By LEE BOWMAN, Scripps Howard News Service - You're at a crowded, noisy holiday party, trying to tune into the conversation of someone standing right next to you, but he or she might as well be speaking another language. Don't blame your hearing, or even the champagne. Researchers at the University of Florida in Gainesville have found that background noises don't just cover up conversation; they may actually scramble language-processing activity in the brain. Their experiments with rats are beginning to unravel why even perfectly loud speech may be hard to understand in a noisy room, a finding that has applications for everything from hearing aids to MP3 players. "Some people have a tremendously difficult time understanding speech in a noisy environment, and we've all had the experience of having someone tell us something, but we can't tell what it is that they are saying," said Purvis Bedenbaugh, an assistant professor of neuroscience at the university's medical college and the person who led the studies. "This research is the first step toward looking at why that would be." Their research was published earlier this year in The Proceedings of the National Academy of Sciences. The scientists examined how brain cells in alert rats responded to specific sounds while one of three standardized noises played in the background. Implanted electrodes recorded the activity in the auditory thalamus of the rats.

Keyword: Hearing
Link ID: 6637 - Posted: 12.31.2004

By BENEDICT CAREY Desperate parents of autistic children have tried almost everything - hormone injections, exotic diets, faith healing - in the hope of finding a cure. But more than 60 years after it was first identified, autism remains mystifying and stubbornly difficult to treat. About the only thing parents, doctors and policy makers agree on is that the best chance for autistic children to develop social and language skills is to enroll them in some type of intensive behavioral therapy. A government-appointed panel has endorsed such therapies, which can cost $40,000 to more than $60,000 per year. Parents fight to get their children placed in behavioral programs, encouraged by the claims of some therapists that they can produce astonishing improvement in up to 50 percent of cases. An estimated 141,000 children with autism receive special education services, in many cases including behavioral therapies, through public schools. Yet the science behind behavioral treatments is modest at best. Researchers have published very few rigorously controlled studies of the therapies, and the results of those studies have been mixed. While some children thrive, even joining regular classrooms, the studies have found that most show moderate or little improvement. And researchers say most parents now experiment with so many alternative treatments - including vitamins, diets, sensory therapies and computer games - that they muddy the results of behavior treatment, making it very hard to say what is causing a child to gain skills or to decline. Copyright 2004 The New York Times Company

Keyword: Autism
Link ID: 6636 - Posted: 12.30.2004

Could a drunk Drosophila (aka a fruit fly) lead scientists find a new way to treat alcoholism in people? Since we share about two-thirds of our genes with fruit flies, researchers hope to discover genetic pathways that control our brains' response to alcohol by measuring flies' sensitivity to intoxication. "In humans, the relationship between sensitivity and alcoholism is such that the less sensitive you are to alcohol, the more likely you are to become an alcoholic later in life," says Ulrike Heberlein, professor of anatomy at the University of California, San Francisco. Heberlein has shown in previous research that behavior-wise, drunk flies have a lot in common with drunk humans—more active at first, then poor coordination, then sluggishness, and eventually, passing out. She and her colleagues use a device they call an "inebriometer," in which flies are placed at the top of a four-foot high column and exposed to ethanol vapor. "When flies become intoxicated they lose their posture and they fall through the column and we measure how long it takes for the flies to come out of the column," says Heberlein. The researchers set out to find which regions in the flies' brains regulate sensitivity to alcohol intoxication. "We did this in an unbiased way by going into the fly brain using genetic tools and inactivating one brain region at a time," Heberlein explains. "And then we asked what happens to the behavior of the fly in the inebriometer." © ScienCentral, 2000- 2004.

Keyword: Drug Abuse
Link ID: 6635 - Posted: 06.24.2010

Memory slipping, Thelma Walton strains to read, something she had no trouble with five years ago. Her husband, Jim, prompts her every morning with simple math equations and writing tasks, constantly repeating patterns laid in her brain long ago. Now hard at this work, the promise of retirement and a leisurely everyman's every day is no longer theirs to enjoy. For Thelma and Jim, her Alzheimer's disease is fresh at every waking. "It's a frustrating disease," says Jim, a seventy-something retiree living in Raleigh, North Carolina. "You see a whole body and you expect that whole body to perform like it always did and it's not going to do that. The mind's not going to function that way." Slowly, as Alzheimer's creeps through the brain, it's likely to first affect something we take for granted: our library of smells. "Identifying smells involves not only perceiving the smell but comparing against your bank of smells in the brain," explains D.P. Devanand, a memory disorder researcher and co-director of the Memory Disorders Center at the New York State Psychiatric Institute. "People lose their memories for the smells that they had all their lives." Now, Devanand and a team of researchers have developed a simple scratch and sniff smell test aimed at detecting Alzheimer's early on, when olfactory memory wanes as a small brain area beneath the medial temporal lobe—it directs smell—starts accumulating tangles of stringy protein strands. © ScienCentral, 2000- 2004

Keyword: Alzheimers; Chemical Senses (Smell & Taste)
Link ID: 6634 - Posted: 06.24.2010

St. Louis, -- A recently developed mouse model of brain tumors common in the genetic disorder neurofibromatosis 1 (NF1) successfully mimics the human condition and provides unique insight into tumor development, diagnosis and treatment, according to researchers at Washington University School of Medicine in St. Louis. After validating their animal model, the team made two important discoveries: New blood vessels and immune system cells may be essential to the initial formation of tumors and therefore may be promising drug targets; and brain images often used to determine the need for treatment may not actually be diagnostically informative. "These mice develop brain tumors with many of the same features as those seen in children with NF1, and studying those tumors has helped us understand the cellular events involved in NF1 brain tumor development," says principal investigator David H. Gutmann, M.D., Ph.D., the Donald O. Schnuck Family Professor of Neurology. The study appears online and will be published in the January 2005 issue of the journal Annals of Neurology. NF1 is one of the most common neurological disorders caused by a single gene mutation. The disorder can lead to a variety of complications including brain cancer. To supplement their clinical research, Gutmann's team developed a mouse model in which the animals, like humans with the disease, have one abnormal copy of the gene for NF1 in every cell in their body, while specific support cells in the brain called astrocytes have two abnormal copies of this same gene.

Keyword: Genes & Behavior
Link ID: 6633 - Posted: 12.30.2004

St. Paul, Minn. – Longer and more intense physical activity may help people maintain their cognitive skills as they age, according to a 10-year study of elderly men published in the December 28, 2004 issue of Neurology, the scientific journal of the American Academy of Neurology. The study reviewed the data of 295 men, born between 1900 and 1920, from the Finland, Italy and Netherlands Elderly (FINE) Study. Beginning in 1990, researchers measured the duration and intensity of physical activities such as walking, bicycling, gardening, farming, sports, odd jobs, and hobbies. Cognitive functioning was tested with the Mini Mental State Examination. The study showed that over 10 years the cognitive decline in men who had reduced their daily physical activity by an hour or more was 2.6 times greater than the decline in men who maintained their activity. Men who performed their daily physical activity with a lower intensity 10 years later had a 3.6 times stronger decline than men who maintained the intensity level. Men who engaged in activities of the lowest intensity had up to 3.5 times greater decline than men who participated in activities with a higher intensity. There was no decline among those who increased the duration or intensity of their activities.

Keyword: Alzheimers
Link ID: 6632 - Posted: 06.24.2010

By THE ASSOCIATED PRESS WASHINGTON, (AP) - The government approved on Tuesday a drug that offers a new way of fighting severe pain, an option for patients who no longer benefit from morphine and other traditional pain medications. The drug, made by the Elan Corporation, is the first in a new class of drugs that selectively blocks the nerve channels responsible for transmitting pain signals. It will be marketed as Prialt and should be available by the end of January. "When you've taken all the kinds of pain medication that there is and you still have pain, that is a very frightening situation," said Dr. Lars Ekman, president of research and development for Elan, which is based in Dublin. "When you have that kind of pain, there is nowhere to go." The drug is part of a new class known as N-type calcium channel blockers. It is known chemically as ziconotide. Copyright 2004 The New York Times Company

Keyword: Pain & Touch
Link ID: 6631 - Posted: 12.29.2004

By JOHN O'NEIL Six years ago, my son James fell down a well, and he's still climbing out. James has autism. He is one of 150,000 or more American children classified in the last decade as having the once-rare disorder, including 25,000 in 2003. Half a century ago, polio epidemics left perhaps 5,000 children a year with some degree of disability, and the sight of children stricken overnight galvanized the nation. But autism's arrival, and the response to it, has not been so dramatic. In James's case, a bubbling 2-year-old who loved "mashed totatoes" and sword-fighting faded away. In his place was a nearly silent, unhappy child who repeated meaningless phrases, lay on the floor squinting or pulled cowboy boots on and off until his feet were raw. Every day he fell a little further out of the world. But one recent afternoon James sat at our kitchen table with his best friend, Larry, goofing off instead of doing homework. They made dumb jokes and gossiped about their "girlfriends" at their school, just up the street. It's hard for me to explain how many dreams-come-true are reflected in that one sentence. James's journey is by no means over. He still has significant problems with reading comprehension, math, attention and social skills. He gets stuck on favorite subjects - though this year, the Yankees, thankfully, replaced the War of 1812. He can sound as if he is speaking a second language, with the halts and mangling of idioms that implies. With his peers, he hovers at the border of acceptance. Copyright 2004 The New York Times Company

Keyword: Autism
Link ID: 6630 - Posted: 12.29.2004

Carl T. Hall, Chronicle Science Writer Revelations in the steroid scandal engulfing Major League Baseball have raised new questions about the medical effects of performance-enhancing drugs. Despite the well-documented risks of side effects from high doses of muscle-building hormones, doctors insist the drugs have legitimate uses -- and genuine benefits for athletes when used wisely. Nobody defends cheaters. At the same time, many doctors and pharmaceutical experts say it's important not to rush to judgment about the chemical agents some of the cheaters appear to be using, particularly testosterone and related hormones in the class of drugs known generally as anabolic-androgenic steroids. Hormones are the messengers of the body, produced in the various glands of the endocrine system to regulate metabolism throughout the body. They are by nature potent molecules that may affect virtually every organ system one way or another. Testosterone, the main male hormone, is one of the main drivers of muscle growth, and has profound effects on mood and sexual function. Many of the steroids in use are synthetic relatives of the natural molecule, reshaped to get different effects -- or to thwart testing methods. ©2004 San Francisco Chronicle

Keyword: Hormones & Behavior
Link ID: 6629 - Posted: 06.24.2010

Subtle wobbles in the Earth's cosmic motions over thousands and millions of years may have influenced the long-term evolution of human beings and their ancestors, experts proposed on the first day of the American Geophysical Union's annual conference in San Francisco. Those wobbles have influenced climate changes that caused bodies of water to shrink and expand over the millennia. In turn, those variations perhaps put stresses on local water-drinkers -- and thus may have accelerated or retarded evolution on the long trek from stone-tool-wielding human ancestors to credit-card-wielding Homo sapiens. Smoking-gun evidence is still lacking for such cosmic influences on humanity's fortunes. The human paleontological record -- bones of our ancestors from millions of years ago -- is relatively scanty compared with the abundant remains of other animal species. For this and other reasons, scientists have trouble distinguishing the long-term evolutionary impact of climate changes from the impacts of other factors, such as random genetic shifts and geological events like volcanic eruptions. Still, powerful indirect evidence for astronomical influence on evolution exists: statistical correlations between Earth's rotation and geological records of lake sizes in Africa, the "cradle of humanity," the scientists said. When those lakes shrink, stagnate or disappear, their loss might favor the emergence of hardier new types of hominids while encouraging the elimination of older, less sturdy breeds. ©2004 San Francisco Chronicle

Keyword: Evolution
Link ID: 6628 - Posted: 06.24.2010

Findings reported this week reveal how an evolutionary innovation involving the sharing of genes between two ant species has given rise to a deep-seated dependency between them for the survival of both species populations. The new work illustrates how genetic exchange through interbreeding between two species can give rise to a system of interdependence at a high level of biological organization--in this case, the production of worker ants for both species. Millions of years before the first modern humans evolved, ants were practicing many of the social innovations we consider to be our own: division of labor, agriculture, and even slavery. Indeed, these traits have been taken to their extreme in many ant species, such as the case of slavemaker ants, which have become so specialized for raiding food from the colonies of other ants that they can no longer feed themselves or raise their younger siblings. Recent work on ants suggests that we may need to add genetic engineering to the list of innovations ants have evolved to employ. In two species of harvester ants, populations have been discovered in which queens mate with males of another species to produce genetically novel hybrid workers. In a new study, Dr. Sara Helms Cahan and colleagues demonstrate that both of the species involved have effectively given up the ability to produce pure-species workers in favor of the hybrids, thereby becoming completely dependent on one another for survival.

Keyword: Evolution
Link ID: 6627 - Posted: 12.29.2004

St. Louis,-- Mice missing a specific protein from their brains react to stress differently. The genetically engineered mice develop an imbalance in a hormone involved in stress responses, and during stressful situations, they behave as if they are depressed. Genetic variations in the same protein may be a significant cause of human depression, according to researchers at Washington University School of Medicine in St. Louis. Their report will be published in the Proceedings of the National Academy of Sciences, appearing on-line at the journal's website during the week of Dec. 27 to 31, 2004 and in an upcoming print issue. "A major obstacle to understanding depression has been finding what triggers its onset," says Maureen Boyle, predoctoral fellow and first author of the report. "We felt it was important to look at elements that regulate the body's stress system." In response to stress, the brain signals the adrenal gland to release hormones, including glucocorticoid, a hormone that preserves physiological equilibrium in many organs. Because proper levels of glucocorticoid are important for normal function, the brain closely monitors and regulates the hormone. "We wanted to find out if depression stems directly from the inability to sense glucocorticoid in the brain," says senior author Louis Muglia, Ph.D., associate professor of pediatrics, of molecular biology and pharmacology and of obstetrics and gynecology. "To test this, we developed an animal model that would tell us if changes in glucocorticoid receptor function could impart the animal equivalent of depression."

Keyword: Depression; Stress
Link ID: 6626 - Posted: 12.29.2004

Genes that control the size and complexity of the brain have undergone much more rapid evolution in humans than in non-human primates or other mammals, according to a new study by Howard Hughes Medical Institute researchers. The accelerated evolution of these genes in the human lineage was apparently driven by strong selection. In the ancestors of humans, having bigger and more complex brains appears to have carried a particularly large advantage, much more so than for other mammals. These traits allowed individuals with “better brains” to leave behind more descendants. As a result, genetic mutations that produced bigger and more complex brains spread in the population very quickly. This led ultimately to a dramatic “speeding up” of evolution in genes controlling brain size and complexity. “People in many fields, including evolutionary biology, anthropology and sociology, have long debated whether the evolution of the human brain was a special event,” said senior author Bruce Lahn of the Howard Hughes Medical Institute at the University of Chicago. “I believe that our study settles this question by showing that it was.” Lahn and his colleagues reported their data in a research article published in the December 29, 2004, issue of the journal Cell. © 2004 Howard Hughes Medical Institute.

Keyword: Evolution; Genes & Behavior
Link ID: 6625 - Posted: 06.24.2010

BERKELEY – Immersed as we are in a sea of smells, how is it we're not continually overwhelmed with fair or foul odors until we actively inhale a rose or sniff the milk for a hint of sourness? University of California, Berkeley, neuroscientists have scanned the brains of people sniffing odors and found an answer. A composite fMRI scan of the brains of 10 subjects undergoing random sniffing trials, where left is the left side of the brain. The piriform cortex is lit up with activity. The temporal (outer) portion of the cortex processes odors and is active whether or not we are paying attention to the smells around us. The frontal (inner) portion and tubercle are most active when we pay attention to the odors. (Christina Zelano, Noam Sobel/UC Berkeley) It turns out that the brain is detecting and processing all the odors around us, but a particular area of the brain actively tunes this out unless the odor reaches a high level, such as when we walk into a cloud of cloying perfume or step in dog poop. When we want to sniff for odors, however, the brain releases the block and begins to pay attention to the smells around us. It even tunes in very precisely to specific smells, allowing us, for instance, to search for a hint of blackberry in a glass of zinfandel. Copyright UC Regents

Keyword: Chemical Senses (Smell & Taste)
Link ID: 6624 - Posted: 06.24.2010

Children who dance are more at risk of having eating disorders like anorexia when they grow up, research has found. It is believed to be the first time a link has been found with dancing for pleasure as a child and such problems. The researchers said the study suggests "participation in dance as a young girl has a long term effect on a woman's eating behaviour". The study, by psychiatrists at the University of Minnesota, is published in the Journal of Sleep Research. Previous studies have found eating disorders are more common in professional ballet dancers, as well as elite athletes. Eating disorders are a serious problem in the UK. It is estimated that at least 165,000 people, mostly women, are affected and that one in 10 will die as a result of their condition. Both anorexia, which involves starving the body of food and bulimia, a cycle of starving and bingeing, are closely linked to mental illness. They now account for more deaths among psychiatric patients than anything else. Media images of super thin models and pop stars are thought to be a major influence on youngsters' eating habits. The desire for a perfect body can mean some lose control of their eating habits and become preoccupied with their appearance. To see if there was any connection between childhood dance and adult eating, researchers recruited 546 women aged from 17 to 55. Each one was quizzed on whether they had danced in childhood. They also completed special questionnaires designed to measure disordered eating behaviours, body image and signs of depression. Just under two-thirds of the women said they had danced when they were children. (C)BBC

Keyword: Anorexia & Bulimia
Link ID: 6623 - Posted: 12.26.2004

Self-knowledge is difficult, as Socrates and virtually every philosopher since Socrates has pointed out. Of all the subjects into which human beings have chosen to inquire, the most resistant to understanding has turned out to be human beings themselves. Indeed, that we researchers have turned out to be our own most recalcitrant subjects must surely constitute one of the leading ironies of post-Enlightenment thought. Human beings just don't seem to fit very well into the scientific picture we have developed of our world. It is hard to comprehend how a universe governed by physical laws could give rise to or contain beings that are conscious, make free decisions, suffer and love -- or, for that matter, beings that are capable of being puzzled at the existence of such beings. Considered as bodies, we are fairly easy to understand. Bodies are just collections of atoms, and seem to behave, more or less, as collections of atoms ought to behave -- putting aside, again, the fact that these bodies happen to be conscious and autonomous and that they think and feel. But these aspects -- the ones connected, in the traditional way of categorizing matters, not so much with our bodies as with our minds -- cannot, of course, be put aside. They are not only the most troublesome features of humans but, for us humans, the most essential. "One agreeable feature of writing about the mind is that it is not necessary to explain why the subject is important," John Searle writes in his new book, "Mind: A Brief Introduction.'' "The operation of the mind -- conscious and unconscious, free and unfree, in perception, action, and thought, in feeling, emotions, reflection, and memory, and in all its other features - - is not so much an aspect of our lives, but in a sense, it is our life." ©2004 San Francisco Chronicle

Keyword: Miscellaneous
Link ID: 6622 - Posted: 06.24.2010

Packing on pounds in huge numbers is a world populace no longer limited to plumped up Americans. The phenomenon is so severe it prompted the World Health Organization to coin a new term —globesity. What's eating those joining the epidemic? Researchers say a multitude of factors, including the possibility that one powerful hunger hormone seems to go haywire in heavy people. Julio Licinio, a pharmacogeneric researcher at UCLA School of Medicine, reported on the importance of this naturally occurring hormone—ghrelin. Licinio collected blood samples every seven minutes, over a 24 hour period, from five obese men and five lean men, then measured their levels of leptin, adiponectin and ghrelin, all hormones known to contribute to appetite regulation and weight gain and loss. Ghrelin, an appetite stimulant created when the stomach and small intestines secrete specialized cells, is the first natural appetite stimulant known to originate from outside the brain, making it a target of interest for researchers trying to manipulate weight. In Licinio's study, ghrelin registered wildly different levels of activity at different times in each subject group, surprising his research team. "When we looked at the data from the obese subjects, we saw that they had the same breakfast, lunch and dinner increases, but at night the levels were flat," he explains. "So, the way we interpreted these results is that we think that obese people in a sense are more sensitive to the hormone during the day and they don't make much of it at night. And in the lean people, they make more of it at night and…they sleep through their cravings.…so they're protected from overeating." © ScienCentral, 2000- 2004

Keyword: Obesity
Link ID: 6621 - Posted: 06.24.2010

St. Louis, -- Researchers knew that prions, the misfolded proteins that cause mad cow disease and other brain disorders, were killing off a class of important brain cells in a transgenic mouse model. But when they found a way to rescue those cells, they were astonished to discover the mice still became sick. Now they believe previous efforts to find the beginnings of the mouse disorder may have been focused on the wrong part of the brain cell and are plotting new directions for research. In a study that appears in the Jan. 1 issue of the Proceedings of the National Academy of Sciences, scientists report evidence that clinical symptoms in the mice are produced by damage to synapses, the areas where nerve cell branches come together for communication. "This could have important therapeutic implications," says senior author David Harris, M.D, Ph.D, professor of cell biology and physiology at Washington University School of Medicine in St. Louis. "There's a great deal of effort being put into developing treatments for neurodegenerative disorders that would inhibit neuron death. Our results suggest that if we just prevent cell death without doing something to maintain the functionality of the synapse, patients may still get sick."

Keyword: Prions; Apoptosis
Link ID: 6620 - Posted: 12.26.2004

SYDNEY, AUSTRALIA: Fit, well-fed male field crickets die young because they spend too much time courting members of the opposite sex, according to research by Australian scientists in the latest edition of Nature. The results reveal how male crickets (Teleogryllus commodus) fed on a high protein diet engaged in more "sexual calling" and died sooner than males reared on a low protein diet. The well-fed males also died earlier than well-fed female crickets (females don't "call" to males). The scientists manipulated the crickets' dietary intake by feeding high, medium and low protein diets to three different groups. "The high protein fed male crickets spent the extra capital that they got from a better diet on mating behaviour, which shortened their longevity," says Dr Luc Bussiere, a UNSW postdoctoral research fellow and co-author to the study. "So it's obvious that for these crickets, a long life isn't all it's cracked up to be." "Supporting the idea that well-fed crickets reduced longevity was a consequence of heightened sexual display ("calling)" was the finding that males raised on both high and medium protein diets lost a greater proportion of their body weight after each night's "calling" than those fed on a low protein diet," says UNSW's Dr John Hunt, an ARC postdoctoral research fellow.

Keyword: Sexual Behavior
Link ID: 6619 - Posted: 12.26.2004

(Kingston, ON) – Birds that migrate early in the season may have a distinct advantage when it comes to attracting the opposite sex, say researchers from Queen's University and the Smithsonian Institution. And it's all about the feathers. Researchers were surprised to discover that the timing of a male songbird's reproduction cycle affects the colour of his feathers and may have important implications for his success in attracting mates. When migratory songbirds raise their young extremely late in the summer, many don't have time to molt (shed their feathers and replace with new growth) before heading south, the new study shows. "This means they must molt at stopover sites on their journey to tropical winter habitats," explains Ryan Norris, who conducted the research as part of his PhD in biology at Queen's, supervised by Professors Laurene Ratcliffe (Queen's Biology) and Peter Marra (Smithsonian Environmental Research Center). "Their replacement feathers, grown en route, are less colourful than those of birds that had time to molt before migration, which may put them at a disadvantage in attracting females the following breeding season," says Dr. Norris. "Both findings – that molting in some songbirds occurs after migration has begun, and that their new feathers are duller in colour – were surprising."

Keyword: Sexual Behavior
Link ID: 6618 - Posted: 06.24.2010