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Do human newborns develop their preference for speech through in-utero eavesdropping, or is their attraction to the human voice innate? It's a bedevilling question to test, but one that's central to understanding the origins and dynamics of humans' unique propensity for speech. Now a McGill University psychologist believes she's separated out the complicating effects of the uterine sound barrier. And the results, says Dr. Athena Vouloumanos, point to a genetic predilection for listening in on speech in preference to other, similar sounds. "It's well established that neonates have a preference for speech above other sounds, but where does this come from? Is it something that's built in and there's something about the speech signal that they're tuned to listen to without the benefit of experience, or does it come from their prenatal experience in the womb? I think we've shown that there's an experience-independent component to newborns' preference for speech," says Dr. Vouloumanos, an Assistant Professor in McGill's Department of Psychology in Montreal, Canada. She'll be presenting the findings of her latest research at the annual meeting of the American Association for the Advancement of Science in St. Louis, February 17. Neural and cochlear development is such that at about six months gestation the fetus begins to hear a range of frequencies. Thus, there's the possibility that newborns prefer listening to speech just because they're used to it from their in-utero tuning in. Copyright 2002, Science in Africa,
Keyword: Language; Hearing
Link ID: 8730 - Posted: 03.29.2006
We all teeter and tip while first learning to walk but, for adults like retired electrical engineer Fred Kawabata — whose sense of balance was damaged when a childhood disease flared up as an adult — a simple stroll becomes something to learn all over again. "When it first struck me I was flat on my back," explains 65-year-old Kawabata from Beaverton, Oregon. "I had vertigo, I was dizzy, I could hardly get out of bed." Almost ten years ago the chicken pox he had suffered as a kid came back in the form of shingles. The virus that lay dormant for all those years in his nerves attacked the vestibular nerves of Kawabata's the inner ear, leaving him rather unsteady on his feet because of a balance disorder. "In about a month, I could get up and walk around although it was still very uncomfortable. It took a couple months before I could be reasonably comfortable walking around," he recalls. "[Now], when I'm walking on a flat surface, I generally don't have to think about it very much. But if I'm on an uneven surface like when I'm hiking and the trail is rough, then I really have to think about it. © ScienCentral, 2000-2006.
Keyword: Movement Disorders
Link ID: 8729 - Posted: 06.24.2010
It's usually reasonable to assume that eating more calories than you burn is what makes you gain weight. We tend to faithfully adhere to that belief, otherwise, why would we ever bother with all that dieting and exercise? But research now shows that viruses — specifically certain human adenoviruses — may actually be causing some cases of obesity. Adenoviruses are usually associated with common infections like colds and pink eye. They can also cause enteritis and diarrhea. But as nutritional scientist Leah Whigham says, "Those are the acute responses. We're finding that some of these viruses also cause a more chronic response that involves increased fatness." Whigham and her team at the University of Wisconsin, Madison tested several human adenoviruses for their ability to increase fat in both live chickens and in cell culture. The groundwork for this new study was laid by earlier research of Dr. Nikhil Dhurandhar. Dhurandhar first discovered that viruses could cause obesity while working with patients in India. He noticed that people who had been exposed to a chicken adenovirus called SMAM-1 were consistently fatter than those who had had no exposure. Later on, having moved to the U.S., Dhurandhar collaborated with other researchers to study whether human adenoviruses, which are common throughout the human population, could be having a similar effect. This led to the discovery that the human adenovirus Ad-36 caused significant fat increases in animals, and what's more, was associated with obesity in humans. © ScienCentral, 2000-2006.
Keyword: Obesity
Link ID: 8728 - Posted: 06.24.2010
By Laura Blackburn A little bit of stress can sometimes be good for us. It activates hormones that help us breathe more easily, for example. But for asthmatics, stress only makes things worse. Now, a group of researchers believe they have found a molecular mechanism that could help explain why. Stress works its effects partially through the hormones adrenaline and cortisol. Usually, adrenaline opens up airways by docking with the beta2-adrenergic receptors (beta2-AR) on cells. Cortisol helps mute allergic responses by connecting to the glucocorticoid receptors (GR). To understand why asthmatics get worse with stress, psychologists Greg Miller and Edith Chen from the University of British Columbia in Vancouver, Canada, graded the everyday stress levels of 38 healthy and 39 asthmatic children. They then looked at the levels of beta2-AR and GR gene expression in each child’s white blood cells. Healthy children who were stressed had higher levels of beta2-AR expression than did those who were chilled out. This would explain why adrenaline could ease the breathing of the stressed kids: There are more cell receptors to pick up the signal. The pattern was reversed in the asthmatic children; those with chronic stress had lower beta2-AR expression levels than those who were typically relaxed. While there wasn't a clear relationship between stress and GR expression levels, the researchers did discover that profound stress had an impact. If an already stressed child experienced a very stressful event, such as the death of a relative, gene expression of both receptors dropped. © 2006 American Association for the Advancement of Science.
Keyword: Stress; Neuroimmunology
Link ID: 8727 - Posted: 06.24.2010
A national research team led by the University of Cincinnati's Bibiana Bielekova, MD, report new insights into how anti-rejection drug helps MS patients Discovery of the mechanism of a drug being tested for the treatment of multiple sclerosis (MS) has revealed that it's not only more effective than first thought, but might also help in the management of other autoimmune diseases, organ transplant rejection and even cancer. A research team led by the University of Cincinnati's Bibiana Bielekova, MD, report new insights into the role of the MS drug daclizumab (Zenapax) in the March 27 online version of the Proceedings of the National Academy of Sciences. The article will appear in print April 11. The exact cause of MS is unknown, but one theory is that it may it be triggered by exposure to a viral infection or environmental influences. The disease takes different courses in different people and can go into remission for many years, recurring occasionally or progressing quickly into degeneration of all motor functions that control muscles, strength, vision and balance. The very progressive form of the disease can end in death. Scientists have long thought that in MS the specific white cells (T-cells) that fight off infection actually turn on the body they are supposed to protect, attacking the myelin sheath that protects the nerves.
Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 8726 - Posted: 03.29.2006
Roxanne Khamsi Stem cells can help restore some function in injured rats with spinal cord damage, suggests a new study. The team, led by Michael Fehlings at the Toronto Western Research Institute, Canada, used stem cells taken from mice brains. They injected a finely tuned cocktail of growth hormones, anti-inflammatory drugs and the cells into rats with crushed spines. Although rats not given the stem cell treatment naturally regained some of their hind limb function two weeks after the injury, they were extremely uncoordinated. The stem cell treatment improved limb function, although it did not completely restore it. The study is important, says Phillip Popovich at Ohio State University in Columbus, US. He notes that the special cocktail of growth hormones and anti-inflammatory compounds used in the rats could play a crucial role in making stem cell therapies work. However, he cautions that this type of approach might be difficult to administer to humans. “I would think the biggest drawback is the complexity of the approach. From a logistical standpoint, instrumenting catheters and preparing cells for transplantation will be an expensive venture,” he told New Scientist. “Patients aren’t going to be given a pill or a shot.” © Copyright Reed Business Information Ltd.
Keyword: Stem Cells; Regeneration
Link ID: 8725 - Posted: 06.24.2010
By Aalok Mehta A half-hour of cardio work. An hour hitting the weights. Twenty minutes playing video games. Is this the workout of the future? It could be, if the claims Nintendo is making about its "Brain Training" games turn out to be accurate. The games, the first of which is scheduled for U.S. release next month, include a variety of mental exercises the company says are designed to keep aging minds youthful and healthy. Brain Training is "kind of like a treadmill for the mind," said Perrin Kaplan, vice president of marketing and corporate affairs for Nintendo of America. "Brain Age: Train Your Brain in Minutes a Day" will go on sale April 17; its sequel, "Big Brain Academy," will be released June 5. Both games are played on Nintendo's DS handheld system. Nintendo worked with Ryuta Kawashima, a Japanese neurologist, to develop the series. In Nintendo publicity materials, Kawashima explains that people can keep their brains young by repeatedly performing simple, fast-paced mental activities. These include counting the number of syllables in phrases, memorizing words and performing simple math problems. (Kawashima could not be reached for comment.) © 2006 The Washington Post Company
Keyword: Intelligence; Alzheimers
Link ID: 8724 - Posted: 06.24.2010
(Santa Barbara, Calif.) –– Scientists have found that growth hormone, a substance that is used for body growth, is produced in the brain, according to an article published in this week's Proceedings of the National Academy of Sciences. The researchers -- from three institutions –– found that growth hormone is produced within the hippocampus, a structure deep inside the brain that is involved in memory and emotion. The scientists also found that more growth hormone is produced in females than in males, and more in adults. More growth hormone was also produced in response to estrogen. The study has implications for menopausal women using estrogen replacement therapy and for athletes taking growth hormone and anabolic steroids to increase muscle mass. The scientists suspect that reasoning and mood may also be affected by these differences in the amount of growth hormone in the brain. "Growth hormone has been associated with growth of muscles and bones, and the production of it was believed to lie mainly in the pituitary gland," said co-author Ken S. Kosik, co-director of the Neuroscience Research Center at the University of California, Santa Barbara. "No one had thought too much about what growth hormone might be doing in the brain. Hormones in the brain may not be obvious compared to what they are doing in the rest of the body."
Keyword: Hormones & Behavior; Sexual Behavior
Link ID: 8723 - Posted: 06.24.2010
By Carel van Schaik Even though we humans write the textbooks and may justifiably be suspected of bias, few doubt that we are the smartest creatures on the planet. Many animals have special cognitive abilities that allow them to excel in their particular habitats, but they do not often solve novel problems. Some of course do, and we call them intelligent, but none are as quick-witted as we are. What favored the evolution of such distinctive brainpower in humans or, more precisely, in our hominid ancestors? One approach to answering this question is to examine the factors that might have shaped other creatures that show high intelligence and to see whether the same forces might have operated in our forebears. Several birds and nonhuman mammals, for instance, are much better problem solvers than others: elephants, dolphins, parrots, crows. But research into our close relatives, the great apes, is surely likely to be illuminating. Scholars have proposed many explanations for the evolution of intelligence in primates, the lineage to which humans and apes belong (along with monkeys, lemurs and lorises). Over the past 13 years, though, my group's studies of orangutans have unexpectedly turned up a new explanation that we think goes quite far in answering the question. © 1996-2006 Scientific American, Inc.
Keyword: Intelligence; Evolution
Link ID: 8722 - Posted: 06.24.2010
Sleeping helps to reinforce what we've learned. And brain scans have revealed that cerebral activity associated with learning new information is replayed during sleep. But, in a study published in the open access journal PLoS Biology, Philippe Peigneux and colleagues at the University of Liege demonstrate for the first time that the brain doesn't wait until night to structure information. Day and night, the brain doesn't stop (re)working what we learn. Taking advantage of the new opportunities offered by 3 Tesla's functional Magnetic Resonance Imaging (fMRI)(*), Philippe Peigneux et al. recorded (or scanned) the cerebral activity of volunteers while they performed a ten-minute auditory attention task every half hour in two sessions spaced out over a few weeks. In each of these sessions, during the half hour between the first two scans of the attention task, the volunteer was given something new to learn. A third scan was then performed after a half-hour rest. During one of the two sessions, the volunteer memorized a route in a virtual city he or she was exploring on a computer. This spatial navigation task is known to be dependent on the hippocampus, a cerebral structure that plays a vital role in learning. The other session was devoted to acquisition by repetition (or procedural learning) of new visuomotor sequences. For this task, it wasn't necessary that the subject be aware of what he or she was learning, and its success depends mainly on the integrity of the striatum and the related motor regions.
Keyword: Sleep; Learning & Memory
Link ID: 8721 - Posted: 03.28.2006
If you think you've got a bad boss, one who loves to chew people out, or if you work with backstabbing co-workers, be thankful you are not a wasp. If you were, chances are your nestmates might bite you to communicate that it is time to leave the nest and forage for the colony, according to research by a University of Washington animal behaviorist. Biting is a way that workers in a colony of the social wasp Polybia occidentalis recruit new foragers to gather water, food and building material in a time of need, said Sean O'Donnell, a UW associate professor of psychology. O'Donnell previously found that biting appears to be an important way of regulating the division of labor among these insects. Now, in the current issue of the journal Animal Behaviour, he describes an experiment in which he artificially removed active foragers from four wasp colonies to see how new foragers are recruited. He found that biting was directed at certain individuals, who previously hadn't left the nest, to induce them to begin foraging. The rate of being bitten increased by an average of 600 percent for these recruited foragers, while biting rates did not increase for other workers. "The fact that biting was specifically directed at recruited foragers shows that biting is the mechanism that the colonies used to activate new foragers," said O'Donnell.
Keyword: Animal Communication
Link ID: 8720 - Posted: 03.28.2006
Loneliness is a major risk factor in increasing blood pressure in older Americans, and could increase the risk of death from stroke and heart disease, new research at the University of Chicago shows. Scholars found that lonely people have blood pressure readings that are as much as 30 points higher than in non-lonely people, even when other factors such as depressive symptoms or perceived stress are taken into account, said Louise Hawkley, Senior Research Scientist with the Center for Cognitive and Social Neuroscience at the University of Chicago, and John Cacioppo, the Tiffany & Margaret Blake Distinguished Service Professor in Psychology. This is equivalent to the difference between a normal blood pressure of 120 and a level of 150 which signifies Stage 1 hypertension. Blood pressure differences between lonely and non-lonely people were smallest at age 50 and greatest among the oldest adults tested, those at retirement age. Hawkley and Cacioppo are authors of the paper, "Loneliness is a Unique Predictor of Age-Related Differences in Systolic Blood Pressure," published in the journal Psychology and Aging. Other co-authors were Christopher Masi, Assistant Professor of Medicine at the University of Chicago, and Jarett Berry of the Department of Preventive Medicine, Northwestern.
Michael Hopkin Does the prospect of public speaking make you panic? Do you run for the hills at the mere mention of spiders? Help could be at hand: researchers have come up with a way to ease the crippling symptoms of phobia. The treatment, developed by a Swiss-led research team, could one day help sufferers to face their fear simply by popping a pill before facing a stressful situation. The researchers hope that it may even have permanent effects, by helping phobics deal with the daunting prospect of undergoing therapy in which they come face to face with their fears. The remedy contains a human hormone called cortisol, which the body produces naturally in times of stress or fear to help subdue the panic response. Previous studies have shown that increased levels of cortisol help us to blank out painful memories and emotions, allowing us to deal more effectively with stressful situations. ©2006 Nature Publishing Group
Keyword: Emotions; Hormones & Behavior
Link ID: 8718 - Posted: 06.24.2010
Tom Simonite A specialised microchip that could communicate with thousands of individual brain cells has been developed by European scientists. The device will help researchers examine the workings of interconnected brain cells, and might one day enable them to develop computers that use live neurons for memory. The computer chip is capable of receiving signals from more than 16,000 mammalian brain cells, and sending messages back to several hundred cells. Previous neuron-computer interfaces have either connected to far fewer individual neurons, or to groups of neurons clumped together. A team from Italy and Germany worked with the mobile chip maker Infineon to squeeze 16,384 transistors and hundreds of capacitors onto an experimental microchip just 1mm squared. When surrounded by neurons the transistors receive signals from the cells, while the capacitors send signals to them. Each transistor on the chip picks up the miniscule change in electric charge prompted when a neuron fires. The change occurs due to the transfer of charged sodium ions, which move in and out of the cells through special pores. Conversely, applying a charge to each capacitor alters the movement of sodium ions, causing a neuron to react. © Copyright Reed Business Information Ltd.
Keyword: Robotics
Link ID: 8717 - Posted: 06.24.2010
Enzymes that can harm the brain immediately after a stroke may actually be beneficial days later, according to new research. Insights from the study could change the way stroke is treated, extending the window for effective treatment from a couple of hours to a couple of weeks. The results may suggest new ideas for drug development. Working with rats, a team from the Harvard Medical School Departments of Radiology and Neurology found that the enzyme matrix metalloproteinase-9 (MMP-9) may help remodel brain tissue seven to 14 days after a stroke. Their findings are published in the April 2006 issue of Nature Medicine, and were made available in an advance online publication on March 26, 2006. Matrix metalloproteinases are a large group of enzymes that help break down the extracellular matrix, a complex structure that surrounds and supports cells. Newer research is showing that MMPs may also contribute to blood vessel growth, as well as the death, proliferation, differentiation, and movement of cells. Sophia Wang, who was a Howard Hughes Medical Institute (HHMI) medical student fellow at Harvard Medical School, is second author of the article. She was deeply involved with the study's data analysis, and established a way to quantify the response of proteins involved in the cell growth and blood vessel remodeling that occurs after stroke. She also assisted with behavioral studies of rats that had received MMPs to see how well they recovered after a stroke. © 2006 Howard Hughes Medical Institute.
Keyword: Stroke
Link ID: 8716 - Posted: 06.24.2010
By Rick Weiss Scientists in Germany said yesterday that they had retrieved easily obtained cells from the testes of male mice and transformed them into what appear to be embryonic stem cells, the versatile and medically promising biological building blocks that can morph into all kinds of living tissues. If similar starter cells exist in the testes of men, as several scientists yesterday said they now believe is likely, then it may not be difficult for scientists to cultivate them in laboratory dishes, grow them into new tissues and transplant those tissues into the ailing organs of men who donated the cells. The technique would have vast advantages over the current approach to growing "personalized" replacement parts -- an approach that has stirred intense political controversy because it requires the creation and destruction of cloned human embryos as stem cell sources. The new work suggests that every male may already have everything he needs to regenerate new tissues -- at least with a little help from his local cell biologist. No one knows whether cells with similar potential exist inside female bodies -- a crucial question if women, too, are to have access to new tissues genetically matched to themselves and so not susceptible to rejection by their immune systems. But recent studies have led many researchers to conclude that the possibility is greater than previously believed. © 2006 The Washington Post Company
Keyword: Stem Cells
Link ID: 8715 - Posted: 06.24.2010
People who mix alcohol with energy drinks like Red Bull can often feel less drunk than they really are, a study suggests. The Brazilian team compared the reactions of 26 men given either alcohol, Red Bull or a combination of both in three drinking sessions. Although the men perceived themselves to be less impaired when taking the mix physical tests proved the opposite. The study is published in Alcoholism: Clinical and Experimental Research. The team, led by psychology professor Maria Lucia Souza-Formigoni of the University of Sao Paulo, said those who mixed the caffeine drinks and alcohol reported an increased sensation of pleasure and a reduction in sleepiness. This had led some to suggest that the combination might reduce the depressive effects of alcohol. But the team's results showed a "considerable disconnect" between the subjects' perceptions and objective measures of their abilities. Professor Souza-Formigoni said: "In Brazil, as in other countries, people believe that Red Bull and other energy drinks avoid the sleepiness caused by alcoholic beverages and increase their capacity to dance all night. Her study in some ways reflected this assumption, with subjects on the combination of Red Bull and alcohol reporting less perception of headache, weakness, dry mouth and impairment of motor coordination. But objective measures of coordination showed Red Bull consumption did not reduce any of the negative effects alcohol has on coordination or visual reaction times. (C)BBC
Keyword: Drug Abuse
Link ID: 8714 - Posted: 03.27.2006
A visit to the doctor might not be your favorite thing, but everything — from the time you spend talking with the doctor to the diploma on the wall — could be helping to make you better. "The ritual of medicine, the context of medicine, is important to take into consideration in healthcare," says Harvard Medical School's Ted Kaptchuk. "There's an implication that how you describe your intervention, what you tell patients, has an impact on how that intervention effects their illness and health." Kaptchuk, who studied Chinese medicine in China, has been studying what's known as the placebo effect. "The effect of giving someone a dummy treatment, a treatment that appears like a real treatment, but actually has none of the active ingredients," he explains. So, Kaptchuk and his research team set out to see if different kinds of dummy treatments, or placebos could reduce patients' chronic arm pain. They compared a fake acupuncture procedure to a pill made of nothing but cornstarch. They found that, "A dummy procedure has a bigger impact on reducing pain than an oral dummy pill," he says. As they reported in the British Medical Journal, the study began by testing the effectiveness of two placebo treatments against active treatments at reducing self-assessed arm pain. "You can't give patients placebos without having a comparison with an act of intervention," explains Kaptchuk. After two weeks, the fake pill and fake acupuncture groups were continued and compared against each other. © ScienCentral, 2000-2006.
Keyword: Pain & Touch
Link ID: 8713 - Posted: 06.24.2010
Psychologists wanting to help old people safely cross the street and otherwise ambulate around this busy world have found that from age 70 and up, safe walking may require solid "executive control" (which includes attention) and memory skills. For the old, slow gait is a significant risk factor for falls, many of which result in disabling fractures, loss of independence or even death. The finding may help explain why cognitive problems in old age, including dementia, are associated with falls. Cognitive tests could help doctors assess risk for falls; conversely, slow gait could alert them to check for cognitive impairment. The findings are in the March issue of Neuropsychology, which is published by the American Psychological Association (APA). Roee Holtzer, PhD, and his colleagues conducted a cross-sectional study of 186 cognitively normal, community-dwelling adults aged 70 and older at New York City's Albert Einstein College of Medicine. Gait speed was tested with and without interference. In the interference conditions, participants had to walk while reciting alternate letters of the alphabet. Performance on cognitive tests of executive control and memory, and to a lesser extent of verbal ability, predicted "gait velocity" (walking speed) tested without interference. For gait velocity tested with interference, only executive control and memory were predictive. Adding interference to the tests of gait allowed the researchers to better simulate the real world, in which walkers continually deal with distractions. The authors conclude that executive control and memory function are important when the individual has to walk in a busy environment.
Keyword: Alzheimers
Link ID: 8712 - Posted: 03.27.2006
People with Korsakoff Syndrome (KS), a brain disorder usually associated with long-term heavy drinking and thiamine deficiency, often have profound deficits in their "explicit memory" or ability to recall recent events. A study in the April issue of Alcoholism: Clinical & Experimental Research looks at a memory process called visuoperceptual learning, a component of "implicit memory," which does not require conscious recollection. Results suggest that individuals with KS retain the ability to learn information that is presented visually, even without a conscious recollection of that learning. "'Explicit events' refer to situations that an individual can consciously recall when asked, 'what did you do yesterday?' or 'what did you do over the holidays?,'" explained Edith Sullivan, a professor in the department of psychiatry and behavioral sciences at Stanford University School of Medicine and corresponding author for the study. "Individuals with KS cannot consciously recall what they did or information presented to them earlier in the day." "Explicit memory is often referred to as 'knowing what' and implicit memory to 'knowing how,'" said Sara Jo Nixon, professor and director of the Neurocognitive Laboratory at the University of Kentucky. "However, the impact of chronic excessive alcohol consumption on implicit memory has been less clear and less frequently studied. Visuoperceptual tasks likely engage a significant component linked to implicit memory functions. Thus, examining implicit memory using such a task in a comparison of Korsakoff alcoholics, non-Korsakoff alcoholics and controls is an effective way of disentangling alcohol's long-term effects on 'knowing how' versus 'knowing what.'
Keyword: Drug Abuse; Learning & Memory
Link ID: 8711 - Posted: 03.27.2006


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