Scientists are developing a cochlear implant which could allow deaf people to hear music. Existing implants allow people to listen easily to speech, but not music. But a team at the UK's National Physical Laboratory have developed a device with a wider frequency range, which improves musical appreciation. New Scientist magazine reports the whole implant could be put into the ear - current models require people to wear a box behind their ears. The cochlea in the ear contains fluid and hairs which vibrate in response to sounds. These hairs can stop vibrating, meaning people go deaf. It can happen at any age but can be particularly difficult for children as it affects their ability to do well at school and socialise. Cochlear implants currently involve putting an electrode inside the ear and an external box, which contains a microphone to pick up the sound, converts it from radiowaves into electrical signals and contains batteries to power the implant. Conventional hearing aids simply amplify sound rather than making it clearer. (C)BBC

Keyword: Hearing
Link ID: 8050 - Posted: 10.20.2005

Researchers at the University of Toronto (U of T), Capital Health's Stollery Children's Hospital in Edmonton, Toronto's Hospital for Sick Children and their international collaborators have discovered a genetic abnormality that causes a type of language impairment in children – a discovery that could lead to isolating genes important for the development of expressive language. A study published in the Oct. 20 issue of the New England Journal of Medicine outlines the discovery of a genetic abnormality in a nine-year-old boy with learning difficulties and speech problems from northern Alberta. By using some of the latest genetic screening methods designed to look for differences in the amount of DNA in particular chromosomes, the researchers discovered that the boy carries additional copies (termed duplication) of around 27 genes on chromosome 7. This is only the second instance of the identification of a single chromosome region linked to specific language impairment. The boy can understand what is said to him at the level of a seven-year-old but his expressive language and speech are at the level of a two-and-a-half-year-old. "Our results show that changes in the copy number of specific genes can dramatically influence human language abilities," says senior author Lucy Osborne, a U of T professor of medicine. "Based on our findings, we are expanding the study to assess the frequency of this DNA duplication in children with expressive language delay."

Keyword: Language; Genes & Behavior
Link ID: 8049 - Posted: 06.24.2010

We all know the site of a tragic accident. A four by four tossed over a highway barrier. A white sheet on the ground. Police with heads bent. As we pass, it seems like the most courteous action would be to avert our eyes, but still we glance over to the awful scene. Vanderbilt University psychologist David Zald says that's dangerous because, what he calls "emotional" images -- like car accidents, a gruesome murder scene, or a bit of pornography -- can briefly blind us to everything else around us, limiting our senses and potentially putting us at risk. "When [visual] information comes into the brain it has to get funneled through a relatively small area… only so much information can pass though at a time," explains Zald. "So what happens is, if there's a piece of emotional information, it basically gets jammed into the space… and nothing else is passing through." Zald and a group of colleagues based at Yale University report in the November issue of Psychonomic Bulletin and Review that they trained 21 people to spot a target image among a series of pictures flying by on a computer screen at a rate of 10 pictures per second. The target image is what the researchers call a "neutral" image, such as a picture of a building or a landscape. Study participants had to determine if the target image was rotated to the left or the right. © ScienCentral, 2000-2005.

Keyword: Vision; Emotions
Link ID: 8048 - Posted: 06.24.2010

Researchers are now understanding in greater detail the molecular machinery underlying the short-term brain changes that produce the high of cocaine, as well as the longer-term changes behind addiction. Their findings offer hope for targeted drugs that can short-circuit that addiction machinery. In the October 20, 2005, issue of Neuron, researchers led by Eric J. Nestler and Arvind Kumar of The University of Texas Southwestern Medical Center have pinpointed a key molecular mechanism by which genes are switched on in the brain that govern both short-term and long-term effects of cocaine. Such activation is called transcriptional activation because it induces the gene to begin making copies of itself into messenger RNA that trigger protein production. In their experiments, the researchers studied a process called "chromatin remodeling"--in which the histone proteins enfolding genes are chemically altered to render the genes active. They administered to rats both short-term, acute cocaine doses and long-term, chronic cocaine and analyzed the alteration of the histones affecting specific genes involved in cocaine response in the brain.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 8047 - Posted: 10.20.2005

Fetal alcohol syndrome (FAS), a disorder that is indicated by distinct facial characteristics, growth retardation, and poor intellectual and attentional function, can occur when mothers drink alcohol heavily during pregnancy. A new study in the October issue of The Journal of Pediatrics shows that prenatal alcohol exposure can also affect an infant's visual acuity or sharpness of vision. Sandra W. Jacobson, Ph.D. and colleagues from Wayne State University and University of Cape Town evaluated 131 infants of mixed ancestry in Cape Town, South Africa. After interviewing each mother to ascertain her alcohol consumption during pregnancy, the authors tested the visual acuity of the infants at 6 ˝ months of age using the Teller Acuity Cards (TAC) Test, which is comprised of gray cards with a concentration of vertical black and white stripes on the left or the right side. An examiner looked through a peephole in the center of the card to determine where the infant was looking. Poor visual acuity was indicated when the infant was not looking at the side containing the lines. Of the infants examined, 22 met the criteria for being diagnosed with FAS, and their visual acuity was significantly poorer than those without FAS. 27% of the infants with FAS scored below the fifth percentile, as opposed to the 9% of the infants without FAS. However, half of the infants with low TAC scores who did not meet the criteria for full FAS were born to mothers who reported binge drinking (greater than 5 drinks per occasion) during pregnancy.

Keyword: Drug Abuse; Vision
Link ID: 8046 - Posted: 10.20.2005

By GARDINER HARRIS The use of sleeping pills among children and very young adults rose 85 percent from 2000 to 2004, in yet another sign that parents and doctors are increasingly turning to prescription medications to solve childhood health and behavioral problems. And about 15 percent of people under age 20 who received sleeping pills were also being given drugs to treat attention deficit and hyperactivity disorder, according to the study by Medco Health Solutions, a managed-care company that makes estimates about medication use in the whole population based on extrapolations from its own data. Drugs used to treat attention disorders can cause insomnia. Few of the prescriptions given to children and young adults have the approval of the Food and Drug Administration because no sleep medication has been approved for use in children under 18. Still, doctors commonly use medications for patients and disorders for which the drugs have never received formal approval, particularly when those patients are children. Dr. Robert Epstein, Medco's chief medical officer, said, "It leads you to wonder whether these children are being treated for insomnia caused by hyperactivity or whether the medication itself causes the insomnia." The use of sleeping medicines among adults doubled from 2000 to 2004, Medco found. Copyright 2005 The New York Times Company

Keyword: Sleep
Link ID: 8045 - Posted: 10.19.2005

By BENEDICT CAREY They seem almost alive: snapshots of the living human brain. Not long ago, scientists predicted that these images, produced by sophisticated brain-scanning techniques, would help cut through the mystery of mental illness, revealing clear brain abnormalities and allowing doctors to better diagnose and treat a wide variety of disorders. And nearly every week, it seems, imaging researchers announce another finding, a potential key to understanding depression, attention deficit disorder, anxiety. Yet for a variety of reasons, the hopes and claims for brain imaging in psychiatry have far outpaced the science, experts say. Dr. Helen Mayberg of Emory found a baffling pattern of brain activity. After almost 30 years, researchers have not developed any standardized tool for diagnosing or treating psychiatric disorders based on imaging studies. Copyright 2005 The New York Times Company

Keyword: Depression; Brain imaging
Link ID: 8044 - Posted: 10.19.2005

By BENEDICT CAREY The Dalai Lama, the exiled leader of Tibet who is revered as a spiritual teacher, is at the center of a scientific controversy. He has been an enthusiastic collaborator in research on whether the intense meditation practiced by Buddhist monks can train the brain to generate compassion and positive thoughts. Next month in Washington, the Dalai Lama is scheduled to speak about the research at the annual meeting of the Society for Neuroscience. But 544 brain researchers have signed a petition urging the society to cancel the lecture, because, according to the petition, "it will highlight a subject with largely unsubstantiated claims and compromised scientific rigor and objectivity." Defenders of the Dalai Lama's appearance say that the motivation of many protesters is political, because many are Chinese or of Chinese descent. The Dalai Lama fled Tibet in 1959 after the Chinese crushed a Tibetan bid for independence. But many scientists who signed the petition say they did so because they believe that the field of neuroscience risks losing credibility if it ventures too recklessly into spiritual matters. Copyright 2005 The New York Times Company

Keyword: Miscellaneous
Link ID: 8043 - Posted: 10.19.2005

By DAVID WILLIAMSON CHAPEL HILL -- In a new study of cichlid fish descended from others caught in East Africa’s Lake Tanganika, scientists have made some surprising observations about how those animals respond to changes in their environments known as "social opportunities." Dr. Sabrina S. Burmeister, assistant professor of biology at the University of North Carolina at Chapel Hill’s College of Arts and Sciences, and colleagues found that subordinate male fish underwent a radical and rapid transformation when more dominant males were removed. "When we took dominant cichlid males from an experimental tank, subordinate males started becoming dominant themselves in as few as two minutes," Burmeister said. "Their colors -- blue and yellow -- got much brighter, a black stripe we call an eye bar appeared near their eyes, and they became much more aggressive than they were before. The remaining males also quickly paid a lot more attention to females because for the first time, they had an opportunity to reproduce." No one had any idea before that perceived changes in their social status could begin altering animals’ behavior and appearance so quickly, she said. Previous studies had shown the changes took as long as a week and were associated with increased fertility.

Keyword: Sexual Behavior; Aggression
Link ID: 8042 - Posted: 06.24.2010

Babies should get their Z's on their backs, most pediatricians advise parents. Beyond that, preventing Sudden Infant Death Syndrome, or SIDS — the number one cause of death in children under the age of one — has remained a mystery that researchers believe they may have finally cracked. Nino Ramirez, a neuroscientist at the University of Chicago, says that after nearly ten years spent unraveling the secrets of mouse nerve cells called pacemaker neurons he may have found the missing link that explains why some babies fall to SIDS. Ramirez and his team differentiated between two types of pacemaker cells active in the mouse brainstem that appear to control breathing — one group depends on calcium channels to operate and the other on sodium channels regulated by serotonin, a brain chemical known to influence mood. The latter held particular interest for Ramirez since prior research showed that babies who died of SIDS had serotonin deficits in brain areas that controlled breathing. "The idea with the serotonin is as follows," he explains. "It's present within the nervous system and these nerve cells are sitting in a soup of this serotonin. They need this…in order to generate this intrinsic ability to burst." That bursting triggers the respiratory system to gasp, which resets breathing. © ScienCentral, 2000-2005.

Keyword: Sleep
Link ID: 8041 - Posted: 06.24.2010

Atypical antipsychotic drugs seem to confer a small increased risk for death when used in people with dementia, concludes a team of researchers from the Keck School of Medicine of the University of Southern California in a meta-analysis of 15 clinical trials published in the October 19 issue of the Journal of the American Medical Association. Despite this risk, says Lon Schneider, M.D., professor of psychiatry, neurology, and gerontology at the Keck School and the USC Andrus School of Gerontology, physicians, families and patients need to keep in mind that psychosis itself is a very serious issue in dementia. "Aggression, hallucinations and delusions in dementia patients can also shorten a patient's life, and result in poor care and rapid deterioration," Schneider says. "It's a difficult problem with no easy answers." Led by Schneider, the USC researchers analyzed the results of the 15 trials--nine of which are unpublished--to determine whether there was a correlation between the use of these second-generation drugs (the atypical antipsychotics) and an increased risk for death.

Keyword: Alzheimers; Schizophrenia
Link ID: 8040 - Posted: 10.19.2005

Roxanne Khamsi Patients who suffer a stroke could get their movement and feeling back with the helping hand of magnetic pulses fired at their brains, according to new research. The experimental technique, called repetitive transcranial magnetic stimulation (rTMS), involves placing an electromagnetic coil above the scalp and releasing magnetic pulses that pass through the skull. The alternating magnetic fields cause ionic compounds inside nerve cells to flow, affecting brain activity. Over the past decade, this procedure has been used in everything from helping with brain imaging studies to treating depression, sometimes by apparently suppressing brain activity. But its full effects still aren't understood. Hubert Dinse of the Ruhr University in Bochum, Germany and his colleagues were investigating the effects of rTMS on motor activity. Experts had previously shown that magnetic pulses aimed at particular parts of the brain can cause certain muscle groups, such as those in the hand, to twitch. So Dinse and colleagues used very strong, single magnetic pulses to try and locate the motor region of the brain associated with the right index finger in 33 healthy participants. ©2005 Nature Publishing Group

Keyword: Stroke
Link ID: 8039 - Posted: 06.24.2010

No matter how trendy, all tobacco products including cigarettes, cigars, even the latest “in” smokes called bidis, come with a high price. Long-term smoking can lead to fatal heart attacks, strokes, emphysema, and cancer. Yet in the face of these negative consequences, a 2003 government survey estimated that nearly 71 million Americans had used some type of tobacco product in the past month. Many users are addicted. They have lost control over their use of tobacco and find it extremely dificult to stop smoking on their own. Nearly 35 million smokers make a serious attempt to quit each year, according to the National Institute on Drug Abuse. Unfortunately less than 7 percent who try to quit on their own remain tobacco-free more than a year. Most return to smoking within a few days. In the past, little could be done to help keep tobacco users from smoking except for counseling programs, which can be costly and do not always work. Thanks, however, to discoveries on the chemistry of tobacco's effects, some biology-based treatments are now available and even more help is on the way. The research is leading to an increased understanding of tobacco addiction and a wider range of treatment options for individuals hooked on cigarettes or other tobacco products. © 2005 Society for Neuroscience

Keyword: Drug Abuse
Link ID: 8038 - Posted: 06.24.2010

By Carl Zimmer In the past, most of the big news about human evolution came from remote dig sites in places like Africa or Indonesia. In the future, the big news will come from familiar sites closer to home: hospitals. That’s because hospitals are equipped with powerful new scanning machines primarily used to identify tumors, ballooning blood vessels, bone fractures, and a wide range of disorders in people. Those same scanners also make it possible for paleoanthropologists to look inside the fossils of ancient hominids and see things that until now have been shrouded in mystery. Take brains, for example. The evolution of the human brain is one of the most important questions in the story of our origins. But when our ancestors died, their brains quickly rotted away. Fossilized skulls offer the only clues. Until recently, if a team of researchers found an intact braincase, they were limited in what they could learn unless they cut the fossil open. Because hominid skulls are rare, few would dare take such a radical step. Now paleoanthropologists can put a hominid skull in a computed-tomography, or CT, scanner and create a virtual skull that they can split apart any way they want. If they remove that digital skull altogether, they leave behind the outlines of a virtual brain. In 2005 a virtual brain of the one known skull of Homo floresiensis—the three-foot-tall hominid discovered on the Indonesian island of Flores—provided evidence in the ongoing debate about whether the creature represents a separate species or was a human pygmy with a birth defect. The size and shape of the virtual brain lends credence to the separate species theory. Moreover, the brain was not just a simpler version of a human brain. Some regions were smaller than ours, but others were unusually large for such a small hominid, hinting that Homo floresiensis might have been capable of abstract thought and could make complicated plans. © 2005 The Walt Disney Company.

Keyword: Evolution
Link ID: 8037 - Posted: 06.24.2010

Australia has more things that will kill you than anywhere else. . . . This is a country where even the fluffiest of caterpillars can lay you out with a toxic nip, where seashells will not just sting you but actually sometimes go for you. . . . It’s a tough place. —Bill Bryson, In a Sunburned Country Raised, as you probably were, on film or video footage of drowsy koalas hugging eucalyptus trees, or kangaroos bouncing happily around the outback, you might wonder just what country Bryson is talking about. But consider the unassuming cone shell—just the kind of malicious mollusk that will “actually sometimes go for you.” The cone shell is a marine snail that lives in tropical regions worldwide, including the waters around northeastern Australia’s Great Barrier Reef. The snail aggressively reaches out to sting prey or would-be predators, injecting toxins that are among the most powerful in the animal kingdom. Even a diminutive member of the genus Conus can carry enough venom to kill a dozen people; a single careless encounter can bring death in less than thirty minutes. What’s more, the radula, a harpoonlike stinger that delivers the venom, can strike with enough speed and force to pierce a diver’s wetsuit. There is almost no pain associated with a cone-shell sting, because the venom contains a strong analgesic. That’s the good news. The bad news is that the toxin is a nerve agent for which there is no known antidote. © Natural History Magazine, Inc., 2005

Keyword: Neurotoxins
Link ID: 8036 - Posted: 06.24.2010

Christen Brownlee In the stoner stereotype, pot smokers and dying brain cells go hand in hand. However, new research suggests the situation may be more uplifting than that. A drug that functions as concentrated marijuana does may spur neurogenesis, the process by which the brain gives birth to new nerve cells. Previous research had suggested that neurogenesis happens only in select locations in the brain, such as the hippocampus, a region involved in learning and memory. Some studies have shown that this process is inhibited by most illicit drugs, such as cocaine, heroin, and methamphetamine. However, says Xia Zhang of the University of Saskatchewan in Saskatoon, marijuana's effect on neurogenesis has not been clear. He and his colleagues started investigating this mystery by searching cell surfaces in live, cultured slices of rat hippocampus for receptors that respond to marijuana and a few other similar drugs, called cannabinoids. They reasoned that if marijuana affected neurogenesis in the hippocampus, then cells in that area must have a way to recognize the drug. Sure enough, 95 percent of hippocampus cells responsible for neurogenesis showed evidence of cannabinoid 1 (CB1) receptors, one of two receptors that respond to cannabinoid drugs. ©2005 Science Service.

Keyword: Drug Abuse; Neurogenesis
Link ID: 8035 - Posted: 06.24.2010

By Marc Kaufman, Washington Post Staff Writer Pharmacies in black neighborhoods are much less likely to carry sufficient supplies of popular opioid painkillers than those in white neighborhoods, a new study has found, leading researchers to conclude that minorities are routinely undertreated for chronic pain. The study found that the disparity between what is available to patients in majority-black neighborhoods compared with majority-white areas had little to do with income levels, as pharmacies in wealthy black neighborhoods were no more likely to carry the prescription painkillers than those in poorer black neighborhoods. In wealthy white neighborhoods, however, pharmacies were far more likely to carry sufficient stock than in poor white communities. "The pharmacies in minority areas generally say they stock limited amounts of pain medication because the demand is not there," said Carmen R. Green, an associate professor at the University of Michigan Medical School, who led the research. "But the low-demand barrier does not ring true for me," she said. "We know that minorities are more at risk of suffering chronic pain, and maybe they don't come to local pharmacies because they've come to expect they won't carry the medicines they need." © 2005 The Washington Post Company

Keyword: Pain & Touch; Drug Abuse
Link ID: 8034 - Posted: 06.24.2010

By Christof Koch The brain is an amazingly dynamic organ. Millions of neurons in all corners of our gray matter send out an endless stream of signals. Many of the neurons appear to fire spontaneously, without any recognizable triggers. With the help of techniques such as electroencephalography (EEG) and microelectrode recordings, brain researchers are listening in on the polyphonic concert in our heads. Any mental activity is accompanied by a ceaseless crescendo and diminuendo of background processing. The underlying principle behind this seeming racket is not understood. Nevertheless, as everyone knows, the chaos creates our own unique, continuous stream of consciousness. And yet it is very difficult to focus our attention on a single object for any extended period. Our awareness jumps constantly from one input to another. No sooner have I written this sentence than my eyes move from the computer screen to the trees outside my window. I can hear a dog barking in the distance. Then I remember the deadline for this article--which isn't going to be extended again. Resolutely, I force myself to type the next line. How does this stream of impressions come to be? Is our perception really as continuous as it seems, or is it divided into discrete time parcels, similar to frames in a movie? These questions are among the most interesting being investigated by psychologists and neuroscientists. The answers will satisfy more than our curiosity--they will tell us if our experience of reality is accurate or a fiction and if my fiction is different from yours. © 1996-2005 Scientific American, Inc

Keyword: Vision
Link ID: 8033 - Posted: 06.24.2010

With around 64 percent of the population is either overweight or obese, health issues relating to being overweight have become almost epidemic in the U.S. Obesity causes "metabolic syndrome" — in which insulin-resistance leads to diabetes, heart disease and other aging diseases. Meanwhile, it's been observed that throughout the animal kingdom, animals from worms to mice to monkeys live longer, healthier lives when eating very low calorie diets. Anti-aging researchers say the evidence all shows that metabolic function is closely linked to the aging process. "Just reducing intake of calories has so many positive effects and we'd like to find the switches," says geneticist Stephen Spindler, professor of biochemistry at the University of California at Riverside. "There must be relatively few switches that that throws to cause us to change from a rapid aging, higher-disease state to a slower aging lower-disease state." As reported in Discover magazine, some biotech companies like Massachusetts-based Elixir Pharmaceuticals, want to design new drugs to mimic those effects. But Elixir researchers also predict that some already widely-used drugs may turn out to slow aging. "There are indeed medicines that are currently available that treat metabolic function that probably have a positive effect on lifespan," says Bill Heiden, Elixir President and CEO. © ScienCentral, 2000-2005

Keyword: Obesity
Link ID: 8032 - Posted: 06.24.2010

Andreas von Bubnoff The protein particles that cause illnesses such as mad cow disease can be found in the urine of infected mice, researchers report. Their study may solve the mystery of how such 'prion' diseases spread among animals such as sheep, elk and deer. But it also raises concerns that the urine of humans with new-variant Creutzfeldt-Jakob disease (vCJD) may contain dangerous proteins. Prions are primarily found in the brain, the spinal cord and the immune system. British cows are thought to have developed the prion disease bovine spongiform encephalopathy (BSE) by eating ground-up brains, spleens and similar material. Other body parts were thought to be relatively safe for consumption. Then, in 2003, Adriano Aguzzi's group at the University Hospital of Zurich, Switzerland, found prions in the muscle tissue of people who had died from a brain wasting disease. And this January, the team showed in mice that prions also spread to the pancreas, kidneys and liver if there is inflammation in these organs. Together, these findings suggested that the brain and lymphatic organs might not be the only dangerous ones. ©2005 Nature Publishing Group

Keyword: Prions
Link ID: 8031 - Posted: 06.24.2010