By Mary Bates It's an oft-repeated idea that blind people can compensate for their lack of sight with enhanced hearing or other abilities. The musical talents of Stevie Wonder and Ray Charles, both blinded at an early age, are cited as examples of blindness conferring an advantage in other areas. Then there's the superhero Daredevil, who is blind but uses his heightened remaining senses to fight crime. It is commonly assumed that the improvement in the remaining senses is a result of learned behavior; in the absence of vision, blind people pay attention to auditory cues and learn how to use them more efficiently. But there is mounting evidence that people missing one sense don't just learn to use the others better. The brain adapts to the loss by giving itself a makeover. If one sense is lost, the areas of the brain normally devoted to handling that sensory information do not go unused — they get rewired and put to work processing other senses. A new study provides evidence of this rewiring in the brains of deaf people. The study, published in The Journal of Neuroscience, shows people who are born deaf use areas of the brain typically devoted to processing sound to instead process touch and vision. Perhaps more interestingly, the researchers found this neural reorganization affects how deaf individuals perceive sensory stimuli, making them susceptible to a perceptual illusion that hearing people do not experience. These new findings are part of the growing research on neuroplasticity, the ability of our brains to change with experience. A large body of evidence shows when the brain is deprived of input in one sensory modality, it is capable of reorganizing itself to support and augment other senses, a phenomenon known as cross-modal neuroplasticity. © 2012 Scientific American

Keyword: Vision; Hearing
Link ID: 17281 - Posted: 09.19.2012

Children and teens with higher levels of BPA, a chemical used in canned foods, are more likely to be overweight and obese but whether the chemical caused the weight gain can’t be answered. The issue of obesity is addressed in Tuesday's online edition of the Journal of the American Medical Association. In one U.S. study, researchers wanted to test the idea that hormone-like chemicals like bisphenol A, also called BPA, could be contributing to childhood obesity by disrupting kids' metabolism. BPA is used to make hard plastics for food and beverage containers. It also found in the lining of many metal cans. Dr. Leonardo Trasande of the New York University School of Medicine and his co-authors looked at BPA concentrations in the urine of 2,838 Americans aged six to 19 as well as body mass index scores. "Urinary BPA concentrations was significantly associated with obesity in this cross-sectional study of children and adolescents," the study's authors concluded. The researchers weren't able to tell which came first, the obesity or BPA concentrations. © CBC 2012

Keyword: Obesity; Neurotoxins
Link ID: 17280 - Posted: 09.19.2012

Some people who are severely obese and have gastric bypass surgery may be able to keep weight off for six years, giving them reduced risks of cardiovascular problems and diabetes, a U.S. study finds. The study focused on 1,156 adults with a body mass index of 35 or higher — which is considered severely obese — and who had the bypass surgery. They were compared with 739 other severely obese people in two groups who did not get the surgery. "At six years, 96 per cent of surgical patients had maintained more than 10 per cent weight loss from baseline and 76 per cent had maintained more than 20 per cent weight loss," Ted Adams of the University of Utah School of Medicine and his co-authors wrote in Tuesday’s issue of the Journal of the American Medical Association. All cardiovascular risk factors improved or stayed the same among those who received a type of gastric bypass surgery called Roux-en-Y compared with those who did not, Adams said. Other differences at the end of the study included: Mortality rate three per cent for surgery patients, three per cent for obese patients who were evaluated and one per cent among the control group of obese adults. Diabetes remission 62 per cent for surgery, eight per cent in control group 1 and six per cent in control group 2. © CBC 2012

Keyword: Obesity
Link ID: 17279 - Posted: 09.19.2012

By GRETCHEN REYNOLDS Most people who start working out in hopes of shedding pounds wind up disappointed, a lamentable circumstance familiar to both exercisers and scientists. Multiple studies, many of them covered in this column, have found that without major changes to diet, exercise typically results in only modest weight loss at best (although it generally makes people much healthier). Quite a few exercisers lose no weight. Some gain. But there is encouraging news about physical activity and weight loss in a new study by researchers at the University of Copenhagen. It found that exercise does seem to contribute to waist-tightening, provided that the amount of exercise is neither too little nor, more strikingly, too much. To reach that conclusion, the Danish scientists rounded up a group of pudgy and sedentary young men, a segment of the population increasingly common in Denmark, as elsewhere in the world. The volunteers, most in their 20s or early 30s, visited the scientists’ lab to undergo baseline measurements of their aerobic fitness, body fat, metabolic rates and general health. None had diabetes, high blood pressure or heart disease and, while heavy, they were not obese. The men were then randomly assigned to exercise or not. The non-exercisers, who served as controls, returned to their former routines, with no change to their diets or sedentary ways. A second group began 13 weeks of almost daily moderate workouts, consisting of jogging, cycling or otherwise sweating for about 30 minutes, or until each man had burned 300 calories (based on his individual metabolic rate). Copyright 2012 The New York Times Company

Keyword: Obesity
Link ID: 17278 - Posted: 09.19.2012

By James Gallagher Health and science reporter, BBC News Up to a million people in the UK have "completely preventable" severe headaches caused by taking too many painkillers, doctors have said. They said some were trapped in a "vicious cycle" of taking pain relief, which then caused even more headaches. The warning came as part of the National Institute for Health and Clinical Excellence's (NICE) first guidelines for treating headaches. It is also recommending acupuncture in some circumstances. "Medication overuse headaches" feel the same as other common headaches or migraines. There is no definitive UK data on the incidence of the condition, but studies in other countries suggest 1-2% of people are affected, while the World Health Organization says figures closer to 5% have been reported. While painkillers would be many people's instant response, they could be making sufferers feel even worse. Prof Martin Underwood, from Warwick Medical School, who led the NICE panel, said: "This can end up getting into a vicious cycle where your headache gets worse, so you take more painkillers, so your headache gets worse and this just becomes worse and worse and worse. BBC © 2012

Keyword: Pain & Touch
Link ID: 17277 - Posted: 09.19.2012

In May, my six-year-old daughter, Julia, smashed into our front door handle and got a deep, bloody gash in her forehead. We rushed her, head wrapped like a tiny mummy, to the medical center at MIT, where we generally go for pediatric care. Julia wept while the nurse cleaned and examined her lacerated skin. After a short exam, she sent us to the emergency department at Children’s Hospital Boston for stitches. “How bad is that, generally?” I asked, having never experienced suturing either for myself or my cautious, risk-averse, older daughter. “It can be traumatic,” the nurse said. Julia cried, “I don’t want stitches.” It’s a large needle, but Julia is too busy coloring to notice. So I braced myself for the worst: an endless wait and nerve-wracking bustle; screaming, germ-laden children and brusque, end-of-shift staff. But more than anything, I dreaded the inevitable pain in store for my small child with the deep cut. (I know, kids get banged up on the path to adulthood and some pain is unavoidable. Still, when bloody heads are involved, I tend to overreact.) Indeed, I was in full Mama Bear mode when into our exam room strode Dr. Baruch Krauss, the attending physician that evening. Copyright Trustees of Boston University

Keyword: Pain & Touch; Attention
Link ID: 17276 - Posted: 09.19.2012

By Laura Sanders A dose of Ritalin makes healthy women more reckless in a gambling game. After taking the stimulant, participants in an experiment shifted their betting strategy and kept playing even when faced with stakes too high for most folks. Though solid numbers are scarce, evidence suggests that many healthy people turn to Ritalin (also known as methylphenidate) and other stimulants to boost mental capacity. Some college students, for instance, rely on these “smart pills” to focus attention in cram sessions before tests. The new results, published in the Sept. 19 Journal of Neuroscience, suggest that the drugs might have unanticipated consequences for these people, says study coauthor Daniel Campbell-Meiklejohn of New York University. Scientists have known that the very same drug has an opposite effect in people with attention deficit hyperactivity disorder and a kind of dementia, normalizing these people’s risky behavior. Scientists can’t yet explain Ritalin’s divergent effects, but they suspect that variations in how the brain handles the chemical messenger dopamine may be involved. Researchers enlisted 40 healthy women to take either Ritalin or a placebo, and later play a gambling game. The game was rigged so that the players would quickly rack up a loss and then have to choose whether to double-down in the hopes of recovering their money. “That’s the sad part of the game,” says Campbell-Meiklejohn, who conducted the study while at Aarhus University in Denmark. “You really can’t win.” © Society for Science & the Public 2000 - 2012

Keyword: Drug Abuse; ADHD
Link ID: 17275 - Posted: 09.19.2012

2012 by Graham Lawton My usual pick-me-up on a Monday morning is a cup of coffee. Today it's going to be something very different. I've been up since 6 am. I've had a breath test for alcohol, a urine test for drugs and a psychological test for mental health. Then I'm handed a red pill and a glass of water. I swallow it… and I'm told to relax. Which is easier said than done when you don't know if you've just taken vitamin C or 83 milligrams of pure MDMA. Half an hour later I'm inside an fMRI brain scanner, my head clamped in place and a visor over my face. It's noisy and claustrophobic but I'm reassured by the panic button in my hand and a voice from the control room. And then I start to feel it. A tingle of energy, like pins and needles, starts in the pit of my stomach and rises slowly, not unpleasant but not exactly pleasurable either. It builds in intensity, then breaks into a wave of bliss. The placebo effect can be powerful but when it happens again, I'm in no doubt. I'm coming up. I'm taking part in a groundbreaking study on MDMA, the drug commonly known as ecstasy. The research is run by David Nutt of Imperial College London, a former government adviser and one of the few UK researchers licensed to study class-A drugsMovie Camera. His main aim is to discover what MDMA does to the human brain, something that, remarkably, has never been done before. A second goal is to study MDMA as a therapy for post-traumatic stress disorder. © Copyright Reed Business Information Ltd

Keyword: Drug Abuse; Brain imaging
Link ID: 17274 - Posted: 09.19.2012

by Virginia Morell Imagine hearing a distant roll of thunder and wondering what caused it. Even asking that question is a sign that you, like all humans, can perform a type of sophisticated thinking known as "causal reasoning"—inferring that mechanisms you can't see may be responsible for something. But humans aren't alone in this ability: New Caledonian crows can also reason about hidden mechanisms, or "causal agents," a team of scientists report today in the Proceedings of the National Academy of Sciences. It's the first time that this cognitive ability has been experimentally demonstrated in a species other than humans, and the method may help scientists understand how this type of reasoning evolved, the researchers say. Causal reasoning is "one of the most powerful human abilities," says Alison Gopnik, a psychologist at the University of California, Berkeley, who was not involved in the study. "It's at the root of our understanding of the world and one another." Indeed, it is the key mental ability for many things humans do, including inventing, making, and using tools. We develop this ability early in life: A 2007 study in Developmental Psychology reported that human infants as young as 7 months old understand that when a beanbag is tossed from behind a screen, something or someone must have thrown it. The infants infer that a "causal agent" must be involved in the motion of the flying beanbag. But why should this ability be limited to humans? "It seems like it would make good sense for crows and many other animals to be able to distinguish between the wind rustling tree limbs and an unseen animal crashing through the canopy," says Alex Taylor, an evolutionary psychologist at the University of Auckland in New Zealand and the lead author of the new study. Because New Caledonian crows are also inventive and skillful tool-users, Taylor and his colleagues thought the birds might have causal reasoning skills similar to those of humans. © 2010 American Association for the Advancement of Science

Keyword: Intelligence; Evolution
Link ID: 17273 - Posted: 09.18.2012

By DAVID TULLER Chronic fatigue syndrome is not caused by a mouse retrovirus, according to a study initiated by the National Institutes of Health to settle what had become a contentious scientific question. The long-awaited results, posted online Tuesday in the journal mBio, found no link between the illness, also called myalgic encephalomyelitis, and mouse leukemia retroviruses, including one called XMRV. Two earlier studies had identified higher levels of the viruses in patients with chronic fatigue syndrome. Later research did not confirm the finding, and scientists blamed laboratory contamination for the earlier results. The N.I.H. asked Dr. Ian Lipkin, a virologist at Columbia, to investigate. Dr. Lipkin recruited in the effort scientists who initially reported the link to mouse retroviruses, and they serve as authors on the mBio paper. In the study, none of the researchers reported finding mouse leukemia viruses in any of 293 blood samples, half from people with chronic fatigue syndrome and half from those without it. An estimated one million people in the United States have the condition; many are severely disabled and homebound. Dr. Lipkin said that he viewed chronic fatigue syndrome as a major illness and intended to use blood samples he had obtained to investigate the causes. Copyright 2012 The New York Times Company

Keyword: Stress; Depression
Link ID: 17272 - Posted: 09.18.2012

By Frances Stead Sellers Carolyn McCaskill remembers exactly when she discovered that she couldn’t understand white people. It was 1968, she was 15 years old, and she and nine other deaf black students had just enrolled in an integrated school for the deaf in Talledega, Ala. When the teacher got up to address the class, McCaskill was lost. “I was dumbfounded,” McCaskill recalls through an interpreter. “I was like, ‘What in the world is going on?’ ” The teacher’s quicksilver hand movements looked little like the sign language McCaskill had grown up using at home with her two deaf siblings and had practiced at the Alabama School for the Negro Deaf and Blind, just a few miles away. It wasn’t a simple matter of people at the new school using unfamiliar vocabularly; they made hand movements for everyday words that looked foreign to McCaskill and her fellow black students. So, McCaskill says, “I put my signs aside.” She learned entirely new signs for such common nouns as “shoe” and “school.” She began to communicate words such as “why” and “don’t know” with one hand instead of two as she and her black friends had always done. She copied the white students who lowered their hands to make the signs for “what for” and “know” closer to their chins than to their foreheads. And she imitated the way white students mouthed words at the same time as they made manual signs for them. Whenever she went home, McCaskill carefully switched back to her old way of communicating. © 1996-2012 The Washington Post

Keyword: Language
Link ID: 17271 - Posted: 09.18.2012

By HARRIET BROWN A few years ago, Mercedes Carnethon, a diabetes researcher at the Feinberg School of Medicine at Northwestern University, found herself pondering a conundrum. Obesity is the primary risk factor for Type 2 diabetes, yet sizable numbers of normal-weight people also develop the disease. Why? In research conducted to answer that question, Dr. Carnethon discovered something even more puzzling: Diabetes patients of normal weight are twice as likely to die as those who are overweight or obese. That finding makes diabetes the latest example of a medical phenomenon that mystifies scientists. They call it the obesity paradox. In study after study, overweight and moderately obese patients with certain chronic diseases often live longer and fare better than normal-weight patients with the same ailments. The accumulation of evidence is inspiring some experts to re-examine long-held assumptions about the association between body fat and disease. Dr. Carl Lavie, medical director of cardiac rehabilitation and prevention at the John Ochsner Heart and Vascular Institute in New Orleans, was one of the first researchers to document the obesity paradox, among patients with heart failure in 2002. He spent more than a year trying to get a journal to publish his findings. “People thought there was something wrong with the data,” he recalled. “They said, ‘If obesity is bad for heart disease, how could this possibly be true?’ ” But there were hints everywhere. One study found that heavier dialysis patients had a lower chance of dying than those whose were of normal weight or underweight. Overweight patients with coronary disease fared better than those who were thinner in another study; mild to severe obesity posed no additional mortality risks. © 2012 The New York Times Company

Keyword: Obesity
Link ID: 17270 - Posted: 09.18.2012

By MyHealthNewsDaily staff In common weight-loss advice, "get more sleep," should figure just as prominently as "eat less" and "move more," two researchers in Canada argue. There is strong evidence that lack of sleep is contributing to the obesity epidemic, they said, and factors that contribute to obesity that have been given less attention than diet and exercise may at least partly explain why weight-loss efforts fail, according to the researchers. "Among the behavioural factors that have been shown to impede weight loss, insufficient sleep is gaining attention and recognition," the researchers write in their editorial published today (Sept. 17) in the Canadian Medical Association Journal. The researchers pointed to a 2010 study in which participants were randomly assigned to sleep either 5.5 hours or 8.5 hours every night for 14 days. They all cut their daily calorie intake by 680 calories, and slept in a lab. Participants who slept for 5.5 hours lost 55 percent less body fat, and 60 percent more of their lean body mass than those who slept for longer. In other words, the sleep-deprived people held onto their fat tissue, and instead lost muscle. In another study, published in July, researchers looked at 245 women in a six-month weight loss program and found that those who slept more than seven hours a night, and those who reported better quality sleep, were 33 percent more likely to succeed in their weight-loss efforts. © 2012 NBCNews.com

Keyword: Obesity; Sleep
Link ID: 17269 - Posted: 09.18.2012

By Scicurious It’s often interesting to look over the scientific literature, and to see, for lack of a better term, “fashion trends”. Not what style of kahkis the PIs are wearing this fall, but rather neurotransmitters, techniques, behaviors, or models that you can watch go in and out of fashion. There are lots of different reasons for why this occurs, sometimes a new, better model comes along, sometimes the technique is not a versatile as first thought, sometimes the new neurotransmitter field gets extremely “crowded” and people feel they need to branch out. But it’s interesting to see things wax and wane, and to try and see if you can predict where some things are going. For example, when it first appeared on the scene, the technique of optogenetics (stimulating cells to fire by hitting them with light, because you have infected them with a light sensitive channel) was the new hot thing. Optogenetics is still very “now”, and promises to stick around for a bit, as the flexibility of the technique is still being tested. Knockout mice, on the other hand, though they were wildly popular (and are still), are being replaced with things like targeted knockouts of genes that are localized to specific regions, or inducible knockouts that will only become knockouts when you stimulate the system with something in the diet. It’s a more specific technique and so the older technique is gradually becoming less popular. It works the same way for neurotransmitters, the chemicals released between neurons to convey messages. And I’ve been noticing a new one that I think is going to be an up and comer. This chemical is called orexin (or hypocretin, two groups characterized it at the same time and the name war has continued for years now. It looks like orexin is winning out, for while hypocretin is more functionally accurate…orexin sounds a lot better and is easier to say). Orexin was originally noticed due to two main behaviors: sleep, and appetite. Orexin is a powerful mediator of something called arousal (what you might also call attention or wakefulness, though it’s not quite the same as either). In fact, the most common form of narcolepsy is due to a lack of orexin in the brain. © 2012 Scientific American

Keyword: Obesity; Anorexia & Bulimia
Link ID: 17268 - Posted: 09.18.2012

by Michael Marshall The human brain may be the most complex object in the universe, but its construction mostly depends on one thing: the shape of neurons. Different kinds of neuron are selective about which other neurons they connect to and where they attach. Specific signalling chemicals are thought to be vital in guiding this process. Henry Markram of the Swiss Federal Institute of Technology in Lausanne and colleagues built 3D computer models of the rat somatosensory cortex, each containing a random mix of cell types found in rat brains, but no signalling chemicals. Nevertheless, 74 per cent of the connections ended up in the correct place, merely by allowing the cells to develop into their normal shape. The results suggest that much of the brain could be mapped without incorporating signalling chemicals. This is good news for neuroscientists struggling to map the brain's dizzying web of connections. "It would otherwise take decades to map each synapse in the brain," says Markram. The work could also help untangle the causes of conditions like schizophrenia that are thought to be caused by flaws in brain wiring. If Markram's work proves correct, malformed neurons that don't connect up properly could be a factor. Journal reference: Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1202128109 © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain
Link ID: 17267 - Posted: 09.18.2012

By Melinda Wenner Moyer Read any Web forum, and you'll agree: people are meaner online than in “real life.” Psychologists have largely blamed this disinhibition on anonymity and invisibility: when you're online, no one knows who you are or what you look like. A new study in Computers in Human Behavior, however, suggests that above and beyond anything else, we're nasty on the Internet because we don't make eye contact with our compatriots. Researchers at the University of Haifa in Israel asked 71 pairs of college students who did not know one another to debate an issue over Instant Messenger and try to come up with an agreeable solution. The pairs, seated in different rooms, chatted in various conditions: some were asked to share personal, identifying details; others could see side views of their partner's body through webcams; and others were asked to maintain near-constant eye contact with the aid of close-up cameras attached to the top of their computer. Far more than anonymity or invisibility, whether or not the subjects had to look into their partner's eyes predicted how mean they were. When their eyes were hidden, participants were twice as likely to be hostile. Even if the subjects were both unrecognizable (with only their eyes on screen) and anonymous, they rarely made threats if they maintained eye contact. Although no one knows exactly why eye contact is so crucial, lead author and behavioral scientist Noam Lapidot-Lefler, now at the Max Stern Yezreel Valley College in Israel, notes that seeing a partner's eyes “helps you understand the other person's feelings, the signals that the person is trying to send you,” which fosters empathy and communication. © 2012 Scientific American,

Keyword: Aggression; Emotions
Link ID: 17266 - Posted: 09.17.2012

Nicky Guttridge Subtle differences in the DNA of honeybees are reflected in the bees' roles within the hive. These DNA modifications are normally fixed, but research published today in Nature Neuroscience1 reveals the first example of reversible changes to DNA associated with behaviour. All honeybees (Apis mellifera) are born equal, but this situation doesn’t last long. Although genetically identical, the bees soon take on the specific roles of queen or worker. These roles are defined not just by behavioural differences, but by physical ones. Underlying them are minor modifications to their DNA: ‘epigenetic’ changes that leave the DNA sequence intact, but that add chemical tags in the form of methyl (CH3) molecules to sections of the DNA. This in turn alters the way a gene is expressed2. Once a bee is a queen or worker, they fulfil that role for life — the change is irreversible. But that is not the case for the subdivisions among the workers. The workers start out as nurses, which look after and feed the queen and larvae, and most then go on to become foragers, which travel out from the hive in search of pollen. Again the two types have very different methylation patterns in their DNA. This time, however, as the latest results show, the DNA modifications are reversible: if a forager reverts to being a nurse, its methylation pattern reverts too. © 2012 Nature Publishing Group

Keyword: Genes & Behavior; Epigenetics
Link ID: 17265 - Posted: 09.17.2012

By Jorge Cham and Dwayne Godwin [Graphic novel format.] Dwayne Godwin is a neuroscientist at the Wake Forest University School of Medicine. Jorge Cham draws the comic strip Piled Higher and Deeper at www.phdcomics.com. © 2012 Scientific American,

Keyword: Pain & Touch
Link ID: 17264 - Posted: 09.17.2012

By James Gallagher Health and science reporter, BBC News Having a highly demanding job, but little control over it, could be a deadly combination, UK researchers say. They analysed 13 existing European studies covering nearly 200,000 people and found "job strain" was linked to a 23% increased risk of heart attacks and deaths from coronary heart disease. The risk to the heart was much smaller than for smoking or not exercising, the Lancet medical journal report said. The British Heart Foundation said how people reacted to work stress was key. Job strain is a type of stress. The research team at University College London said working in any profession could lead to strain, but it was more common in lower skilled workers. Doctors who have a lot of decision-making in their jobs would be less likely to have job strain than someone working on a busy factory production line. Freedom There has previously been conflicting evidence on the effect of job strain on the heart. In this paper, the researchers analysed combined data from 13 studies. At the beginning of each of the studies, people were asked whether they had excessive workloads or insufficient time to do their job as well as questions around how much freedom they had to make decisions. BBC © 2012

Keyword: Stress
Link ID: 17263 - Posted: 09.17.2012

By BENEDICT CAREY Scientists have designed a brain implant that sharpened decision making and restored lost mental capacity in monkeys, providing the first demonstration in primates of the sort of brain prosthesis that could eventually help people with damage from dementia, strokes or other brain injuries. The device, though years away from commercial development, gives researchers a model for how to support and enhance fairly advanced mental skills in the frontal cortex of the brain, the seat of thinking and planning. The new report appeared Thursday in The Journal of Neural Engineering. In just the past decade, scientists have developed brain implants that improve vision or allow disabled people to use their thoughts to control prosthetic limbs or move computer cursors. The new paper, led by researchers at Wake Forest Baptist Medical Center and the University of Southern California, describes a device that improves brain function internally, by fine-tuning communication among neurons. Previous studies have shown that a neural implant can do this for memory in rodents, but the new report extends that work significantly, experts said — into brains that are much closer to those of humans. In the study, researchers at Wake Forest trained five rhesus monkeys to play a picture-matching game. The monkeys saw an image on a large screen — of a toy, a person, a mountain range — and tried to select the same image from a larger group of images that appeared on the same screen a little while later. The monkeys got a treat for every correct answer. After two years of practice, the animals developed some mastery, getting about 75 percent of the easier matches correct and 40 percent of the harder ones, markedly better than chance guessing. © 2012 The New York Times Company

Keyword: Learning & Memory; Robotics
Link ID: 17262 - Posted: 09.15.2012