WASHINGTON - Toxins from cone snail venom may help point the way to better relief of severe nerve pain in people, researchers report. Results were promising in tests on rats with a type of nerve pain similar to sciatica, according to researchers led by J. Michael McIntosh, a biology professor at the University of Utah. McIntosh said he hopes this finding could lead to a new painkiller that could be taken orally, but it could take 10 years or more before the findings can be translated into a treatment for people. The findings were published Monday in the online edition of Proceedings of the National Academy of Sciences. The researchers found that the toxins from cone snails treated nerve pain by blocking molecules known as "a9a10 nicotinic acetylcholine receptors." The a9a10 NA receptors are located in several parts of the body including dorsal root ganglia — a group of nerve cells near the spine that is involved in pain transmission. Common pain relievers often fail with nerve pain, and stronger drugs such as morphine have side effects. © 2006 Yahoo! Inc. All rights reserved

Keyword: Pain & Touch
Link ID: 9616 - Posted: 06.24.2010

Jennifer Viegas, Discovery News — Music has the power to affect humans physically and emotionally, and now several new studies suggest it can have similar effects on other animals, from fish to monkeys. For example, non-human primates seem to prefer the relaxing strains of a lullaby over fast dance tunes, according to a forthcoming study in the journal Cognition that looked at the musical preferences of cotton-top tamarinds and marmosets. Josh McDermott, a researcher in the Perceptual Science Group at the Massachusetts Institute of Technology, and colleague Marc Hauser of Harvard University placed speakers near food-baited branches. Whenever the small monkeys plopped themselves on a branch, the researchers would play music out of the speakers. During various experiments, the scientists played a Russian folk lullaby performed on a flute, a rendition of the Mozart string concerto K458 in B flat major, a lullaby performed by a German singer or a fast techno track by Alec Empire called "Nobody Gets Out Alive." Repeatedly, the monkeys gravitated towards the branches next to speakers playing the slowest tempo tunes, which were usually the lullabies. © 2006 Discovery Communications Inc.

Keyword: Hearing
Link ID: 9615 - Posted: 06.24.2010

Jennifer Kay, Associated Press — Back in 1902, a scientist examining the smooth, grapefruit-size brain of a manatee remarked that the organ's unwrinkled surface resembled that of the brain of an idiot. Ever since then, manatees have generally been considered incapable of doing anything more complicated than chewing sea grass. But Hugh, a manatee in a tank at a Florida marine laboratory, doesn't seem like a dimwit. When a buzzer sounds, the speed bump-shaped mammal slowly flips his 1,300 pounds and aims a whiskered snout toward one of eight loudspeakers lowered into the water. Nosing the correct speaker earns him treats. Hugh is no manatee prodigy. Such sensory experiments, along with other recent studies, are revealing that sea cows aren't so stupid after all. Researchers contend that if the plant-eating beasts seem slow-witted, it is because they faced no threats to their survival before the advent of boat propellers. "They're not under any selection pressure to evolve the rapid-type behavior we've associated with hawks, a predator, or antelopes, a prey. They look like very contented animals that don't have very much to do all day," said Roger Reep, a neuroscientist at the University of Florida's College of Veterinary Medicine. The experiments under way at the independent Mote Marine Laboratory, could help scientists protect Florida's manatees, an endangered species, from propellers and other dangers. © 2006 Discovery Communications Inc.

Keyword: Evolution; Intelligence
Link ID: 9614 - Posted: 06.24.2010

Kerri Smith A new painkilling substance has been discovered that is up to six times more potent than morphine when tested in rats — and it's produced naturally by the human body. Natural painkillers are very rare, and researchers hope that this recent find might be harnessed as a clinical treatment. Naturally produced painkillers might help to avoid some of the side effects experienced by patients treated with synthetic compounds such as morphine, including addiction and tolerance with prolonged use. But the new substance will first have to be tested to confirm whether it will be an effective drug, experts warn. The compound, dubbed opiorphin, seems to work by prolonging the body's own defences against pain, explain Catherine Rougeot of the Pasteur Institute in Paris, France, and her colleagues, who report the discovery in Proceedings of the National Academy of Sciences1. It does so by preventing the breakdown of chemicals called enkephalins, which in turn activate opiate receptors that block pain signals from reaching the brain. Rougeot's team tracked down the new compound after previously finding a similar natural painkiller in rats, called sialorphin2. They wondered whether humans might produce something similar — and by analysing saliva samples, hit upon opiorphin. ©2006 Nature Publishing Group

Keyword: Pain & Touch
Link ID: 9613 - Posted: 06.24.2010

Andy Coghlan Saliva from humans has yielded a natural painkiller up to six times more powerful than morphine, researchers say. The substance, dubbed opiorphin, may spawn a new generation of natural painkillers that relieve pain as well as morphine but without the addictive and psychological side effects of the traditional drug. When the researchers injected a pain-inducing chemical into rats’ paws, 1 gram of opiorphin per kilogram of body weight achieved the same painkilling effect as 3 grams of morphine. The substance was so successful at blocking pain that, in a test involving a platform of upended pins, the rats needed six times as much morphine as opiorphin to render them oblivious to the pain of standing on the needle points. “Its pain-suppressive effect is like that of morphine,” says Catherine Rougeot at the Pasteur Institute in Paris, France, who led the research. “But we have to test its side effects as it is not a pure painkiller,” she says. “It may also be an anti-depressive molecule.” © Copyright Reed Business Information Ltd.

Keyword: Pain & Touch
Link ID: 9612 - Posted: 06.24.2010

By BENEDICT CAREY Paul Williams, 13, has had almost as many psychiatric diagnoses as birthdays. The first psychiatrist he saw, at age 7, decided after a 20-minute visit that the boy was suffering from depression. A grave looking child, quiet and instinctively suspicious of others, he looked depressed, said his mother, Kasan Williams. Yet it soon became clear that the boy was too restless, too explosive, to be suffering from chronic depression. Paul was a gifted reader, curious, independent. But in fourth grade, after a screaming match with a school counselor, he walked out of the building and disappeared, riding the F train for most of the night through Brooklyn, alone, while his family searched frantically. It was the second time in two years that he had disappeared for the night, and his mother was determined to find some answers, some guidance. What followed was a string of office visits with psychologists, social workers and psychiatrists. Each had an idea about what was wrong, and a specific diagnosis: “Compulsive tendencies,” one said. “Oppositional defiant disorder,” another concluded. Others said “pervasive developmental disorder,” or some combination. Each diagnosis was accompanied by a different regimen of drug treatments. Copyright 2006 The New York Times Company

Keyword: Depression; Schizophrenia
Link ID: 9611 - Posted: 06.24.2010

By Siri Schubert We do it automatically. As soon as we observe another person, we try to read his or her face for signs of happiness, sorrow, anxiety, anger. Sometimes we are right, sometimes we are wrong, and errors can create some sticky personal situations. Yet Paul Ekman is almost always right. The psychology professor emeritus at the University of California, San Francisco, has spent 40 years studying human facial expressions. He has catalogued more than 10,000 possible combinations of facial muscle movements that reveal what a person is feeling inside. And he has taught himself how to catch the fleeting involuntary changes, called microexpressions, that flit across even the best liar's face, exposing the truth behind what he or she is trying to hide. Ekman, 72, lives in Oakland, Calif., in a bright and airy house near the bay. As I talked with him there, he studied me, his eyes peering out from under bushy brows as if they were registering each brief facial tic I unknowingly exhibited. Does his talent make him a mind reader? "No," he says candidly. "The most I can do is tell how you are feeling at the moment but not what you are thinking." He is not being modest or coy; he is simply addressing the psychological bottom line behind facial expressions: "Anxiety always looks like anxiety," he explains, "regardless of whether a person fears that I'm seeing through their lie or that I don't believe them when they're telling the truth." The professor calls the ever present risk we all take of misreading a person's visage "Othello's error." © 1996-2006 Scientific American, Inc.

Keyword: Emotions
Link ID: 9610 - Posted: 06.24.2010

Researchers at the University of Rochester may have answered one of neuroscience's most vexing questions—how can it be that our neurons, which are responsible for our crystal-clear thoughts, seem to fire in utterly random ways? In the November issue of Nature Neuroscience, the Rochester study shows that the brain's cortex uses seemingly chaotic, or "noisy," signals to represent the ambiguities of the real world—and that this noise dramatically enhances the brain's processing, enabling us to make decisions in an uncertain world. "You'd think this is crazy because engineers are always fighting to reduce the noise in their circuits, and yet here's the best computing machine in the universe—and it looks utterly random," says Alex Pouget, associate professor of brain and cognitive sciences at the University of Rochester. Pouget's work for the first time connects two of the brain's biggest mysteries; why it's so noisy, and how it can perform such complex calculations. As counter-intuitive as it sounds, the noise seems integral to making those calculations possible. In the last decade, Pouget and his colleagues in the University of Rochester's Department of Brain and Cognitive Sciences have blazed a new path to understanding our gray matter. The traditional approach has assumed the brain uses the same method computation in general had used up until the mid-80s: You see an image and you relate that image to one stored in your head. But the reality of the cranial world seems to be a confusing array of possibilities and probabilities, all of which are somehow, mysteriously, properly calculated.

Keyword: Miscellaneous
Link ID: 9609 - Posted: 06.24.2010

Christen Brownlee The burn of hot peppers and the searing pain of a spider bite may have a common cause. New research suggests that molecules in hot peppers and in a certain spider's venom target the same receptor on nerve cells. Several years ago, scientists identified a channel on neurons that's opened by capsaicin, the molecule responsible for peppers' burn. Follow-up research showed that this channel is a member of a family of cell-surface receptors that sense both chemicals and temperature. When these channels are activated, ions flood into nerve cells and cause them to fire. Although scientists have already studied components of spider venom that cause shock, paralysis, and death, little is known about the molecules that cause the pain. David Julius of the University of California, San Francisco and his colleagues wondered whether pain-inducing venom ingredients might activate the dual-purpose cell-surface channels. The team purchased venoms collected from a variety of spider, scorpion, and snail species known to deliver painful bites. The researchers diluted the venoms and added them to dishes containing human-kidney cells that had been genetically altered to carry various types of channels. ©2006 Science Service.

Keyword: Pain & Touch; Neurotoxins
Link ID: 9608 - Posted: 06.24.2010

BUFFALO, N.Y. -- A 40-year-old woman in good health falls and hits her head while visiting her roommate at her workplace. After a trip to the emergency department, her roommate takes her home with limited instructions. Two days later she finds her dead in her bedroom from a brain hemorrhage. This tragic, but true, vignette illustrates the problem of patients leaving emergency departments after suffering a concussion or mild traumatic brain injury without clear and thorough information about the signs of impending complications. In a study published in a recent issue of Brain Injury, researchers at the University at Buffalo found that discharge sheets from 14 of 15 hospitals that were reviewed lacked at least one important sign of a possible hemorrhage. Ten of the hospitals were located in Western New York; five were located in southern Ontario, Canada. In addition, most instruction sheets were written at too high a reading level. Some suggestions for concussion management were simply wrong, said Michael Fung, M.D., a Canadian physician doing a fellowship in UB's Sports Medicine Institute and the study's lead author. The signs accepted by brain specialists as associated most consistently with hemorrhage or equally dangerous swelling in the brain following a blow to the head are: vomiting, a worsening headache, amnesia or short-term memory loss, worsening mental status, loss of motor function or vision or speech and seizure, the study notes. © 2006 University at Buffalo.

Keyword: Brain Injury/Concussion
Link ID: 9607 - Posted: 06.24.2010

By Rick Weiss Blind mice regained some ability to see after getting transplants of cells taken from the eyes of other mice, strengthening the prospect that it may someday be possible to restore vision in some people who have lost most or all of their eyesight, scientists reported yesterday. Researchers in London and Michigan who did the work warned that it would be years before similar efforts might be tried in people who have lost their vision from macular degeneration or other kinds of blindness that might respond to the treatment. But they said the new study showed for the first time that light-detecting retina cells -- which in this case were taken from other animals but which scientists have begun to grow from human embryonic stem cells -- can orient themselves properly after being injected into a blind eye, connect to other nerve cells and communicate appropriately with visual centers in the brain. "It's still at the research stage, but it's very promising," said Anand Swaroop, a professor of ophthalmology, visual science and human genetics at the University of Michigan Medical School's W.K. Kellogg Eye Center in Ann Arbor. Swaroop led seminal work in recent years that identified the cells in the eye's retina that grow into "rod" cells during fetal development -- the cells that are responsible for black-and-white vision. © 2006 The Washington Post Company

Keyword: Vision; Regeneration
Link ID: 9606 - Posted: 06.24.2010

Poor Bridget Jones. At the beginning of the first film about her diary and life, the character, played by actress Renée Zellweger, is fat and alone in her apartment where she mimes one of the great self-pitying song hits of all time: "All by Myself." But Bridget's problem may be more than skin deep. In new research, reported in the current online issue of the journal Social Neuroscience, researchers from the University of Georgia and San Diego State University report for the first time that social exclusion actually causes changes in a person's brain function and can lead to poor decision-making and a diminished learning ability. "Our findings indicate that social rejection can be a powerful influence on how people act," said W. Keith Campbell, a psychologist who led the research. The new research is the first to examine subjects' brain patterns following social exclusion using the magnetoencephalography (MEG) technique. Researchers have known for a long time that there is a link between social exclusion and the failure of self-control. For instance, people who are rejected in social situations often respond by abusing alcohol, expressing aggression or performing poorly at school or work. (Bridget Jones chooses "vodka and Chaka Khan.") The new study, however, is the first to use MEG to show that there are actual changes inside the brain when test subjects are manipulated to feel socially excluded.

Keyword: Stress
Link ID: 9605 - Posted: 11.11.2006

Researchers at UC Irvine have found that how much detail one remembers of an event depends on whether a certain portion of the brain is activated to “package” the memory. The research may help to explain why sometimes people only recall parts of an experience such as a car accident, and yet vividly recall all of the details of a similar experience. In experiments using functional magnetic resonance imaging (fMRI), the scientists were able to view what happened in the brains of subjects when they experienced an event made up of multiple contextual details. They found that participants who later remembered all aspects of the experience, including the details, used a particular part of the brain that bound the different details together as a package at the time the event occurred. When this brain region wasn’t activated to bind together the details, only some aspects of an event were recalled. The findings appear in the current issue of Neuron. “This study provides a neurological basis for what psychologists have been telling us for years,” said Michael Rugg, director of UCI’s Center for the Neurobiology of Learning and Memory and senior author of the paper. “You can’t get out of memory what you didn’t put into it. It is not possible to remember things later if you didn’t pay attention to them in the first place.” © Copyright 2002-2006 UC Regents

Keyword: Learning & Memory
Link ID: 9604 - Posted: 06.24.2010

By TINA KELLEY NEWARK, — A New Jersey couple filed suit against Aetna Inc., the Hartford-based insurance company, on Wednesday, claiming that it refused to fully cover their daughter’s treatment for anorexia. More Multimedia: Slide Show: At the Polls Slide Show: Spitzer on the Trail The suit was filed in United States District Court here. The couple, Cliff and Maria DeAnna of Mountainside, N.J., said Aetna refused to pay for nearly 10 weeks of their daughter’s inpatient treatment, saying her eating disorder was not “biologically based.” Insurers have balked at covering mental illnesses that they say do not have a proven physiological basis. Ms. DeAnna, who declined to provide her daughter’s given name for privacy reasons, said by phone that she had been hospitalized for 101 days so far this year but that Aetna U.S. Healthcare H.M.O. would pay for only 35 inpatient days. Symptoms of anorexia include excessive dieting and exercise and a distorted belief that one is overweight. The case is an example of what advocates for the mentally ill call longstanding inequities in insurance coverage for psychological ailments. The family’s lawyer, Bruce Nagel, said state law required insurers to provide the same coverage for mental and nervous conditions as for physiological diseases, like heart ailments or emphysema. The suit estimates that hundreds of people in New Jersey have had similar difficulties receiving coverage, and it seeks certification as a class action. Ms. DeAnna estimates that her family has paid almost $100,000 in medical bills this year alone, with the help of a home equity loan. Her daughter, who is 20 and stands 5-foot-6, weighed 102 pounds when she last went into the hospital. Copyright 2006 The New York Times Company

Keyword: Anorexia & Bulimia
Link ID: 9603 - Posted: 06.24.2010

Washington, DC -- Neuroscientists had long believed that the only way to repair a spinal cord injury was to grow new neural connections, but researchers at Georgetown University Medical Center have found that, especially in young rats, powerful cells near the injury site also work overtime to restrict nerve damage and restore movement and sensation. The same process does not work as efficiently in adult rats and thus recovery time is much longer, the researchers also discovered. But they say that now that they know such a mechanism exists, it may be possible one day to “switch” these cells on therapeutically ? and possibly help humans function better following serious spinal cord injuries. “No one knew cells in the spinal cord acted to protect nerves in this way, so it gives us some hope that in the future we could stimulate this process in the clinic to enhance recovery and ensure the best outcome possible for patients,” said the senior author, Jean R. Wrathall, Ph.D., professor in the Department of Neuroscience. “This is an animal study, however, and there is much work to do to understand more about this process and how it might be altered,” Wrathall said. The study, whose first author is graduate student Philberta Y. Leung, is published in the November 2006 issue of the journal Experimental Neurology.

Keyword: Regeneration
Link ID: 9602 - Posted: 06.24.2010

Our eyes are constantly making saccades, or little jumps. Yet the world appears to us as a smooth whole. Somehow, the brain's visual system "knows" where the eyes are about to move and is able to adjust for that movement. In a paper published online this week in Nature, researchers at the University of Pittsburgh and the National Eye Institute (NEI) for the first time provide a circuit-level explanation as to why. "This is a classic problem in neuroscience," says Marc Sommer, assistant professor of neuroscience at Pitt, who coauthored the paper with Robert Wurtz, senior investigator at NEI, one of the National Institutes of Health. "People have been searching for a circuit to accomplish this stability for the last 50 years, and we think we've made good progress with this study." In 1950, Nobel laureate Roger Sperry hypothesized that when the brain commands the eyes to move, it also sends a corollary discharge, or internal copy, of that command to the visual system. Sommer and Wurtz showed in a 2002 Science paper that a pathway from brainstem to frontal cortex conveys a corollary discharge signal in the brains of monkeys. They suggested that this pathway might cause visual neurons of the cortex to suddenly shift their receptive field--their window on the world--just before a saccade. Such neurons with shifting receptive fields had been discovered by Pitt Professor of Neuroscience Carol Colby and colleagues in 1992.

Keyword: Vision
Link ID: 9601 - Posted: 11.09.2006

Helen Pearson Using a technique that may one day help blind people to see, researchers have shown in mice that retinal cells from newborns transplanted into the eyes of blind adults wire up correctly and help them to detect light. The finding challenges conventional biological thinking, because it shows that cells that have stopped dividing are better for transplantation than the stem cells that normally make new cells. For decades, researchers have sought a way to replace the light-detecting cells that carpet the back of our eyes — and which break down in diseases such as retinitis pigmentosa and macular degeneration. But they have struggled to find cells that will work normally after being transplanted into the eye. To find the best cell type, researchers led by Anand Swaroop at University of Michigan, Ann Arbor, and Robin Ali at University College London, UK, extracted cells from the retinas of mice at various times when photoreceptors are normally being generated, as embryos and after they are born. They then injected these cells into adult mouse retinas and counted how many new photoreceptors were generated. Cells produced in the few days after birth generated the most new photoreceptors after transplantation and connected to the retina correctly, they found. These cells were destined to be photoreceptors but had not fully matured into rods, the cells that detect low light. The results are published in Nature1. ©2006 Nature Publishing Group

Keyword: Vision; Regeneration
Link ID: 9600 - Posted: 06.24.2010

Roxanne Khamsi They may be cold-blooded, but some lizards have warm personalities and like to socialise, a new study shows. A behavioural study reveals that lizards have different social skills: some are naturally inclined to join large groups while others eschew company altogether. The discovery of reptilian personality types could help ecologists better understand and model animal population dynamics, say the researchers involved. Scientists define "personality differences" as consistent behavioural differences between individuals across time and contexts. But there is a need for more research on these differences in wild animals, says Julien Cote of the Pierre and Marie Curie University in Paris, France. "Psychologists have explored the considerable range of non-human personalities like sociability, but mostly on domesticated animals," he says. Cote and colleagues captured wild pregnant common lizards (Lacerta vivipara), and as soon as the offspring were born they were exposed to the scent of other lizards, to test their reactions. Over the next year the team monitored the newly born creatures to see how much time each spent in different areas of their enclosure. © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain
Link ID: 9599 - Posted: 06.24.2010

PITTSBURGH -- Timing is everything. For a mouse trying to discriminate between the scent of a tasty treat and the scent of the neighborhood cat, timing could mean life or death. In a striking discovery, Carnegie Mellon University scientists have linked the timing of inhibitory neuron activity to the generation of odor-specific patterns in the brain's olfactory bulb, the area of the brain responsible for distinguishing odors. Their work, appearing in the Nov. 8 issue of the Journal of Neuroscience, describes for the first time a cellular mechanism linking a specific stimulus to the timing at which inhibitory neurons fire. This breakthrough lays a cellular foundation for the "temporal coding hypothesis," which proposes that odor identity is encoded by the timing of neuronal firing and not the rate at which neurons fire. Past research has shown that specific odors trigger unique patterns of electrical activity in the brain. Generating these patterns requires reliably timed inhibition, but relatively little was known about the timing of the activity of inhibitory neurons -- until now. "There is a clear link between which odor is being presented and the time at which inhibitory neurons fire. This timing controls which excitatory neurons are active and at which time. This modulation contributes to the generation of reliable temporal patterns of neuronal activity," said Nathan Urban, an assistant professor of biological sciences at the Mellon College of Science at Carnegie Mellon.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 9598 - Posted: 11.08.2006

by Mary Tucker The sense of smell often seems like the forgotten sense, perhaps because scent cannot be transmitted as obviously as images or sound. But watch a dog - with a sense of smell about a million times more sensitive than ours - identify a person by their smell or sniff out traces of drugs and it is obvious what a powerful means of communication it can be. For humans, scent plays a big role in attraction and is strongly tied to memory. But how is smell written into molecules? And how do our noses interact with scent molecules? Since classical times, scientists have been trying to pin down solid olfactory rules but they still don't know exactly how the nose works. Decoding the shape of smell What we do know is the world is made of atoms and those atoms connect to make molecules. Molecules are what we smell, from wherever they are evaporating, and they reach our nose through the air. Though we know almost everything possible about molecules, we don't know how our nose reads them. Chemists make hundreds of new molecules every week but what each molecule is going to smell like is always a mystery. The prevailing theory, first refined in 1952 by John Amoore at Oxford University, is the shape or steric theory of odor. The theory, simply stated, proposes that the shape of a molecule determines its smell. In other words, a rose molecule smells like a rose molecule because its shape is coded precisely for the nose to interpret this way.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 9597 - Posted: 11.08.2006