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By Carrie Arnold Put on a pair of headphones and turn up the volume so that you can’t even hear yourself speak. For those who stutter, this is when the magic happens. Without the ability to hear their own voice, people with this speech impediment no longer stumble over their words—as was recently portrayed in the movie The King’s Speech. This simple trick works because of the unusual way the brain of people who stutter is organized—a neural setup that affects other actions besides speech, according to a new study. Normal speech requires the brain to control movement of the mouth and vocal chords using the sound of the speaker’s own voice as a guide. This integration of movement and hearing typically happens in the brain’s left hemisphere, in a region of the brain known as the premotor cortex. In those who stutter, however, the process occurs in the right hemisphere—probably because of a slight defect on the left side, according to past brain-imaging studies. Singing requires a similar integration of aural input and motor control, but the processing typically occurs in the right hemisphere, which may explain why those who stutter can sing as well as anyone else. (In a related vein, The King’s Speech also mentioned the common belief that people who stutter are often left-handed, but studies have found no such link.) In the new study, published in the September issue of Cortex, researchers found that the unusual neural organization underlying a stutter also includes motor tasks completely unrelated to speech. A group of 30 adults, half of whom stuttered and half of whom did not, tapped a finger in time to a metronome. When the scientists interfered with the function of their left hemisphere using transcranial magnetic stimulation, a noninvasive technique that temporarily dampens brain activity, nonstutterers found themselves unable to tap in time—but those who stuttered were unaffected. When the researchers interfered with the right hemisphere, the results were reversed: the stuttering group was impaired, and the nonstutterers were fine. © 2012 Scientific American,
Keyword: Language; Attention
Link ID: 16289 - Posted: 01.24.2012
by Greg Miller Drugs like psilocybin, the active ingredient in hallucinogenic mushrooms, play all sorts of tricks on the mind. They distort the perception of time, space, and self, and even untether the senses. Some researchers thought these strange effects might result from the drugs overexciting the brain. But the first study to use functional magnetic resonance imaging (fMRI) to examine brain activity in people who've taken psilocybin finds that the drug reduces neural firing in key communication hubs, essentially disconnecting some brain regions from each other. In Central America and elsewhere, hallucinogenic drugs have been used for centuries in healing and religious ceremonies. Recent years have seen renewed interest in exploiting them to explore the neural basis of spirituality and potentially to treat depression, anxiety, and other mental illnesses. Yet neuroscientists know little about how these compounds act on the brain to cause such intensely altered experiences. Hallucinogenic drugs are tightly regulated, and few previous studies have tried to gauge their effects on the human brain. One study, using positron emission tomography (PET), found that psilocybin increases brain metabolism, especially in the frontal cortex. In the new work, published this week in the Proceedings of the National Academy of Sciences, researchers led by psychopharmacologists Robin Carhart-Harris and David Nutt of Imperial College London used a different method, fMRI, to scan the brains of 30 people who were under the influence of psilocybin. The tight confines and loud noises of the scanner could be scary for someone on psilocybin, Nutt says. To minimize the chances of anyone having a bad trip, the researchers recruited people who'd taken hallucinogens previously, and they delivered the drug intravenously so that it would have a faster—and shorter—effect than, say, eating magic mushrooms. © 2010 American Association for the Advancement of Science
Keyword: Drug Abuse
Link ID: 16288 - Posted: 01.24.2012
By Nathan Seppa Competing in vain for the attention of someone special or fretting over a mid-term exam may not be healthy. Such stress seems to boost a person’s supply of two proteins that cause inflammation, researchers report January 23 in the Proceedings of the National Academy of Sciences. These inflammatory triggers have been linked to an increased risk of heart disease, high blood pressure, cancer and depression. The new results add to a growing body of research that links social stress with biological risks. “We wanted to see how mental states such as optimism, or social relationships such as competition, get under the skin,” says study coauthor Shelley Taylor, a social neuroscientist at the UCLA School of Medicine. She and her colleagues looked at the relationship between day-to-day stress and two proteins that trigger inflammation in the body, called pro-inflammatory cytokines. The researchers asked 122 young, healthy adults to keep a diary of all positive and negative social interactions for eight days, as well as descriptions of any incidents that involved competition. “We picked young adults with no history of heart disease or inflammation disorders or depression [because] we wanted to look at the biological processes in a population that was healthy,” Taylor says. © Society for Science & the Public 2000 - 2012
Keyword: Stress
Link ID: 16287 - Posted: 01.24.2012
Katharine Sanderson An uncharted trawl through thousands of small molecules involved in the body's metabolism may have uncovered a potential route to treating pain caused by nerve damage. Neuropathic pain is a widespread and distressing condition, and is notoriously difficult to treat. So Gary Siuzdak, a chemist and molecular biologist at the Scripps Research Institute in La Jolla, California, and his team decided to take an unusual route to finding a therapy. Their results are published today in Nature Chemical Biology1. They took rats with surgically damaged paws, who were consequently suffering from neuropathic pain, and instead of analysing changes in gene expression and proteins in the animals, focused on metabolites – the biochemical intermediates and end-products of bodily processes such as respiration and the synthesis and breakdown of molecules. The science that looks at the body's metabolite composition is known as metabolomics. Using mass spectrometry, which can detect many different chemicals simultaneously, the researchers were able to identify the metabolites present in these animals 21 days after surgery. The team analysed samples of the injured rats’ blood plasma, of tissue near the injured paw, and of tissue from different areas of the spinal column, and compared the metabolites present with that of the same site in healthy rats. One particular area differed markedly between the two cases: the dorsal horn in the spinal column. © 2012 Nature Publishing Group,
Keyword: Pain & Touch
Link ID: 16286 - Posted: 01.23.2012
By JOSEPH LEDOUX You are taking a walk in the woods ― pleasant, invigorating, the sun shining through the leaves. Suddenly, a rattlesnake appears at your feet. You experience something at that moment. You freeze, your heart rate shoots up and you begin to sweat ― a quick, automatic sequence of physical reactions. That reaction is fear. A week later, you are taking the same walk again. Sunshine, pleasure, but no rattlesnake. Still, you are worried that you will encounter one. The experience of walking through the woods is fraught with worry. You are anxious. This simple distinction between anxiety and fear is an important one in the task of defining and treating of anxiety disorders, which affect many millions of people and account for more visits to mental health professionals each year than any of the other broad categories of psychiatric disorders. Scientists generally define fear as a negative emotional state triggered by the presence of a stimulus (the snake) that has the potential to cause harm, and anxiety as a negative emotional state in which the threat is not present but anticipated. We sometimes confuse the two: When someone says he is afraid he will fail an exam or get caught stealing or cheating, he should, by the definitions above, be saying he is anxious instead. © 2012 The New York Times Company
Keyword: Emotions; Stress
Link ID: 16285 - Posted: 01.23.2012
Analysis by Jennifer Viegas Humans are often obsessed with their weight, but nature seems to know exactly how fat each animal on the planet should be. The perfect weight depends on how each species solves the problem of avoiding both starving to death and being killed by predators, new research suggests. The study, published in The American Naturalist, explains how these causes of death often exert opposite pressures on animals. Storing a lot of fat, for example, helps animals survive periods without food but also slows their running speeds and so makes getting caught by a predator more likely. Animals can be stronger to compensate, but the energetic costs of extra muscle mean that the animal would starve more quickly during a food shortage. Andrew Higginson of Bristol University's School of Biological Sciences led the study, which used mathematical models to explore how much muscle and fat animals should have in their body to give themselves the best chances of survival. An important consideration was how much carrying fat increases the energetic costs of movement. The models revealed that the size of this cost influenced whether larger animals should have more fat than smaller animals, or vice versa. "Our results explain differences between different families of mammal. For example, larger bats carry proportionally less fat than small bats but larger carnivores carry more fat than small carnivores. Among rodents, it's the medium-sized species that carry around the most fat!" Higginson said in a press release. © 2012 Discovery Communications, LLC.
Keyword: Obesity; Evolution
Link ID: 16284 - Posted: 01.23.2012
Erin Allday, Chronicle Staff Writer Greg Moulton was getting ready for work one morning in 2006 when he suddenly lost all of the strength in his right arm, and he realized he was having a stroke. Thinking fast, he called his wife and left a message for her. Then he called his office to let his boss know that he was having a stroke and "would be in shortly," Moulton said. "I was very naive," said Moulton, 51, last week from his home in Fremont. "I knew what a stroke was, but I didn't know how serious it was." Fortunately for Moulton, his wife did know, and so did the paramedics who arrived at his home a few minutes later. Another lucky turn: Alameda County had just started a new emergency stroke response system, which meant that everyone from the 911 dispatcher Moulton's wife called to the emergency room doctors and nurses at the hospital where he was taken were ready for him and knew immediately how to treat him. Such stroke systems have been popping up all over California in the past six years, and there are now 11 regions in the state - including Alameda, Contra Costa, Santa Clara and San Mateo counties in the Bay Area - that provide coordinated emergency stroke care. Contra Costa was the most recent county to start a system, which launched earlier this month. © 2012 Hearst Communications Inc.
Keyword: Stroke
Link ID: 16283 - Posted: 01.23.2012
A suburban Chicago man accidentally shot a 3.25in (8.25cm) nail into his skull but is recovering after doctors successfully removed it from the centre of his brain. Dante Autullo, 34, was in his workshop when a nail gun recoiled near his head. But he had no idea the nail had entered his brain until the next day, when he began feeling nauseous. Doctors told Mr Autullo that the nail came within millimetres of the area used for motor function. His fiancee, Gail Glaenzer, told the Associated Press on Friday that he was in good spirits after the two-hour surgery to remove the nail at Advocate Christ Medical Center in Oak Lawn, Illinois. "He feels good. He moved all his limbs, he's talking normal, he remembers everything," she said. "It's amazing, a miracle." Ms Glaenzer said she had no idea the nail had entered his skull when she cleaned a cut on his forehead. BBC © 2012
Keyword: Miscellaneous
Link ID: 16282 - Posted: 01.23.2012
By Laura Sanders A night of shut-eye sears bad feelings into the brain, while waking hours take the emotional edge off, a new study finds. Though preliminary and somewhat inconsistent with earlier research, the results suggest that staying awake after something awful happens might be a way to blunt the emotional fallout of traumatic experiences, researchers report in the Jan. 18 Journal of Neuroscience. Sleep is known to lock in memories, particularly emotional ones, but scientists didn’t know whether accompanying feelings are locked in, too — a question that’s particularly relevant to people who suffer from post-traumatic stress disorder. “If we really want to know if this is relevant to trauma survivors, then we need to know if sleep not just changes the memory, but if it changes how you feel about it if you experience it again,” says study coauthor Rebecca Spencer of the University of Massachusetts Amherst. In the study, Spencer and her colleagues showed pictures of neutral scenes, such as a street, or negative scenes, such as an upsetting car crash, to 106 young adults. Participants then rated the emotion inspired by the image on a one-to-nine scale ranging from sad to happy. Afterward, participants were either sent to bed for a full night’s sleep or asked to stay awake for 12 hours. Then the researchers retested the participants by showing some of the same pictures mixed in with new images. As expected, the people who slept were better at remembering which images they had seen the day before. But the memory wasn’t the only thing that stuck around: Sleepers held on tighter to their feelings, while the sadness scores given by people who stayed awake tended to be weaker in the second session. © Society for Science & the Public 2000 - 2012
by Sara Reardon Péos, Mininos, Cécil, Teha, and Amtan are performing dolphins at the Planète Sauvage dolphinarium in Port-Saint-Père, France. Every day, as music and sounds of the sea play in the background, they show off their swimming, jumping, and ball-catching skills for an adoring audience and squawk and whistle just like dolphins should. But at night, they make strange noises that researchers believe are imitations of humpback whale songs included in the performance soundtrack. If so, the identification of this unexpected repertoire would mark the first time that dolphins have been heard to rehearse new sounds hours after hearing them rather than right away, providing insights into how they store and process memories. Researchers discovered the dolphins' midnight melodies by accident. Ethologist Martine Hausberger of the University of Rennes 1 in France and her colleagues had hung underwater microphones in the tank because little is known about what dolphins sound like at night. One night, they suddenly heard 25 new sounds (see below) that the dolphins had never made before, although they weren't sure which of the five animals was talking. Because dolphins are known for mimicry, the researchers examined their complex daytime environment to determine where the noises might be coming from. They finally zeroed in on the new soundtrack that Planète Sauvage was playing during performances, which included music, sea gulls' calls, the dolphins' own whistles, and humpback whale calls. When the researchers used a computer program to compare auditory recordings of the whale calls with the mysterious nighttime noises, it showed that the two sounds were very similar. And because the dolphins had been captive their entire lives, they couldn't have picked them up from real whales. © 2010 American Association for the Advancement of Science.
Keyword: Animal Communication; Sleep
Link ID: 16280 - Posted: 01.21.2012
by Linda Geddes Schizophrenia could be a profound form of jetlag in which the brain's central clock runs out of kilter with peripheral clocks around the rest of the body. People with the illness often complain of sleeping difficulties, and last month a study of 20 people with schizophrenia confirmed that sleep disruption is common and not down to their medication or lifestyle (British Journal of Psychiatry), DOI: 10.1192/bjp.bp.111.096321). Now we may be closer to understanding why: a genetic mutation that triggers schizophrenia-like symptoms in mice also appears to disrupt their circadian rhythm or body clock. Russell Foster at the University of Oxford and his colleagues had been puzzling over the link between sleep disturbances and mental illness. So they investigated circadian patterns in mice with a defect in the SNAP25 gene, often used as an animal model to study the illness. SNAP25 has also been associated with schizophrenia in humans. When the mice were kept under a schedule of 12 hours of light followed by 12 hours of darkness, they were active when you would normally expect mice to be sleeping, suggesting that their circadian rhythms were disrupted. © Copyright Reed Business Information Ltd.
Keyword: Schizophrenia; Biological Rhythms
Link ID: 16279 - Posted: 01.21.2012
By BENEDICT CAREY Proposed changes in the definition of autism would sharply reduce the skyrocketing rate at which the disorder is diagnosed and might make it harder for many people who would no longer meet the criteria to get health, educational and social services, a new analysis suggests. The definition is now being reassessed by an expert panel appointed by the American Psychiatric Association, which is completing work on the fifth edition of its Diagnostic and Statistical Manual of Mental Disorders, the first major revision in 17 years. The D.S.M., as the manual is known, is the standard reference for mental disorders, driving research, treatment and insurance decisions. Most experts expect that the new manual will narrow the criteria for autism; the question is how sharply. The results of the new analysis are preliminary, but they offer the most drastic estimate of how tightening the criteria for autism could affect the rate of diagnosis. For years, many experts have privately contended that the vagueness of the current criteria for autism and related disorders like Asperger syndrome was contributing to the increase in the rate of diagnoses — which has ballooned to one child in 100, according to some estimates. The psychiatrists’ association is wrestling with one of the most agonizing questions in mental health — where to draw the line between unusual and abnormal — and its decisions are sure to be wrenching for some families. At a time when school budgets for special education are stretched, the new diagnosis could herald more pitched battles. © 2012 The New York Times Company
Keyword: Autism
Link ID: 16278 - Posted: 01.21.2012
Sean O'Neill, contributor Sue Savage-Rumbaugh is a primatologist who works at the Great Ape Trust in Des Moines, Iowa, where she explores the mental and linguistic skills of our primate cousins. As a graduate, you were all set to do a postdoc in psychology at Harvard University. What happened? Yes, I was due to go to Harvard to work with behaviourist B. F. Skinner and his famous pigeons. But before I left I happened to sit in on a class by primate researcher Roger Fouts, who brought a chimpanzee named Booee to class. Roger held up objects like a hat, a key and a pair of shoes, and Booee would make what Roger said were signs for those objects. I saw a chimpanzee doing what seemed to be a symbolic task and I was hooked. I said to myself: "Wait a minute, people are teaching chimpanzees human language, and I'm going to Harvard to study pigeons? You need to stay here, this is where it's at if you are interested in the origins of the human mind." I have worked with apes ever since. Your work on the linguistic capabilities of apes has taken you into uncharted territory... Yes, for better or for worse, I have gone to a place that other researchers have not. If I had had any inkling into the huge degree of linguistic, conceptual and social similarity between ourselves and bonobos when I started the work I would have been scared to death to do it. © Copyright Reed Business Information Ltd.
Keyword: Language; Evolution
Link ID: 16277 - Posted: 01.21.2012
By ABIGAIL SULLIVAN MOORE IN their undergrad uniforms of fleece and sweats, a clutch of Rutgers students gathered on the worn red couches of their dorm’s common room and told their stories. A good-looking, fun-loving 23-year-old named Greg described arriving at college freshman year with a daily pot-smoking habit and a close relationship with alcohol. He soon followed the lead of his alcoholic father and was binge drinking (five drinks or more in a row). “It was pretty scary,” he said. For his self-diagnosed anxiety and depression, he secretly began taking Klonopin, which he bought from another student. By sophomore year, he was taking six a day. And when it ran out, he wound up in a hospital to manage withdrawal, followed by nine months of rehab. Unlike the other students on the couch, Devin Fox, 26, gave permission to use his surname because of his career choice. He is pursuing a graduate degree in social work, hoping to work at a policy level in the mental illness field. Mr. Fox had been so despondent over his addiction to methamphetamine that he tried to overdose. Like Greg, he is now three years clean. The students live in one of two recovery dorms tucked away in anonymity on the sprawling New Brunswick, N.J., campus. In 1988, Rutgers started what is believed to be the first residential recovery program on a college campus, according to Lisa Laitman, director of its Alcohol and Other Drug Assistance Program. She helped create the program after seeing students struggle to abstain as dorm-mates partied. © 2012 The New York Times Company
Keyword: Drug Abuse
Link ID: 16276 - Posted: 01.21.2012
Caitlin Stier, video intern Want to freeze an object using the power of your mind? Watch the spinning objects in this video and they will suddenly appear to stop moving. However, they never actually freeze and are constantly turning at a steady rate. The illusion, created by researcher Max Dürsteler from University Hospital Zurich, uses a swaying background to trick our perception. When it rotates faster than the object in the foreground, and in the same direction, the object seems to slow down. But when the background moves in the opposite direction, the figure in the middle appears to speed up. In the first two examples, the background is distinct from the image on top of it. But in a third clip, the rotating figure blends in with the background, making the illusion more pronounced. In a final example, where background and foreground are contrasting once again, the backdrop rotates at a constant rate while the central figure sways back and forth. With this role reversal, the illusion is lost. While researchers are still investigating how this illusion works, Dürsteler suspects that our brain has a bias towards seeing objects as stationary. Motion is usually perceived in one of three states: either in or out of sync with its surroundings or stationary in relation to the observer The brain trick won the Best Illusion of the Year contest in 2006. © Copyright Reed Business Information Ltd.
Keyword: Vision
Link ID: 16275 - Posted: 01.21.2012
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


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