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

A synthetic chemical similar to the active ingredient in marijuana makes new cells grow in rat brains. What is more, in rats this cell growth appears to be linked with reducing anxiety and depression. The results suggest that marijuana, or its derivatives, could actually be good for the brain. In mammals, new nerve cells are constantly being produced in a part of the brain called the hippocampus, which is associated with learning, memory, anxiety and depression. Other recreational drugs, such as alcohol, nicotine and cocaine, have been shown to suppress this new growth. Xia Zhang of the University of Saskatchewan in Saskatoon, Canada, and colleagues decided to see what effects a synthetic cannabinoid called HU210 had on rats' brains. They found that giving rats high doses of HU210 twice a day for 10 days increased the rate of nerve cell formation, or neurogenesis, in the hippocampus by about 40%. A previous study showed that the antidepressant fluoxetine (Prozac) also increases new cell growth, and the results indicated that it was this cell growth that caused Prozac’s anti-anxiety effect. Zhang wondered whether this was also the case for the cannabinoid, and so he tested the rats for behavioural changes. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse; Neurogenesis
Link ID: 8030 - Posted: 06.24.2010

Researchers have identified the first gene mutation associated with Tourette syndrome - opening a new avenue for understanding the complex disorder that causes muscle and vocal tics. Until now, causes of Tourette syndrome (TS), which afflicts as many as 1 in 100 people, have eluded researchers because the disease appears to be caused by subtle mutations in many genes. The researchers published their findings in the October 14, 2005, issue of the journal Science. Matthew W. State of the Yale University School of Medicine was senior author of the paper. His research was supported by a Howard Hughes Medical Institute institutional award to Yale that was used to support early research by promising scientists at Yale. According to State, early theories suggesting that a single gene mutation causes TS have proven incorrect. “There has been an evolving hypothesis about Tourette syndrome being a much more complex disorder,” State said. “I think there is general consensus at this point that there are likely to be multiple genes, likely interacting, and probably different sets of genes in different people, that contribute to TS.” The notion of multiple genes is borne out by the complex phenotype of the syndrome, which is often associated with obsessive-compulsive disorder, attention deficit hyperactivity disorder, or depression, said State. © 2005 Howard Hughes Medical Institute.

Keyword: Tourettes
Link ID: 8029 - Posted: 06.24.2010

BY FRED BORTZ Even staunch supporters of Darwinian evolution understand why many people find that theory hard to accept. We see ourselves as endowed with an intellect and culture (and, some would say, a soul) that set us apart from all other creatures. We are rational beings, while apes behave like -- well -- animals. And if scientific evidence persuades us that we are indeed evolved from apes, then surely we are more highly evolved than orangutans, gorillas, chimpanzees, and bonobos. Frans de Waal, an Emory University primatologist, would not agree. Those species are as highly evolved as our own. Their evolution simply followed different tracks. If we really want to understand what makes us human, de Waal argues in Our Inner Ape, we should not focus on our differences from apes, but rather examine the "fascinating and frightening parallels between primate behavior and our own, with equal regard for the good, the bad, and the ugly." That is precisely what he does in this book, with a wealth of stories and an entertaining style that does not sacrifice scientific depth or objectivity. He focuses on chimpanzees and bonobos because they are closest to humans, sharing a common ancestor as recently as 5.5 million years ago. After humans branched off, ancestral chimps and bonobos remained a single species for 3 million more years. Genetic evidence indicates that humans are more closely related to bonobos than to chimps, but only slightly so. Copyright 2005, Digital Chicago Inc

Keyword: Evolution; Sexual Behavior
Link ID: 8028 - Posted: 10.13.2005

We all need shut-eye, but some of us sleep much more soundly than others. Now, researchers have found a gene that appears to determine how intensely we sleep. When it comes to getting a good night's rest, not all sleep is the same. The most important stage of the sleep cycle is deep sleep--also known as slow wave sleep--the slumber where the brain's electrical activity is at its slowest. Even after only a few nights deprived of these roughly hour-long plunges into nothingness, body temperature and immune functions become unstable. In spite of its importance, not everyone gets the same amount of deep sleep, and studies of twins indicate that some of this variation is genetic. In mice, differences in sleep quality have been linked to a collection of genes regulating the neurotransmitter adenosine. (Adenosine is part of the pathway that caffeine inhibits to keep us awake.) Researchers studying rats found that the amount of deep sleep could be increased by chemically interfering with one of these adenosine-regulating genes, called adenosine deaminase (ADA). To see whether ADA plays a role in human sleep quality, a team led by Hans-Peter Landolt, a sleep physiologist at the University of Zurich, Switzerland, sequenced the gene in 119 student volunteers and hosted them for three nights of sleep in the lab. A tiny difference in DNA translates to a big improvement in sleep quality. Ten percent of the volunteers, who had a mutation in ADA, enjoyed about half an hour more deep sleep, as measured by electrical activity in the brain, than volunteers without the mutation, the team reports online this week in Proceedings of the National Academies of Science. Copyright © 2005 by the American Association for the Advancement of Science.

Keyword: Sleep
Link ID: 8027 - Posted: 06.24.2010

EAST LANSING, Mich. – A Michigan State University researcher and his colleagues have shown that playing violent video games leads to brain activity pattern that may be characteristic for aggressive thoughts. In a functional magnetic resonance imaging (fMRI) study, 13 male research participants were observed playing a latest-generation violent video game. Each participant’s game play was recorded and content analyzed on a frame-by-frame basis. “There is a causal link between playing the first-person shooting game in our experiment and brain-activity pattern that are considered as characteristic for aggressive cognitions and affects,” said René Weber, assistant professor of communication and telecommunication at MSU and a researcher on the project. “There is a neurological link and there is a short-term causal relationship. “Violent video games frequently have been criticized for enhancing aggressive reactions such as aggressive cognitions, aggressive affects or aggressive behavior. On a neurobiological level we have shown the link exists.” Weber conducted the research with his colleagues Klaus Mathiak of RWTH Aachen University (Germany) and Ute Ritterfeld of the University of Southern California. © 2005 Michigan State University Division of University Relations

Keyword: Aggression
Link ID: 8026 - Posted: 06.24.2010

Infants born with oxygen loss who are given an innovative therapy that lowers their entire body temperature by four degrees within the first six hours of life, have a better chance of survival and lower incidence of brain injury, according to a report in the October 13 issue of the New England Journal of Medicine. "We speculate that this therapy lowers the brain temperature as well as body temperature and slows down the injury process caused by birth asphyxia, which results in loss of oxygen to the brain," said Yale researcher Richard A. Ehrenkranz, M.D., professor of pediatric neonatology and obstetrics and gynecology at Yale School of Medicine and Yale-New Haven Hospital. "Less injury means a better outcome and fewer cases of cerebral palsy and other complications." Ehrenkranz co-authored the study with colleagues at 14 other institutions in the National Institute of Child Health and Human Development Neonatal Research Network. Hypoxic ischemic encephalopathy (HIE) occurs when an infant's brain fails to receive sufficient oxygen or blood before birth. The condition may occur hours before birth or during labor and delivery. It can be caused by complications such as compression or tearing of the placenta or the umbilical cord and rupture of the uterus. Many infants who survive HIE experience brain disability.

Keyword: Development of the Brain
Link ID: 8025 - Posted: 10.13.2005

Psychological stress early in life may lead to memory loss and mental decline in middle age, research suggests. A study on rats suggests infant stress has a negative impact on the way brain cells communicate with each other. The researchers believe parental loss, abuse or neglect may contribute to a type of memory loss in middle age more normally seen in the elderly. The study, by the University of California, Irvine, features in the Journal of Neuroscience. The California team highlighted problems in the signalling mechanism between cells in an area of the brain called the hippocampus, which is known to play a key role in learning and memory. Lead researcher Dr Tallie Baram said: "The loss of cognitive function later in life is probably a result of both genetic and environmental factors. While it is not yet possible to change a person's genetic background, it may be feasible to block the environmental effects, particularly of early life stress, on learning and memory later in life. These studies point to the development of new, more effective ways to prevent cognitive impairment later in life." The researchers induced stress in rats by limiting the nesting material in cages containing females and their new-born young. The young rats appeared to overcome their initial feelings of stress but during middle age started to show signs of memory lapses. (C)BBC

Keyword: Learning & Memory; Stress
Link ID: 8024 - Posted: 10.12.2005