing funny cartoons. Women were also more likely to activate with greater intensity the part of the brain that generates rewarding feelings in response to new experiences. "The results help explain previous findings suggesting women and men differ in how humor is used and appreciated," said Allan Reiss, MD, the Howard C. Robbins Professor of Psychiatry and Behavioral Sciences and director of the Center for Interdisciplinary Brain Sciences Research. He added that the results, which appear in the Nov. 7 online issue of the Proceedings of the National Academy of Sciences, could lead to a better understanding of medical conditions such as depression and cataplexy. Researchers know that a number of brain structures, including the prefrontal cortex, which is involved in language processing and memory, are involved in humor appreciation. In 2003, Reiss and colleagues showed for the first time that the brain's mesolimbic reward center, which is responsible for the rewarding feelings that follow such events as monetary gain or cocaine use, is also activated by humor.

Keyword: Sexual Behavior; Brain imaging
Link ID: 8132 - Posted: 11.08.2005

During our waking hours, our brains are inundated with sensory information that shifts from one moment to the next. Recognizing meaningful associations between different snippets of this information is a basic form of learning that is essential for survival, even for animals with much simpler brains than our own. For learning to occur, these associations must be made and reinforced in some way at the neuronal level, but how this happens is poorly understood. Research reported this week sheds light on this problem by identifying a group of neurons whose activity changes during the learning process in a way that reflects the new association that is formed between two different sensory stimuli. The findings are reported in Current Biology by André Fiala and colleagues at Bayerische Julius-Maximilians-Universität Würzburg, Germany. To address the question of how the relevance of a stimulus is represented at the level of neuronal cells, the researchers used the fruit fly Drosophila as a model organism. These tiny animals can be trained to associate an otherwise neutral odor stimulus with a negative experience, such as a small electric shock, and ultimately learn to avoid this odor. Using sensitive imaging methods, the researchers observed the activity of certain neurons within the fly's brain during such training. They found that prior to training, these cells, which release the neurotransmitter dopamine, become especially activated if the negative stimulus--the small shock--occurs, but show only a weak activity in response to odors.

Keyword: Learning & Memory
Link ID: 8131 - Posted: 11.08.2005

We humans are creatures of habit, whether they're good… "I've been trying to do a regular exercise habit, but it's been on and off," says Erwin Lara from New Jersey. … or not so good. "If I have a cigarette in my hand I need a coffee in my other hand and if I have a coffee in one hand I need a cigarette in my other hand," admits New Yorker Robert Noriega. We all know habits are hard to kick, but what's actually going on inside our brains? Massachusetts Institute of Technology neuroscientist Ann Graybiel thinks she knows, and she may be able to explain why many of us fall back into bad habits even after years of being good. "We all hear stories of smokers who try so hard to quit smoking cigarettes and they finally quit," she says. " They haven't smoked in years, and then one day, they're in that very situation where they used to smoke, and a flood of who knows what, memory or something, triggers off the pattern and all of a sudden the habit is back." © ScienCentral, 2000-2005.

Keyword: Drug Abuse
Link ID: 8130 - Posted: 06.24.2010

Certain behaviors, such as eating, drinking and urinating, are so crucial to survival that the brains of all vertebrates contain clusters of nerve cells that can suppress pain long enough to allow the animal to eat, drink -- or pee -- in peace. A report from researchers at the University of Chicago, published early online in the Proceedings of the National Academy of Sciences, shows that by activating "OFF" cells and shutting down "ON" cells in the ventromedial medulla (VMM) – a small region in the brain stem – animals provide themselves with a form of "eating-induced analgesia," allowing them to complete essential tasks even in a difficult situation. "Escaping pain and potential dangers may be important protective behaviors, but eating, drinking, and eliminating wastes are absolutely essential," said study author Peggy Mason, Ph.D., professor in the department of neurobiology, pharmacology and physiology (NPP) at the University of Chicago. "What we found was a very effective system that lets these animals focus on the essentials and postpone concerns that are slightly less pressing. It's as if they could give themselves a six-second dose of morphine, allowing hunger to override pain."

Keyword: Pain & Touch
Link ID: 8129 - Posted: 06.24.2010

(Philadelphia, PA) - Researchers may have discovered a new way that may ultimately assist in the early diagnosis of schizophrenia - by utilizing MRI to study the patient's brain. Researchers at the University of Pennsylvania Health System (UPHS) looked for subtle brain abnormalities that cannot be seen by the human eye. A study examined the entire brain, looking at distributed patterns of abnormalities rather than differences in specific regions of the brain. "In this study, we used high-dimensional shape transformations in which we compared a brain image with a template of a normal brain. Through this comparison, we then determined where and how the patient's brain differed from healthy controls," explained Christos Davatzikos, PhD, Director of the Section of Biomedical Image Analysis in the Department of Radiology at Penn. "These methods are able to identify abnormalities that could not be detected by human inspection of the images created via MRI And, up until now, structural MRI has typically been used to diagnose physical anomalies like stroke or tumors, but it has not been helpful for diagnosis of psychiatric diseases." Davatzikos says, "MRI produces images which are traditionally read mostly by radiologists. Now, we can do a quantitative reading of these images - bringing out information that is not obvious to the eye; one can think of computer readings as computational scanners. It's a second level that says 'analyze this image and produce another image that highlights subtle abnormalities in the brain.'

Keyword: Schizophrenia; Brain imaging
Link ID: 8128 - Posted: 11.08.2005

Roxanne Khamsi Can depression be explained by a simple chemical imbalance in the brain? A pair of researchers has complained that the evidence for this is weak, and that drug companies should not be allowed to push this message in their advertisements. After being bombarded by messages that depression is caused by the lack of a certain chemical in the brain, say the researchers, patients may be sceptical of other kinds of treatment, including other drugs and talking to a therapist. "That message [in the advertisements] is at odds with what's in the scientific literature," says Jonathan Leo of the Lake Erie College of Osteopathic Medicine in Bradenton, Florida, who co-authors an essay on the subject in PLoS Medicine this week1. The duo would like the Food and Drug Administration (FDA), which regulates drug advertising in the United States, to take a look at antidepressant ads and issue warnings to any firm that does not comply with its rules. At issue are a class of antidepressant drugs called selective serotonin reuptake inhibitors (SSRIs). The class includes such blockbusters as Prozac (fluoxetine), Zoloft (sertraline) and Paxil (paroxetine). ©2005 Nature Publishing Group

Keyword: Depression
Link ID: 8127 - Posted: 06.24.2010

A cure for one of the most common forms of learning disability may be on the horizon, US researchers have revealed. They reversed the condition in adult mice born with it, curing their learning disabilities by using a commonly prescribed drug. The researchers say the technique could potentially lead to treatments for other learning disabilities. Neurofibromatosis type I (NF1) is a condition caused by a single gene defect that affects more than 1 in 3000 people. The defect is either inherited or caused by a spontaneous mutation, which can then be inherited. NF1 causes developmental cognitive disabilities in up to half of those with the defective gene, including deficits in memory, motor coordination and spatial learning. It can also cause attention-deficit hyperactivity disorder (ADHD). Previous mouse studies show the cognitive deficits result from the mutant gene causing over-production of a molecule called p21Ras. This leads to an imbalance between the signals that activate brain cells and those that inhibit them, creating problems in the cell-to-cell communication needed for learning. Neurobiologist Alcino Silva and colleagues at the University of California, Los Angeles, US, tried a commonly prescribed cholesterol-lowering statin drug – called lovastatin – on adult mice with the NF1 mutation. In a series of experiments to test their cognitive functions, the team showed that the drug reversed the learning disabilities and brought the cognitive functions of the mice up to normal levels. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory
Link ID: 8126 - Posted: 06.24.2010

The female hormone oestrogen could give women the edge when it comes to tasks such as safe driving, say researchers. Tests showed attention span and ability to learn rules were far better among women than men. The Bradford University scientists told a hormone conference in London how tasks requiring mental flexibility favour women over men. A woman's oestrogen levels may prime the part of the brain involved in such skills - the frontal lobe - they said. They asked 43 men and women aged 18-35 to perform a battery of neuropsychological tests that assessed skills such as spatial recognition memory, rule learning, attention, planning and motor control. The women were far better at being able to shift their attention from one stimulus to another, making it easier for them to perform everyday actions like driving and reading. This might explain why girls find it easier than boys to concentrate at school and why women are more careful drivers, the researchers hypothesise. Speaking at the Society for Endocrinology meeting, they said: "This study demonstrates that tasks requiring mental flexibility favour women over men, an area previously not considered to elicit strong sex differences. Driving could be an example of how this is applied to everyday life. "Our study suggests that oestrogens may positively influence neuronal activity in the frontal lobes, the area of the brain stimulated by tasks of attention and rule learning, which could explain the female advantage when performing these tasks." (C)BBC

Keyword: Hormones & Behavior; Attention
Link ID: 8125 - Posted: 11.07.2005

By JAMIE SHREEVE FOR a span of some dozen years early in his career, Robert M. Sapolsky, a neurologist and primatologist at Stanford University, spent three or four months a year conducting field research on baboons in Kenya. Over time, he developed an intimate appreciation of the nuances in behavior common to these highly social primates and ourselves. But it was lonely work, and Sapolsky found himself writing scads of letters back home, simply in hopes of getting some mail in return. Thus was forged a zeal for writing in a person with no literary pretension but a great deal to write about. While in two of his previous books for a popular audience, Sapolsky focuses on his own research on the neurobiology of stress ("Why Zebras Don't Get Ulcers") and his life as a scientist ("A Primate's Memoir"), "Monkeyluv," a collection of essays published over the last 10 years in Discover, Natural History, The New Yorker and other magazines, casts a wider net. For the most part, the essays represent what Sapolsky himself describes as "hit-and-run obsessions" - topics that infect his mind for a couple of months, causing him to research endlessly and drive his poor wife to distraction with monologues on the subject until he eventually writes the obsession out of his system, leaving room for the next one. The result of this strategy is mostly a hit. The collection is organized into three sections, each hinging on some Big Question in natural science: the relative influence of genes and environment in determining behavior; how our brains affect our bodies and vice versa; and the way society shapes the individual. Like any good modern biologist, Sapolsky, a MacArthur "genius" award winner, relies in his research on the analytical power of reductionism: the more one divides natural phenomena into their constituent parts, and those parts into subparts and so forth, the more one can learn about how nature really works. As the essays in the first section make clear, however, the notion that the genes at the base of this biological hierarchy determine the workings of everything above them is total nonsense. Copyright 2005 The New York Times Company

Keyword: Genes & Behavior; Evolution
Link ID: 8124 - Posted: 11.07.2005

A chemical compound in wine reduces levels of a harmful molecule linked to Alzheimer's disease. In a recent study, resveratrol--one of several antioxidants found in wine--helped human cells break down the molecule, which contributes to the lesions found in the brains of Alzheimer's patients. Fortunately for teetotalers, the compound is also found elsewhere. "Resveratrol is a natural polyphenol occurring in abundance in several plants, including grapes, berries and peanuts," says author Philippe Marambaud of the Litwin-Zucker Research Center for the Study of Alzheimer's Disease and Memory Disorders in Manhasset, New York. "The polyphenol is found in high concentrations in red wines." The scientists found that 40 micromoles (a measure of the amount of resveratrol in a liter of solution) cut levels of the molecules--amyloid-beta peptides--by more than half. Treatment with proteasome-inhibitors nullified the benefit. The team therefore thinks the substance works by boosting the ability of the proteasome--a multi-protein complex that breaks down other proteins inside a cell. These findings will be published in the November 11 issue of the Journal of Biological Chemistry. © 1996-2005 Scientific American, Inc.

Keyword: Alzheimers
Link ID: 8123 - Posted: 06.24.2010

WASHINGTON -- Two studies in the October issue of Behavioral Neuroscience show that when animals are stressed, deprived and exposed to tempting food, they overeat, with different degrees of interaction. The powerful interplay between internal and external factors helps explain why dieters rebound and even one cookie can trigger a binge if someone's predisposed to binge. The findings also implicate the brain's opioid, or reward, system in regulating overeating, especially when the food is extra-tempting – and not only in under-fed animals. This knowledge may help even non-stressed people to avoid overeating, keep their weight down and improve their health. Behavioral Neuroscience is published by the American Psychological Association (APA). A study by M. Flavia Barbano, PhD, and Martine Cador, PhD, at the University of Bordeaux 2 in France, separated the distinct roles in consumption played by food deprivation and the "yum" factor, establishing that the interplay between internal and external factors regulates food intake, at least in mammals. Although much has been learned about human overeating, it is easier to untangle and verify the different variables involved in controlled animal studies. Working with laboratory rats, the researchers tested three aspects of eating behavior: motivation (how bad did they want it), anticipation (how excited were they in advance), and intake (how much did they eat), all relative to homeostasis (satiety or deprivation) and food type (ordinary lab chow or "highly palatable" chocolate breakfast cereal, as verified by a pre-test of different foods).

Keyword: Obesity; Stress
Link ID: 8122 - Posted: 06.24.2010

Perceiving a simple touch may depend as much on memory, attention, and expectation as on the stimulus itself, according to new research from Howard Hughes Medical Institute (HHMI) international research scholar Ranulfo Romo and his colleague Victor de Lafuente. The scientists found that monkeys' perceptions of touch match brain activity in the frontal lobe, an area that assimilates many types of neural information. Romo and de Lafuente, both of the Institute of Cellular Physiology at the National Autonomous University of Mexico, report their results in the December 2005 issue of the journal Nature Neuroscience, published early online on November 6, 2005. One of neuroscience's most difficult questions concerns how the brain converts simple sensory inputs to complete perceptual experiences. Many neuroscientists assume that perceptions arise in the sensory cortices, which are the first areas of the brain to process information coming in from sense organs, Romo said. Some recent research, however, has hinted that activity in other parts of the brain may also contribute to sensory perception. When it comes to the sense of touch, a stimulus at the skin triggers an impulse that travels first to an area at the top of the brain called the primary somatosensory cortex (S1). The information then moves to other parts of the brain, where it can contribute to memory, decision-making, and motor outputs. © 2005 Howard Hughes Medical Institute.

Keyword: Pain & Touch
Link ID: 8121 - Posted: 06.24.2010

A substance made by immune cells may play a key role in the development of multiple sclerosis, research suggests. A team at Ohio State University found the molecule blocked progression of a similar disease in mice. The findings suggest blocking the molecule - macrophage migration inhibitory factor (MIF) - might be an effective way to treat MS. The Journal of Immunology study also suggests testing for MIF may help predict flare-ups of illness. The Ohio State team worked on mice bred to develop a disease which closely resembles MS. They found animals with MIF developed the initial, acute phase of the disease, but then showed no signs of further progression. Lead researcher Professor Caroline Whitacre said: "Our results suggest that MIF may be less important for initiating MS, but that it may be necessary for MS progression. These findings indicate that in the future we can perhaps use MIF levels to predict the onset of a relapse. But more importantly, perhaps this study will lead to drugs that can halt the course of MS by blocking the action of MIF." MS is an autoimmune disease caused by the immune system turning in on itself and attacking the body's own tissues. In MS, immune cells destroy the myelin sheath that surrounds nerve fibres in the brain and spinal cord and enables them to transmit impulses. (C)BBC

Keyword: Multiple Sclerosis
Link ID: 8120 - Posted: 11.05.2005

By NED MARTEL The PBS series "Nature" enlivens the screen with colorful, robust animal behavior, but its undertones are also mournful, longing for lost links between society and ecology. In the Sunday premiere of its 24th season, cooperation between man and beast is recalled through the story of how an Australian whale killer and a killer whale together harvested enormous humpbacks. The bloody teamwork took place in a far-off idyllic cove off the southeast coast of Australia in the early part of the 20th century. George Davidson led wooden rowboats into rough waters, churning with the chaos of sleek orcas corralling longer, less nimble humpback whales. The valiant Mr. Davidson harpooned the bigger beasts by hand, and the reward for the cooperative killer whales was a chance to attack the carcasses and pull out their tongues, which to them are some sort of delicacy. To each his own, apparently, in this mammalian collaboration, and Mr. Davidson and his orca partner, named Old Tom by the cove's residents, have become legendary. "He'd work them 'round like the way a hound dog would round up the sheep," says Bill Blaxter, 92, who saw the beast through a boy's eyes. The end of the productive alliance between Mr. Davidson and Old Tom was not so happy and not really their fault. Faster, more mechanized whaling procedures in the deeper waters reduced the humpback population in short order. Then, less respectful landlubbers took action that made the killer whales doubt that they could trust the two-legged types, after all. Copyright 2005 The New York Times Company

Keyword: Miscellaneous
Link ID: 8119 - Posted: 11.05.2005

Researchers have reduced Alzheimer's symptoms in mice by deleting a single gene in the brain. The findings may allow the development of therapies that are safer and more selective for preventing and treating the disease. Alzheimer's disease is associated with inflammation and plaque build-up in the brain. Research suggests that nonsteroidal anti-inflammatories (NSAIDs) such as ibuprofen and naproxen can help prevent symptoms in people by inhibiting the cyclooxygenase pathway, which promotes inflammation. The drugs work by blocking two of the pathway's enzymes, COX-1 and COX-2. Unfortunately, the COX enzymes also help maintain stomach lining, and blocking COX-1 throughout the body can lead to gastric ulcers and intestinal bleeding, while blocking COX-2 may cause stroke. So Katrin Andreasson, a neurologist at Johns Hopkins University in Baltimore, Maryland, and colleagues started looking for a part of the cyclooxygenase pathway that acts specifically on the brain. Earlier work had shown that one component of the pathway called PGE2 binds to a brain receptor known as EP2. © 2005 by the American Association for the Advancement of Science.

Keyword: Alzheimers
Link ID: 8118 - Posted: 06.24.2010

Ben Harder Male mice may serenade prospective mates at pitches about two octaves higher than the shrillest sounds audible to people. This "mouse song" is comparable in complexity to the sequences of tones that songbirds and some whales make, say Timothy E. Holy and Zhongsheng Guo of Washington University in St. Louis. Other researchers remain guarded about labeling mouse vocalizations as song. Nevertheless, says neurophysiologist Xiaoqin Wang of Johns Hopkins University School of Medicine in Baltimore, the discovery that mice emit richly patterned ultrasonic noises could have important implications for the study of communication. Scientists have known that mice produce ultrasound. When pups become isolated from their mothers, for example, they utter high-pitched cries that launch a maternal search-and-rescue operation. Adult males also vocalize when they detect female odors. To investigate whether the adults make distinct syllables expressed in specific sequences, Holy and Guo recorded vocalizations by 45 male mice. The researchers placed the mice, one at a time, in a microphone-equipped chamber and inserted a urine-soaked cotton swab through a hole in one wall. Copyright ©2005 Science Service

Keyword: Sexual Behavior; Hearing
Link ID: 8117 - Posted: 06.24.2010

The brain structure of people with autism is an "exaggeration" of the normal male brain, researchers suggest. It has long been suggested that autistic behaviour is an exaggeration of male habits such as making lists. But Cambridge Autism Research Centre researchers say the actual development of the autistic brain also exaggerates what happens in male brains. Writing in Science, they say investigating this theory further will aid understanding of autism. The team, led by Professor Simon Baron-Cohen, looked at research carried out into this "extreme male brain" explanation for autism. They point to evidence that males generally have greater early growth of certain brain regions, and less hemispheric connectivity than females. Boys' brains grow more quickly than girls'. In the brains of people with autism, this growth appears to occur to an even more extreme degree. There are also specific differences seen in certain areas of the brain. The amygdala, which plays a key role in emotional responses, is abnormally large in toddlers with autism; again an exaggeration of the typical development of the male brain. The researchers say evidence points to exposure to male hormones, such as testosterone, before birth affecting these brain development patterns. Male foetuses produce these hormones from their testes, and female foetuses from their adrenal glands. (C)BBC

Keyword: Autism; Sexual Behavior
Link ID: 8116 - Posted: 11.04.2005

By Marc Kaufman In an escalating dispute over how the government regulates powerful painkilling drugs, the Food and Drug Administration is seeking to prevent renewal of a provision that last year gave the Drug Enforcement Administration final say over allowing new narcotic medications on the market. The FDA's deputy commissioner for medical and scientific affairs, Scott Gottlieb, said yesterday that the agency opposed the legislation, which for the second year in a row was added by the House to the yearly appropriations bill for several major departments. "Specific language attached to the appropriations bill would ultimately delay access by physicians and their patients to important, safe and effective pain management and palliative care medicines," Gottlieb said. He said giving DEA authority over traditional FDA territory could upset "a delicate balance for managing both safety and access." Although the dispute is ostensibly over a limited change in how controlled drugs are approved and labeled, it has become something of a stand-in for a larger battle over whether DEA's actions are intruding into the practice of medicine and denying pain sufferers relief they need. © 2005 The Washington Post Company

Keyword: Pain & Touch; Drug Abuse
Link ID: 8115 - Posted: 06.24.2010