By INGFEI CHEN Scientists have begun to pull back the veil of mystery that has surrounded narcolepsy since it was first described more than 125 years ago. In 2000, investigators reported that a lack of a neurochemical called hypocretin is a prime culprit in the sleep disorder. Patients with classic narcolepsy — a combination of irresistible sleepiness and sudden collapses from muscle weakness — are missing most of the brain cells that make the wakefulness-promoting protein. But high expectations for a therapeutic payoff have since flagged. While narcoleptic patients have gained two helpful new medications in the last decade, they are still waiting for a cure to correct their hypocretin deficiency. Meanwhile, researchers remain flummoxed by the underlying question: What destroys the hypocretin-producing neurons in the first place? “A few years ago we were all sort of proudly crowing about how now we knew what was happening in narcolepsy,” said Dr. Thomas Scammell, a neurologist at Harvard Medical School. “And yeah, now we know what the cellular abnormality is, but we still don’t know what causes it.” As a result, he said, “we can’t stop or reverse the cell loss.” Copyright 2008 The New York Times Company

Keyword: Narcolepsy
Link ID: 11337 - Posted: 06.24.2010

Brain scans have revealed a possible biological basis for cocaine addiction which may explain why some get hooked, while others can use the drug socially. The scans show cocaine alters parts of the brain controlling behaviour and appropriate decision-making. In effect, the drug messes with what is colloquially known as willpower - with some maybe more vulnerable than others. Trinity College Dublin researchers will present their findings to a Royal Society meeting. The researchers took brain scans of cocaine users while they performed computer tasks. They found that cocaine increased activity in areas of the pre-frontal cortex. The scans also revealed differences in brain structures of cocaine users. It is unclear whether the differences existed before they started taking cocaine, or were a result of using the drug. But the findings raise the possibility that differences in brain structure render some people potentially more vulnerable to the effects of the drug. Lead researcher Dr Hugh Garavan said previous research into drug abuse had tended to focus on the emotional aspects of addictions - such as pleasure seeking, craving and withdrawal. The latest study suggests that it is not simply these emotions that are affected by cocaine, but the way the brain deals with them, and keeps them in check by controlling a person's actions. He said: "This research helps us move away from thinking of drug dependence as a moral weakness and allows us to see it as more of a medical condition. "Understanding the role that our brain plays in addiction may also have important implications for treating long-term addiction and designing intervention therapies. (C)BBC

Keyword: Drug Abuse
Link ID: 11336 - Posted: 02.26.2008

By JANE E. BRODY Josh Swiller was 22 and profoundly deaf when he applied to the Peace Corps in search of adventure. And indeed, adventure he found. His experiences in Zambia are eloquently recounted in his hard-to-put-down memoir of deafness and Africa, “The Unheard” (Holt, 2007). But how could someone so hard of hearing get into the Peace Corps, let alone learn a foreign language and communicate in it? Mr. Swiller told me he had no problem with the interview, which was conducted one-on-one in a quiet room, enabling him to hear and to read lips. Through the devoted efforts of an audiologist and his mother, he could speak nearly as well as a normal-hearing person. And he did not have a problem learning the language of Zambia. “I was so used to paying close attention when other people spoke,” Mr. Swiller recalled in an interview. “I was used to asking people to repeat themselves.” He added: “Being deaf and having three brothers, one of whom is also deaf, I learned how to communicate without language. I could conduct conversations when I understood only a few words in each sentence.” That was remarkable in itself. But far more remarkable is that the interview with me was conducted over the telephone, something Mr. Swiller, 37, could not have done three years ago. In 2005, he and his brother underwent life-changing surgery, substituting a cochlear implant for the hearing aids that were no longer working for them. Copyright 2008 The New York Times Company

Keyword: Hearing
Link ID: 11335 - Posted: 06.24.2010

New generation anti-depressants have little clinical benefit for most patients, research suggests. A University of Hull team concluded the drugs actively help only a small group of the most severely depressed. Marjorie Wallace, head of the mental health charity Sane, said that if these results were confirmed they could be "very disturbing". But the makers of Prozac and Seroxat, two of the commonest anti-depressants, said they disagreed with the findings. A spokesman for GlaxoSmithKline, which makes Seroxat, said the study only looked at a "small subset of the total data available". And Eli Lilly, which makes Prozac, said that "extensive scientific and medical experience has demonstrated it is an effective anti-depressant". Patients are advised not to stop taking their medication without first consulting a doctor. The researchers accept many people believe the drugs do work for them, but argue that could be a placebo effect - people feel better simply because they are taking a medication which they think will help them. In total, the Hull team, who published their findings in the journal PLoS Medicine, reviewed data on 47 clinical trials. They reviewed published clinical trial data, and unpublished data secured under Freedom of Information legislation. They focused on drugs which work by increasing levels of the mood controlling chemical serotonin in the brain. These included fluoxetine (Prozac) and paroxetine (Seroxat), from the class known as Selective Serotonin Reuptake Inhibitors (SSRIs), alongside another similar drug called venlafaxine (Efexor) - all commonly prescribed in the UK. The number of prescriptions for anti-depressants hit a record high of more than 31 million in England in 2006 - even though official guidance stresses they should not be a first line treatment for mild depression. There were 16.2m prescriptions for SSRIs alone. The researchers found that even the positive effects seen on severely depressed patients were relatively small, and open to interpretation. (C)BBC

Keyword: Depression
Link ID: 11334 - Posted: 02.26.2008

By Steve Mitchell A blood test could be used to diagnose and assess the severity of certain mental illnesses, such as bipolar disorder, according to a new study. But some experts think this raises ethical concerns about prying into a person's mental status. Lab tests that can accurately detect mental illnesses have long been considered the “Holy Grail” of psychiatry. Currently, bipolar disorder and other conditions such as depression are diagnosed based on the patient's description of their symptoms and the physician's judgment, sometimes making it difficult to get an accurate diagnosis or determine the severity of a patient's condition. But now researchers have shown that 10 genes that can be detected in the blood could provide a better way to assess a patient. “Patients aren’t sure how ill they really are, and neither is the clinician — sometimes dismissing their symptoms, sometimes overestimating them,” said Dr. Alexander Niculescu, III, a psychiatrist at the Indiana University School of Medicine in Indianapolis, who led the research published Tuesday by the journal Molecular Psychiatry. “Having an objective test for disease state, disease severity, and especially to measure response to treatment, would be a big step forward.” More work remains to be done to confirm these findings, Niculescu said, adding that tests could hit the market in as little as five years. © 2008 MSNBC Interactive

Keyword: Schizophrenia; Depression
Link ID: 11333 - Posted: 06.24.2010

Anna Petherick Adolescents with larger amygdalas are more likely to have long and moody interactions with their mothers.BananastockA study of Australian adolescents has identified changes in the brain that correlate with the normal grumbling aggression and moodiness often seen in this age group. The study finds similar patterns in the relative sizes of parts of the brain of whining adolescents as has been seen in young adults with more serious behavioural problems. But the extent to which adolescent biology will determine a child’s behaviour later in life, or how much other factors might counter this, are not yet known. Nicholas Allen of the University of Melbourne in Australia and his colleagues looked at the parent-child interactions of 137 young people, and linked patterns in the adolescents’ behaviour to the sizes of various structures in their brains. “Neuroimaging research is more often done on people with mental diseases or the results are correlated with performance on psychometric tests,” says Allen. “Only rarely is it used to investigate day-to-day behaviours.” © 2008 Nature Publishing Group

Keyword: Development of the Brain; Aggression
Link ID: 11332 - Posted: 06.24.2010

Campaigners are calling for social networking websites, such as Facebook and MySpace, to clamp down on pro-anorexia sites. Doctors at one of the country's largest eating disorders treatment centres said they needed to act more responsibly. The eating disorders charity, B-eat, said little progress had been made on combating "pro-ana" sites. The networking sites said it was hard to distinguish between support groups and "pro-anorexia" groups. But a spokesperson for MySpace said they were working with organisations such as B-eat. Over 1.1 million Britons are known to suffer from an eating disorder. The vast majority are women, although experts believe the numbers could actually be much higher as many cases go undiagnosed. Specialists and charities say the rise of the internet and new media has played a significant part in providing easier access to information on how to get thin. Research has shown that young women exposed to pro-ana websites felt more negative, had lower self-esteem, perceived themselves as heavier and were more likely to compare their bodies with other women. Dr Ty Glover, consultant psychiatrist on the Eating Disorders Unit at Cheadle Royal Hospital, said it had proven difficult to shut down pro-ana websites, but the situation was slightly different for sites such as Facebook. "Social networking sites can censor their material and we expect them to act responsibly," he said. Rather than censor these groups, we are working to create partnership (C)BBC

Keyword: Anorexia & Bulimia
Link ID: 11331 - Posted: 02.25.2008

By ALEX BERENSON NORTH WALES, Pa. — SCIENTISTS who develop drugs are familiar with disappointment — brilliant theories that don’t pan out or promising compounds derailed by unexpected side effects. They are accustomed to small steps and wrong turns, to failure after failure — until, in a moment, with hard work, brainpower and a lot of luck, all those little failures turn into one big success. For Darryle D. Schoepp, that moment came one evening in October 2006, while he was seated at his desk in Indianapolis. At the time, he was overseeing early-stage neuroscience research at Eli Lilly & Company and colleagues had just given him the results from a human trial of a new schizophrenia drug that worked differently than all other treatments. From the start, their work had been a long shot. Schizophrenia is notoriously difficult to treat, and Lilly’s drug — known only as LY2140023 — relied on a promising but unproved theory about how to combat the disorder. When Dr. Schoepp saw the results, he leapt up in excitement. The drug had reduced schizophrenic symptoms, validating the efforts of hundreds of scientists, inside and outside of Lilly, who had labored together for almost two decades trying to unravel the disorder’s biological underpinnings. Copyright 2008 The New York Times Company

Keyword: Schizophrenia
Link ID: 11330 - Posted: 06.24.2010

By Jeneen Interlandi Annie Fuller knew she was in trouble a year ago, when in the space of a few hours she managed to drink a male co-worker more than twice her size under the table. Of course, she'd been practicing for a quarter of her life by then; at 47, she was pouring a pint of bourbon, a 12-pack of beer and a couple of bottles of wine into her 115-pound body each day. She had come to prefer alcohol to food, sex or the company of friends and loved ones. Her marriage had ended; she had virtually stopped leaving the house, except to work and to drink. Fuller had tried and failed enough times over the years to know that she would not be able to sober up on her own. The last time she'd stopped drinking her body went into violent seizures, a common and terrifying symptom of alcohol withdrawal. But the single mother and mortgage-company VP refused to sign into rehab. "I live in a small town," she says. "And when you go to a hospital for something like that, everybody knows about it." So when a family doctor told her about Vivitrol, a monthly injection that prevents patients from drinking alcohol by obliterating its ability to intoxicate, Fuller agreed. She took a sabbatical from work, sent her 15-year-old daughter to stay with relatives and hunkered down to weather the painful, frightening blizzard of detoxification in the comfort of her own living room. What does it mean to be an addict? For a long time the answer was that someone like Fuller "lacked willpower," a tautology that is pretty much useless as a guide to treatment. In the current jargon of the recovery movement, addiction to alcohol, drugs or nicotine is a "bio-psycho-social-spiritual disorder," a phrase that seems to have been invented by the treatment industry to emphasize how complex the problem is and how much more funding it deserves. But the word itself comes from the Latin addictus, a debtor who was indentured to work off what he owed; someone addicted to alcohol or drugs is powerless over his or her fate in the same way—except debtors-as-addicts can never fully balance the books. © 2008 Newsweek, Inc.

Keyword: Drug Abuse
Link ID: 11329 - Posted: 06.24.2010

Mike Marshall As part of our special issue on music, Daniel Levitin has written The Music Illusion, which looks at auditory illusions and how they can help us understand the workings of the human brain. Here we have compiled five of the most striking auditory illusions discovered so far. We had a big pool to choose from, from the mysterious quintina (fifth voice) heard in some types of throat-singing, to the saxophone solo that isn't on Lady Madonna (it's actually the Beatles singing into their cupped hands) and the soaring guitar sound of Pink Floyd's Dave Gilmour. Listen to our top 5 below, and read our explanations of the effects involved. 1 Barber's shop illusion (Listen with headphones) This is a demonstration of the stereo effect. Listening to it, you feel as though you are in a barber's chair, with the barber moving around you, clipping away at your hair. As the barber "moves" to your right, the volume increases slightly in the right channel and decreases in the left. Similarly, increases in the volume of sound from the clippers give the impression that he is bringing them closer and closer to each ear. The illusion demonstrates our ability to locate sounds in space; by comparing the inputs to the two ears, we can work out where a sound is coming from. 2 Phantom words (Listen through stereo separated loudspeakers, best placed some distance apart) © Copyright Reed Business Information Ltd

Keyword: Hearing
Link ID: 11328 - Posted: 06.24.2010

New research finds both men and women can lower the risk of stroke by engaging in even moderate exercise. Previous studies on fitness and strokes have focused more on men, but the new research says benefits apply to women, too. The research data covers 61,000 adults at an aerobics centre in Dallas, who were followed for an average of 18 years. The study found for those with moderate levels of fitness, the stroke risk went down by 15 to 30 per cent for men and 23 to 57 per cent for women. The lower risks were true even considering such other risk factors as smoking, weight and high blood pressure. Study leader Steven Hooker of the University of South Carolina's Prevention Research Centre says most people can become moderately fit by walking briskly for 30 minutes a day, five times a week. Stroke is the third-leading cause of death in the U.S. and doctors say physical activity can help prevent blockages in blood vessels that can cause it. In Canada, strokes kill 50,000 people a year, according to the Heart and Stroke Foundation of Canada. © The Canadian Press, 2008

Keyword: Stroke
Link ID: 11327 - Posted: 06.24.2010

LA CROSSE, Wis. - For as long as he can remember, Brad Williams has been able to recall the most trifling dates and details about his life. For example, he can tell you it was Aug. 18, 1965, when his family stopped at Red Barn Hamburger during a road trip through Michigan. He was 8 years old at the time. And he had a burger, of course. “It was a Wednesday,” recalled Williams, now 51. “We stayed at a motel that night in Clare, Michigan. It seemed more like a cabin.” To Williams and his family, his ability to recall events — and especially dates — is a regular source of amusement. But according to one expert, Williams’ skill might rank his memory among the best in the world. Doctors are now studying him, and a woman with similar talents, hoping to achieve a deeper understanding of memory. Williams, a radio anchor in La Crosse, seems to enjoy having his memory tested. Name a date from the last 40 years and, after a few moments, he can typically tell you what he did that day and what was in the news. Exercise your mind “Let’s see,” he mused, gazing into the distance for about five seconds. “That would be around when Magic Johnson announced he had HIV. Yes, a Thursday. There was a big snowstorm here the week before.” © 2008 The Associated Press.

Keyword: Learning & Memory
Link ID: 11326 - Posted: 06.24.2010

You’ve seen the TV shows and movies, someone implanted with electronic devices that give them super human powers, including super vision. In reality, the best we can do is a set of binoculars, or strap-on night vision goggles. But that all could change as engineers work to supercharge contact lenses. “If you look at the structure of a contact lens,” says Babak Parviz, University of Washington assistant professor of eleectrical engineering, “ more or less it’s just a polymer that … does vision correction.” Since the group was already working on incorporating micron-scale devices onto unconventional substrates including plastics, he says, “we saw the opportunity to integrate these on a contact lens.” Parviz adds that much of the micro technology that would have to fit on a contact lens is already available and says, “To look at the semi-conductor industry and what we have in opto-electronics and micro machines, we already have a lot… (but) one thing we have not done is to put those things on a contact.” Parviz imagines a whole list of things a supercharged contact lens might do, explaining, “I can see this exponentially growing and having many, many applications; from lenses that are quote-unquote intelligent and can help the user who’s had a cataract surgery to see better, to amplified vision, to all sorts of gaming applications and interfacing with your iPod and lots of things.” © ScienCentral, 2000-2008.

Keyword: Vision; Robotics
Link ID: 11325 - Posted: 06.24.2010

A computer does better than a doctor at diagnosing certain brain diseases, research has suggested. Experts taught a standard computer how to diagnose Alzheimer's from brain scans, and got a 96% success rate. The accuracy of diagnosis from standard scans, blood tests and interviews carried out by a clinician is 85%. The findings, published in the journal Brain, could lead to earlier diagnosis and more successful treatment of dementias, say scientists. Researchers from the Wellcome Trust Centre for Neuroimaging at University College London say computers have several advantages for diagnosing Alzheimer's - a condition caused by the build-up of plaques and tangles of tissue in the brain. Professor Richard Frackowiak said the computers were better able to distinguish signs of Alzheimer's than humans, and proved cheaper, faster and more accurate than current methods. "It's beginning to look like it will have to come into clinical practice," he said. "Machines are clearly able to do that sort of thing better." The method involves teaching a standard computer the difference between brain scans from patients with proven Alzheimer's disease and people with no signs of the disease at all. The two conditions can be distinguished with a high degree of accuracy on a single clinical MRI scan without the need for time consuming follow-up tests, say the scientists. (C)BBC

Keyword: Brain imaging; Alzheimers
Link ID: 11324 - Posted: 02.22.2008

Strokes have tripled in recent years among middle-aged women in the U.S., an alarming trend doctors blame on the obesity epidemic. Nearly two per cent of women ages 35 to 54 reported suffering a stroke in the most recent federal health survey, from 1999 to 2004. Only about half a per cent reported strokes in the previous survey, from 1988 to 1994. The percentage is small because most strokes occur in older people. But the sudden spike in middle-age and the reasons behind it are ominous, doctors said in research presented Wednesday at a medical conference. In a "pre-stroke population" of middle-age women, a tripling of cases is "an alarming increase," said Dr. Ralph Sacco, neurology chief at the University of Miami Miller School of Medicine. The spike in middle-aged strokes happened even though more women in the recent survey were on medicines to control their cholesterol and blood pressure — steps that lower the risk of stroke. The new research means "we need to redefine our textbooks about stroke in women," because they may now be more at risk in middle-age than men, said Dr. Philip Gorelick, neurology chief at the University of Illinois in Chicago and chairman of the stroke conference. © The Canadian Press, 2008

Keyword: Stroke
Link ID: 11323 - Posted: 06.24.2010

A better understanding of how memory works is emerging from a newfound ability to link a learning experience in a mouse to consequent changes in the inner workings of its neurons. Researchers, supported in part by the National Institutes of Health's National Institute of Mental Health (NIMH), have developed a way to pinpoint the specific cellular components that sustain a specific memory in genetically-engineered mice. "Remarkably, this research demonstrates a way to untangle precisely which cells and connections are activated by a particular memory," said NIMH Director Thomas Insel, M.D. "We are actually learning the molecular basis of learning and memory." For a memory to last long-term, the neural connections holding it need to be strengthened by incorporating new proteins triggered by the learning. Yet, it's been a mystery how these new proteins — born deep inside a neuron — end up becoming part of the specific connections in far-off neuronal extensions that encode that memory. By tracing the destinations of such migrating proteins, the researchers located the neural connections, called synapses, holding a specific fear memory. In the process, they discovered these synapses are distinguished by telltale molecular tags that enable them to capture the memory-sustaining proteins. Mark Mayford, Ph.D., and Naoki Matsuo, Ph.D., of the Scripps Research Institute, report on their findings in the February 22, 2008 issue of the journal Science.

Keyword: Learning & Memory
Link ID: 11322 - Posted: 06.24.2010

Matt Kaplan An accidental encounter with a pod of sleeping sperm whales has opened researchers’ eyes to some unknown sleep behaviours of these giant sea creatures. Counter to previous assumptions, and unlike smaller cetaceans, the whales seem to enter a period of full sleep. But they also sleep for a very limited time per day, hinting that they could be the least sleep-dependent mammals known. A team led by Luke Rendell at the University of St Andrew’s, UK, were monitoring calls and behaviour in sperm whales (Physeter macrocephalus ) off the northern Chile coast when they accidentally drifted into the middle of a pod of whales hanging vertically in the water, their noses poking out of the surface. At least two of the whales were facing the boat, but not a single animal responded. “It was actually pretty scary. The boat had drifted into the group with its engine off [while] I was below decks making acoustic recordings,” says Rendell. “Once I saw the situation I decided the best thing to do was to try and sail our way out of the group rather than turn the engine on and have them all react.” The researchers was almost successful, but unfortunately they nudged one of the whales on the way out. “We had no idea how they would react; each of the animals probably weighed up to twice as much as our boat, and could have sunk us. If they had decided to take action collectively — sperm whales do engage in communal defence [against] killer whales — then we could have been in real trouble,” Rendell says. Fortunately for everyone on board, after an initial jolt of activity the whales timidly moved away, and within fifteen minutes were bobbing peacefully at the surface again. © 2008 Nature Publishing Group

Keyword: Sleep; Evolution
Link ID: 11321 - Posted: 06.24.2010

Even the shortest of catnaps may be enough to improve performance in memory tests, say German scientists. Just six minutes "shut-eye" for volunteers was followed by significantly better recall of words, New Scientist magazine reported. "Ultra-short" sleep could launch memory processing in the brain, they suggested. One UK researcher disagreed, saying that longer sleep was needed to have an impact on memory. Dozens of studies have probed the relationship between sleep and memory, with clear evidence that body's natural sleep-wake cycle plays an important role. The team from the University of Dusseldorf wanted to see just how short a sleep could have any discernable impact. They used a group of students who were asked to remember a set of words, then given an hour's break before testing. During that hour, some of the students were allowed to sleep for approximately six minutes, while the rest were kept awake. Remarkably, on waking, the napping students performed better in the memory test. Some theories suggests that the processing of memories takes place in deep sleep, a phase which does not normally start until at least 20 minutes after falling asleep. However, the team, led by Dr Olaf Lahl, said that it was possible that the moment of falling asleep triggered a process in the brain that continued regardless of how long the person actually stayed awake. "To our knowledge, this demonstrates for the first time that an ultra-brief sleep episode provides an effective memory enhancement," he wrote. (C)BBC

Keyword: Sleep; Learning & Memory
Link ID: 11320 - Posted: 02.21.2008

By ANDREW POLLACK Scientists reported on Wednesday that they were able to control diabetes in mice by harnessing human embryonic stem cells. The work raised the prospect that the embryonic cells might one day be used to provide insulin-producing replacement cells to treat the disease in people. The scientists, at the biotechnology company Novocell, turned the stem cells into cells that produced insulin in the mice. Those cells kept blood sugar in check after the mice’s own insulin-producing cells were destroyed. “For those who say there is not much evidence that embryonic stem cells can cure diabetes, there you go,” said Dr. Camillo Ricordi, director of the Diabetes Research Institute at the University of Miami, who was not involved in the research. Still, a small number of the mice developed tumors, and some experts said the cells might not be well-characterized enough for use in people. In any event, Novocell said it would be several years before any human tests could begin. Doctors are already experimenting with transplants of insulin-producing islet cells from cadavers for patients with Type 1 diabetes, a disease that destroys a person’s own islet cells. In some cases, the transplant recipients have not needed daily injections of insulin, at least for a while. Copyright 2008 The New York Times Company

Keyword: Obesity; Stem Cells
Link ID: 11319 - Posted: 06.24.2010

By Darren Waters Gamers will soon be able to interact with the virtual world using their thoughts and emotions alone. A neuro-headset which interprets the interaction of neurons in the brain will go on sale later this year. "It picks up electrical activity from the brain and sends wireless signals to a computer," said Tan Le, president of US/Australian firm Emotiv. "It allows the user to manipulate a game or virtual environment naturally and intuitively," she added. The brain is made up of about 100 billion nerve cells, or neurons, which emit an electrical impulse when interacting. The headset implements a technology known as non-invasive electroencephalography (EEG) to read the neural activity. Ms Le said: "Emotiv is a neuro-engineering company and we've created a brain computer interface that reads electrical impulses in the brain and translates them into commands that a video game can accept and control the game dynamically." Headsets which read neural activity are not new, but Ms Le said the Epoc was the first consumer device that can be used for gaming. "This is the first headset that doesn't require a large net of electrodes, or a technician to calibrate or operate it and does require gel on the scalp," she said. "It also doesn't cost tens of thousands of dollars." The use of Electroencephalography in medical practice dates back almost 100 years but it is only since the 1970s that the procedure has been used to explore brain computer interfaces. (C)BBC

Keyword: Robotics; Emotions
Link ID: 11318 - Posted: 02.21.2008