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By Ferris Jabr As a dung beetle rolls its planet of poop along the ground it periodically stops, climbs onto the ball and does a little dance. Why? It's probably getting its bearings. A series of experiments published in the January 18 issue of PLoS ONE shows that the beetles are much more likely to perform their dance when they wander off course or encounter an obstacle. Until now, no one had any idea what a jitterbugging dung beetle was up to. Emily Baird of Lund University in Sweden and her colleagues study how animals with tiny brains—such as bees and beetles—perform complex mental tasks, like navigating the world. The dung beetle intrigues Baird because it manages to roll its dung ball in a perfectly straight line, even though it pushes the ball with its back legs, its head pointed at the ground in the opposite direction. If the six-legged Sisyphus can't see where it's going, how does it stay on its course? Every now and then, a dung beetle stops rolling, mounts its ball and pirouettes. Baird noticed that dung beetles do not dance as often in the lab, where they roll around on flat surfaces, as they do in the field, where the terrain is rough and rocks and clumps of grass often obstruct the beetles' paths. She guessed that by climbing onto a ball of dung four or five times its height, a beetle gets a pretty good vantage point from which to correct any navigational mistakes. But it was only an intuition—she needed evidence. © 2012 Scientific American

Keyword: Animal Migration; Evolution
Link ID: 16274 - Posted: 01.21.2012

The day after TODAY reported on the baffling case of 12 teenage girls at one school who mysteriously fell ill with Tourette's-like symptoms of tics and verbal outbursts, a doctor who is treating some of the girls has come forward to offer an explanation. Dr. Laszlo Mechtler, a neurologist in Amherst, N.Y., says the diagnosis is "conversion disorder," or mass hysteria. "It's happened before, all around the world, in different parts of the world. It's a rare phenomena. Physicians are intrigued by it," Mechtler told TODAY on Wednesday. "The bottom line is these teenagers will get better." On the show Tuesday, psychologist and TODAY contributor Dr. Gail Saltz noted that just because the girls' symptoms may be psychological in origin doesn't make them any less real or painful. “That’s not faking it. They’re real symptoms,” Saltz continued. “They need a psychiatric or psychological treatment. Treatment does work.’’ Conversion disorder symptoms usually occur after a stress event, although a patient can be more at risk if also suffering from an illness. Symptoms may last for days or weeks and can include blindness, inability to speak, numbness or other neurologic problems. It's unclear which of the girls first showed symptoms, or whether any particular event triggered the outbreak. High school cheerleader and art student Thera Sanchez says her tics, stammer and verbal outbursts appeared out of the blue after a nap one day last October. © 2012 msnbc.com

Keyword: Stress; Emotions
Link ID: 16273 - Posted: 01.19.2012

Elderly people with dementia are more likely to suffer falls if they are given anti-depressants by care home staff, a study claims. Many dementia patients also suffer from depression and drugs known as selective serotonin uptake inhibitors (SSRIs) are frequently prescribed. But the British Journal of Clinical Pharmacology reports that the risk of injuries from falls was tripled. The Alzheimer's Society called for more research into alternative treatments. The risk of falls following treatment with older anti-depressants is well established, as the medication can cause side effects such as dizziness and unsteadiness. It had been hoped that a move to newer SSRI-type drugs would reduce this problems, but the latest research, from the Erasmus University Medical Center in Rotterdam, appears to show the reverse. Dr Carolyn Sterke recorded the daily drug use and records of falls in 248 nursing home residents over a two-year period. The average age of the residents was 82, and the records suggested that 152 of them had suffered a total of 683 falls. BBC © 2012

Keyword: Depression; Alzheimers
Link ID: 16272 - Posted: 01.19.2012

By Devin Powell A boa constrictor knows to stop squeezing a juicy rat by sensing the heartbeat of its prey, easing up only when the pulse stops, a new study finds. Detecting heartbeats may give snakes like the boa constrictor an edge for hunting iguanas and other large cold-blooded animals that can cling to life for a long time when cut off from oxygen, researchers report online January 18 in Biology Letters. Taking the pulse of such creatures would be a surefire way to know when to let go. To pinpoint the snake’s sensitivity to this particular vital sign, researchers at Dickinson College in Carlisle, Pa., started with rat corpses lacking any signs of life. The scientists then implanted pressure sensors and artificial hearts, small bulbs pumped with fluid that produce the illusion of a regular pulse. Wild boa constrictors attacked the carcasses with or without the simulated heartbeat. But the snakes hugged harder and for about twice as long when the pulse was switched on. If the pulse stopped, the squeezing also stopped. Lab-raised snakes never exposed to live prey responded the same way, suggesting the behavior is innate, not learned. © Society for Science & the Public 2000 - 2012

Keyword: Evolution
Link ID: 16271 - Posted: 01.19.2012

Heidi Ledford A Scottish intelligence study that began 80 years ago has borne new fruit. Researchers have tracked down the study’s surviving participants — who joined the study when they were 11 years old — to estimate the role that our genes have in maintaining intelligence through to old age. Researchers have long been interested in understanding how cognition changes with age, and why these changes are more rapid in some people than in others. But, in the past, studies of age-related intelligence changes were often performed when the subjects were already elderly. Then, in the late 1990s, research psychologist Ian Deary of the University of Edinburgh, UK, and his colleagues realized that Scotland had two data sets that would allow them to take such studies a step further. In 1932 and 1947, officials had conducted a sweeping study of intelligence among thousands of 11-year-old Scottish children. The data, Deary learned, had been kept confidential for decades. He and his colleagues set about tracking down the original participants, many of whom did not remember taking the original tests. The team collected DNA samples and performed fresh intelligence tests in nearly 2,000 of the original participants, then aged 65 or older. © 2012 Nature Publishing Group,

Keyword: Intelligence; Genes & Behavior
Link ID: 16270 - Posted: 01.19.2012

by Virginia Morell As every dog owner knows, teaching Fido to lie down and be calm can be a giant hurdle in obedience class. Now, it turns out that at least among German Shepherds, genetics play a big role in whether your pet earns a gold star. Researchers gave 104 of the dogs the lie-down-and-be-calm test, and three other behavioral exams, all designed to assess the dogs' ability to control their impulses. Later, the scientists compared the canines' DNA, looking specifically at a gene that is connected to the production of dopamine and norepinephrine. These neurotransmitters are involved in our emotional responses and ability to focus, and have been implicated in humans with attention deficit disorder. The 37 German Shepherds with a shortened version of the gene had the most trouble controlling their impulsive behaviors, regardless of their sex, age, or training. But the dogs with long versions of the gene, such as the one in the photo, passed the impulse-tests with the calm of Zen master. The study, reported in the current issue of PLoS ONE, may not only help breeders identify hyperactive dogs, but could prove useful in studies of ADHD in humans. © 2010 American Association for the Advancement of Science.

Keyword: Genes & Behavior; ADHD
Link ID: 16269 - Posted: 01.19.2012

By JULIA MOSKIN FOR 10 years, wielding slabs of cream cheese and mounds of mayonnaise, Paula Deen has become television’s self-crowned queen of Southern cuisine and one of the country’s most popular chefs, with an empire built on layers of gooey butter cake, fried chicken and sheer force of personality. On Tuesday, she suddenly unveiled a new career for herself: herald of a healthy life. In an interview on the “Today” show on NBC, she revealed — as has long been rumored — that she has Type 2 diabetes, a diagnosis that she said she received three years ago. In an interview with The New York Times, she said the delay in announcing it had been part of a necessary personal journey. “I wanted to wait until I had something to bring to the table,” she said. Now, Ms. Deen, 64, has brought to her own table a multiplatform endorsement deal with Novo Nordisk, the Danish pharmaceutical company that makes Victoza, a noninsulin injectable diabetes medication that she began promoting on Tuesday morning. She and her sons, Jamie and Bobby (who do not have diabetes), are all being paid to spearhead the company’s upbeat new public-relations campaign, “Diabetes in a New Light,” which advocates using the drug along with eating lighter foods and increasing physical activity. All the same, Ms. Deen said she would not change her own lifestyle or cooking style drastically, other than to reduce portion sizes of unhealthful foods. “I’ve always preached moderation,” she said. “I don’t blame myself.” © 2012 The New York Times Company

Keyword: Obesity
Link ID: 16268 - Posted: 01.19.2012

By TARA PARKER-POPE After two decades of steady increases, obesity rates in adults and children in the United States have remained largely unchanged during the past 12 years, a finding that suggests national efforts at promoting healthful eating and exercise are having little effect on the overweight. Over all, 35.7 percent of the adult population and 16.9 percent of children qualify as obese, according to data gathered by the federal Centers for Disease Control and Prevention and published online Tuesday by The Journal of the American Medical Association. While it is good news that the ranks of the obese in America are not growing, the data also point to the intractable nature of weight gain and signal that the country will be dealing with the health consequences of obesity for years to come. “We’re by no means through the epidemic,’’ said Dr. David Ludwig, director of the childhood obesity program at Children’s Hospital in Boston. “Children will be entering adulthood heavier than they’ve ever been at any time in human history. Even without further increases in prevalence, the impact of the epidemic will continue to mount for many years to come.’’ The data come from thousands of men, women and children who have taken part in the National Health and Nutrition Examination Surveys — compiled by the National Center for Health Statistics at the C.D.C. since the 1960s — and represent some of the most reliable statistics available on the health of the American public. The most recent findings are based on data collected from 2009-10 that have been compared with previous surveys collected in two-year cycles beginning in 1999-2000. © 2012 The New York Times Company

Keyword: Obesity
Link ID: 16267 - Posted: 01.19.2012

By Kara Rogers In a study published in late 2011 in Nature, Stanford University geneticist Anne Brunet and colleagues described a series of experiments that caused nematodes raised under the same environmental conditions to experience dramatically different lifespans. Some individuals were exceptionally long-lived, and their descendants, through three generations, also enjoyed long lives. Clearly, the longevity advantage was inherited. And yet, the worms, both short- and long-lived, were genetically identical. This type of finding—an inherited difference that cannot be explained by variations in genes themselves—has become increasingly common, in part because scientists now know that genes are not the only authors of inheritance. There are ghostwriters, too. At first glance, these scribes seem quite ordinary—methyl, acetyl, and phosphoryl groups, clinging to proteins associated with DNA, or sometimes even to DNA itself, looking like freeloaders at best. Their form is far from the elegant tendrils of DNA that make up genes, and they are fleeting, in a sense, erasable, very unlike genes, which have been passed down through generations for millions of years. But they do lurk, and silently, they exert their power, modifying DNA and controlling genes, influencing the chaos of nucleic and amino acids. And it is for this reason that many scientists consider the discovery of these entities in the late 20th century as a turning point in our understanding of heredity, as possibly one of the greatest revolutions in modern biology—the rise of epigenetics. © 2012 Scientific American

Keyword: Development of the Brain; Genes & Behavior
Link ID: 16266 - Posted: 01.19.2012

By Joan Raymond For years, the conventional wisdom was that babies learned how to talk by listening to their parents. But a new study in the Proceedings of the National Academy of Sciences shows that our little angels are using more than their ears to acquire language. They’re using their eyes, too, and are actually pretty good lip readers. The finding could lead to earlier diagnosis and intervention for autism spectrum disorders, estimated, on average, to affect 1 in 110 children in the United States alone. In the study, researchers from Florida Atlantic University tested groups of infants, ranging from four to 12 months of age and a group of adults for comparison. advertisement The babies watched videos of women speaking either in English, the native language used in the home, or in Spanish, a language foreign to them. Using an eye tracker device to study eye movements, the researchers looked at developmental changes in attention to the eyes and mouth. Results showed that at four months of age, babies focused almost solely on the women’s eyes. But by six to eight months of age, when the infants entered the so-called “babbling” stage of language acquisition and reached a milestone of cognitive development in which they can direct their attention to things they find interesting, their focus shifted to the women’s mouths. They continue to “lip read” until about 10 months of age, a point when they finally begin mastering the basic features of their native language. At this point, infants also begin to shift their attention back to the eyes. © 2012 msnbc.com

Keyword: Language; Autism
Link ID: 16265 - Posted: 01.17.2012

By RICHARD A. FRIEDMAN, M.D. In certain quarters of academia, it’s all the rage these days to view human behavior through the lens of evolutionary biology. What survival advantages, researchers ask, may lie hidden in our actions, even in our pathologies? Depression has come in for particular scrutiny. Some evolutionary psychologists think this painful and often disabling disease conceals something positive. Most of us who treat patients vehemently disagree. Consider a patient I saw not long ago, a 30-year-old woman whose husband had had an affair and left her. Within several weeks, she became despondent and socially isolated. She developed insomnia and started to ruminate constantly about what she might have done wrong. An evolutionary psychologist might posit that my patient’s response has a certain logic. After all, she broke off her normal routine, isolated herself and tried to understand her abandonment and plan for the future. You might see a survival advantage in the ability of depressed people like her to rigidly and obsessively fix their attention on one problem, tuning out just about everything and everyone else around them. Certain studies might seem to support this perspective. Paul W. Andrews, a psychologist at Virginia Commonwealth University, reported that normal subjects get sadder while trying to solve a demanding spatial pattern recognition test, suggesting that something about sadness might improve analytical reasoning. © 2012 The New York Times Company

Keyword: Depression; Evolution
Link ID: 16264 - Posted: 01.17.2012

By JANE E. BRODY Hearing loss, a disability currently untreated in about 85 percent of those affected, may be the nation’s most damaging and costly sensory handicap. It is a hidden disability, often not obvious to others or even to those who have it. Its onset is usually insidious, gradually worsening over years and thus easily ignored. Most of those affected can still hear sounds and think the real problem is that people aren’t speaking clearly. They often ask others to speak up, repeat what was said or speak more slowly. Or they pretend they can hear, but their conversations may be filled with non sequiturs. As hearing worsens, they are likely to become increasingly frustrated and socially isolated. Unable to hear well in social settings, they gradually stop going to the theater, movies, places of worship, senior centers or parties or out to restaurants with friends or family. Social isolation, in turn, has been linked to depression and an increased risk of death from conditions like heart disease. And now there is another major risk associated with hearing problems: dementia and Alzheimer’s disease. This finding alone should prompt more people to get their hearing tested and, if found impaired, get properly fitted with aids that can help to keep them cognitively engaged. © 2012 The New York Times Company

Keyword: Hearing; Alzheimers
Link ID: 16263 - Posted: 01.17.2012

By Chelsea Conaboy A. Spinal stenosis is a narrowing of the spinal canal that can - but does not always - cause pain in the legs and other problems. It is typically the result of degenerative effects of aging. Disks or joints in the back may bulge or vertebral bones grow spurs that push into the space where the spinal cord and nerves sit, compressing them. The condition is not uncommon, said Dr. Carol Hartigan, a physiatrist in the Spine Center at New England Baptist Hospital. Researchers using imaging tests have found that as many as 30 percent of people over age 60 may have a narrowed canal, but not all experience symptoms, she said. Especially when the narrowing happens slowly over time, the spinal cord and the nerves can adjust to the change, “like a tree that grows around a fence,’’ she said. But some people will experience pain or weakness in the front or back of their legs, often more severe when they are standing or walking. Some, depending on the location of the stenosis, can have bowel and bladder problems. Hartigan said people should see a doctor if the symptoms persist or if they are interfering with daily activities. Staying physically fit is important to controlling symptoms of stenosis, Hartigan said. Often changing the position of the spine slightly can relieve pain enough to keep moving. Some who have trouble walking, might have an easier time riding a bike or even using a treadmill. Steroid injections can provide temporary relief for some, Hartigan said. © 2012 NY Times Co.

Keyword: Pain & Touch
Link ID: 16262 - Posted: 01.17.2012

By Andrew Newberg Researchers have pinpointed differences between the brains of believers and nonbelievers, but the neural picture is not yet complete. Several studies have revealed that people who practice meditation or have prayed for many years exhibit increased activity and have more brain tissue in their frontal lobes, regions associated with attention and reward, as compared with people who do not meditate or pray. A more recent study revealed that people who have had “born again” experiences have a smaller hippocampus, a part of the brain involved in emotions and memory, than atheists do. These findings, however, are difficult to interpret because they do not clarify whether having larger frontal lobes or a smaller hippocampus causes a person to become more religious or whether being pious triggers changes in these brain regions. Various experiments have also tried to elucidate whether believing in God causes similar brain changes as believing in something else. The results, so far, show that thinking about God may activate the same parts of the brain as thinking about an airplane, a friend or a lamppost. For instance, one study showed that when religious people prayed to God, they used some of the same areas of the brain as when they talked to an average Joe. In other words, in the religious person’s brain, God is just as real as any object or person. © 2012 Scientific American,

Keyword: Emotions; Brain imaging
Link ID: 16261 - Posted: 01.17.2012

By Dwayne Godwin and Jorge Cham © 2012 Scientific American

Keyword: Hearing
Link ID: 16260 - Posted: 01.16.2012

By Maria Konnikova What if every visit to the museum was the equivalent of spending time at the philharmonic? For painter Wassily Kandinsky, that was the experience of painting: colors triggered sounds. Now a study from the University of California, San Diego, suggests that we are all born synesthetes like Kandinsky, with senses so joined that stimulating one reliably stimulates another. The work, published in the August issue of Psychological Science, has become the first experimental confir­mation of the infant-synesthesia hy­pothesis—which has existed, unproved, for almost 20 years. Researchers presented infantsand adults with images of repeating shapes (either circles or triangles) on a split-color background: one side was red or blue, and the other side was yellow or green. If the infants had shape-color asso­ciations, the scientists hypoth­esized, the shapes would affect their color preferences. For in­stance, some infants might look significantly longer at a green back­ground with circles than at the same green background with triangles. Absent synesthesia, no such dif­ference would be visible. The study confirmed this hunch. Infants who were two and three months old showed significant shape-color associations. By eight months the preference was no longer pronounced, and in adults it was gone altogether. © 2012 Scientific American

Keyword: Development of the Brain
Link ID: 16259 - Posted: 01.16.2012

By NICHOLAS BAKALAR Drinking alcohol causes a pleasant feeling because it releases endorphins, the brain’s natural opioids. But a new study has found that problem drinkers differ from social drinkers in the way alcohol affects one part of the brain. The report appeared Wednesday in Science Translational Medicine. Researchers performed PET imaging on 13 heavy drinkers and 12 social drinkers after each had had a standardized amount of alcohol. The scientists traced the release of endorphins in two regions of the brain — the nucleus accumbens and the orbitofrontal cortex — and recorded the volunteers’ subjective feelings of intoxication. All subjects reported feelings of intoxication as the researchers observed changes in opioid release in the nucleus accumbens. There was no difference between heavy drinkers and the control group when it came to changes in blood alcohol levels over time. But with the heavy drinkers, unlike with the healthy controls, there was a positive correlation between the release of endorphins in the orbitofrontal cortex and the subjects’ subjective feeling of drunkenness. This phenomenon, the authors write, may contribute to an increased perception of pleasure and to excessive alcohol consumption in these drinkers. © 2012 The New York Times Company

Keyword: Drug Abuse
Link ID: 16258 - Posted: 01.16.2012

By Janet Raloff A new study may explain how rising carbon dioxide concentrations — and the ocean acidification they induce — can cause topsy-turvy changes in the behavior of fish. Like a flipped switch, the normal response of nerve cells can reverse as acidifying seawater perturbs how a fish regulates acids and bases in its body, including the brain. “This could be a big deal,” says neurobiologist Andrew Dittman of the National Oceanic and Atmospheric Administration’s Northwest Fisheries Science Center in Seattle. Dittman, who was not affiliated with the study, says the new findings could go a long way toward explaining curious sensory changes observed in fish exposed to acidifying waters. The scary scent of predators, for example, can suddenly become alluring. For the new study, published online January 15 in Nature Climate Change, Göran Nilsson of the University of Oslo and his colleagues homed in on brain chemistry. The idea emerged after Philip Munday of James Cook University in Townsville, Australia, told Nilsson of behavioral quirks his laboratory fish were exhibiting in a high–carbon dioxide environment — conditions exemplifying ocean waters a half-century or more from now. Nilsson, a neurophysiologist, speculated that a connection between nerves and chemistry might be involved. “It was very much an ‘Aha’ moment,” Munday says. © Society for Science & the Public 2000 - 2012

Keyword: Drug Abuse
Link ID: 16257 - Posted: 01.16.2012

By DIANE ACKERMAN WHAT’S the quickest way to a man’s heart? No, not through the chest wall with a knife. According to Mom wisdom, it’s a cozy meal, in a penumbra of pleasure that mingles the fragrant food with the cook. If men are anything like common fruit flies — and who’s to say they’re not at times; heaven knows women are — Mom was right. Anyway, that’s the romantic ploy of female fruit flies, for whom a dinner date is the ultimate rush. And rush it literally is, since they live only about 25 days and can’t afford to be shy. Still, the males need to be in the right mood, and the females are surprisingly picky and manipulative, given their short careers. Did I mention that some fruit flies have come-hither eyes? I don’t mean the dozens of mosaic facets, so evocative of hippie sunglasses, but the zingy psychedelic eye colors lab folk like to breed into them, the better to study mutant genes. As a Cornell grad student, I often stopped by the fetid biology lab to admire the eggplant-blackness of the abdomens, the spiky hairs, the gaudy prisms of the eyes — some apricot, some teal, some purple, some the brick-red of Ming vases. A favorite of biologists, fruit flies have it all — they’re prowling for mates within 12 hours of birth, they’re easy to raise and they can lay 100 eggs a day. Plus, they share most of our genes, including about 70 percent of those we’ve linked to such diseases as Parkinson’s and Alzheimer’s. © 2012 The New York Times Company

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 16256 - Posted: 01.16.2012

By NICHOLAS BAKALAR A new study has found that among immigrants, younger age at the time of migration predicts a higher incidence of psychotic disorders. The study, published in December in The American Journal of Psychiatry, was conducted from 1997 to 2005 in The Hague, where there are detailed records on almost everyone ages 15 to 54 who has made contact with the health care system for a possible psychotic disorder. The researchers found 273 immigrants, 119 second-generation citizens and 226 Dutch citizens who fit the criteria. In four ethnic groups — people from Suriname, the Netherlands Antilles, Turkey and Morocco — the risk of psychosis was most elevated among those who immigrated before age 4. There was no association of psychosis with age among immigrants from Western countries. The researchers, led by Dr. Wim Veling of the Parnassia Psychiatric Institute in The Hague, investigated various possible explanations — that social factors may be involved, that people may migrate because they are prone to psychosis, that a decision to migrate is influenced by the early appearance of psychosis, among many others. But the correlation between younger age of migration and the development of psychosis persisted. “We don’t know the reason,” said Dr. Ezra Susser, the senior author and a professor of epidemiology at Columbia University, “but it might be related to early social context, which we know has an important influence on later health and mental health.” © 2012 The New York Times Company

Keyword: Schizophrenia; Development of the Brain
Link ID: 16255 - Posted: 01.14.2012