YOU'RE fat, lazy, and only the prospect of mating can propel you into action. But that's just fine - as long as you're an African mole rat. Your fellow colony members will even toil to support you. Zoologists studying the Damaraland mole rat (Cryptomys damarensis) in its native southern Africa have discovered that its colonies are split into two distinct castes of worker. One group is hard-working and industrious; the other is fat and rather work-shy. Damaraland mole rats and naked mole rats are thought to be the only mammal species that live and breed cooperatively, with some colony members devoting their lives to helping others reproduce. To explore their unusual lifestyle, Michael Scantlebury of the University of Pretoria, South Africa, and colleagues in the UK studied the creatures' energy demands and activity levels. They found that the industrious mole rats performed more than 95 per cent of the total work of the colony. The lazy mole rats built up their fat stores, placing a double burden on the colony - doing virtually no work, but requiring more food (Nature, vol 440, p 795). © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior; Evolution
Link ID: 8737 - Posted: 06.24.2010

Helen Pearson Sleep deprivation is costing the United States hundreds of billions of dollars each year. So say the experts behind a report that highlights this burgeoning and oft-ignored health problem. Round-the-clock television and lengthening work days mean that many people spend less time in bed. Although everyone is aware that not getting enough sleep can have ill effects, doctors and researchers are just beginning to realize the toll on our health. To estimate the size of society's sleep problem, and find ways to solve it, a group of sleep-research organizations asked the Institute of Medicine to study the issue. Its 14-person panel released their report yesterday1. The panel says that the impact of poor sleep is "shocking" even to experts in the field. They say that some 50 million to 70 million Americans are suffering from a sleep disorder and countless more from sleep deprivation. Many sleep specialists say that a good night's kip is just as important for health as diet and exercise. The problem "is underappreciated and probably underestimated", says Harvey Colten of Columbia University in New York City, who chaired the panel. ©2006 Nature Publishing Group

Keyword: Sleep
Link ID: 8736 - Posted: 06.24.2010

By Gareth Mitchell Playing virtual reality computer games may help treat the condition known as amblyopia, or lazy eye, say researchers. In patients with amblyopia, one eye works better than the other. Because the amblyopic eye is inferior for some reason, the brain decides to use the good eye. Over time, the neural connection to the bad eye becomes gradually weaker in favour of the good eye. The traditional way of fixing the problem is for patients to force the bad eye to work harder by wearing a patch over the good eye. The treatment usually involves patching for around 400 hours and can cause the eyes not to work together, resulting in double vision. Researchers at Nottingham University say that an experimental treatment using virtual reality (VR) may offer the best of both worlds, encouraging the lazy eye to be more active and getting both eyes to work together. "Traditionally VR has been used to present realistic environments in 3D so you imagine you're there because of the depth of the world around you," said Richard Eastgate of the university's Virtual Reality Applications Research Team. But we're using VR to make something unrealistic. You could call it virtual unreality," he told Digital Planet. "We're actually presenting two different versions of the world to each eye." In one experiment, the team has been trying out a racing game where the computer sends images of the player's own car to the amblyopic eye, but the other cars go to the good eye. Obstacles on the track are sent alternately to each eye, so both eyes team up to get the patient through the game. (C)BBC

Keyword: Vision
Link ID: 8735 - Posted: 03.30.2006

Adrianne Appel More than a million ant specimens—meticulously dried, pinned, and identified—lie in wooden drawers in Harvard University's Museum of Comparative Zoology. But these specimens are hardly gathering dust in their Cambridge, Massachusetts, home. The office of Edward Osborn Wilson—renowned scientist and author, father of sociobiology, and ant expert—is right down the hall. Wilson's body of work is a product of unfailing energy and focus. As a young man he traveled through Europe visiting ant collections. Then as a Harvard professor he spent years driven by what he calls "the amphetamine of ambition"—working 80-hour weeks, teaching, studying ants, and writing. From his work in the field he has personally identified more than 400 new ant species. Now in his late 70s, the man labelled "Darwin's Natural Heir" by Britain's Gaurdian newspaper has not slowed up his nearly lifelong pursuit of collecting and identifying ants, nor has he let the rest of his work lose steam. © 1996-2006 National Geographic Society.

Keyword: Evolution
Link ID: 8734 - Posted: 06.24.2010

Jim Giles Researchers say that a remarkable data set on the developing brain adds to the idea that IQ is a meaningful concept in neuroscience. The study, which is published on page 676 of this issue, suggests that performance in IQ tests is associated with changes in the brain during adolescence. Claims that IQ is a valid measure of intelligence tend to attract angry responses, in part because of studies that have attempted to link group differences in IQ with race. In their 1994 book The Bell Curve, political scientist Charles Murray and psychologist Richard Herrnstein argued that the lower-income status of some US ethnic minorities was linked to below-average IQ scores among those groups. These were in turn attributed to mainly genetic factors. Before that, Harvard University entomologist Edward Wilson provoked outrage with work that proposed evolutionary explanations for human behaviour and individual differences in intelligence; critics called the work racist. And this month, the journal Intelligence printed an editorial note defending its policy regarding the publication of controversial papers. The note comes after a study linking IQ and skin colour (D. I. Templer and H. Arikawa Intelligence 34, 121–139; 2006), published online last November, prompted a string of complaints from scientists. ©2006 Nature Publishing Group

Keyword: Intelligence; Development of the Brain
Link ID: 8733 - Posted: 06.24.2010

Youth with superior IQ are distinguished by how fast the thinking part of their brains thickens and thins as they grow up, researchers at the National Institutes of Health’s (NIH) National Institute of Mental Health (NIMH) have discovered. Magnetic resonance imaging (MRI) scans showed that their brain’s outer mantle, or cortex, thickens more rapidly during childhood, reaching its peak later than in their peers — perhaps reflecting a longer developmental window for high-level thinking circuitry. It also thins faster during the late teens, likely due to the withering of unused neural connections as the brain streamlines its operations. Drs. Philip Shaw, Judith Rapoport, Jay Giedd and colleagues at NIMH and McGill University report on their findings in the March 30, 2006 issue of Nature. “Studies of brains have taught us that people with higher IQs do not have larger brains. Thanks to brain imaging technology, we can now see that the difference may be in the way the brain develops,” said NIH Director Elias A. Zerhouni, M.D. While most previous MRI studies of brain development compared data from different children at different ages, the NIMH study sought to control for individual variation in brain structure by following the same 307 children and teens, ages 5-19, as they grew up. Most were scanned two or more times, at two-year intervals. The resulting scans were divided into three equal groups and analyzed based on IQ test scores: superior (121-145), high (109-120), and average (83-108). “Brainy children are not cleverer solely by virtue of having more or less gray matter at any one age,” explained Rapoport. “Rather, IQ is related to the dynamics of cortex maturation.”

Keyword: Intelligence; Development of the Brain
Link ID: 8732 - Posted: 06.24.2010

Scientists at the National Institutes of Health’s (NIH) National Institute on Alcohol Abuse and Alcoholism (NIAAA) have identified a previously unknown gene variant that doubles an individual’s risk for obsessive-compulsive disorder (OCD). The new functional variant, or allele, is a component of the serotonin transporter gene (SERT), site of action for the selective serotonin reuptake inhibitors (SSRIs) that are today’s mainstay medications for OCD, other anxiety disorders, and depression. “Improved knowledge of SERT‘s role in OCD raises the possibility of improved screening, treatment, and medications development for that disorder,” said Ting-Kai Li, M.D., Director, National Institute on Alcohol Abuse and Alcoholism. “It also provides an important clue to the neurobiologic basis of OCD and the compulsive behaviors often seen in other psychiatric diseases, including alcohol dependence.” Approximately 2 percent of U.S. adults (3.3 million people) have OCD, the fourth most prevalent mental health disorder in the United States. Individuals with OCD have intrusive, disturbing thoughts or images (obsessions) and perform rituals (compulsions) to prevent or banish those thoughts. Many other individuals demonstrate obsessive-compulsive behaviors that do not meet OCD diagnostic criteria but alter the individuals’ lives.

Keyword: OCD - Obsessive Compulsive Disorder; Genes & Behavior
Link ID: 8731 - Posted: 06.24.2010

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.

Keyword: Emotions; Stress
Link ID: 8719 - Posted: 03.28.2006

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