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Heated tail display warns off would-be predators. MICHAEL HOPKIN Faced with an angry rattlesnake, you or I might freeze with fear. But California ground squirrels take the opposite approach: they heat their tails up to warn the snake that they will not take an attack lying down. It is the first time that an animal has been shown to send a deliberate signal using infrared radiation, or heat, says Aaron Rundus of the University of California, Davis, who presented the discovery on Monday at the Animal Behavior Society's annual meeting in Oaxaca, Mexico. Rattlesnakes are a constant menace to the squirrels, often poaching young from families. This threat gives rise to aggressive stand-offs between snakes and adult squirrels, in which the rodent kicks sand and brandishes its tail in a bid to harass the predator into submission. The snakes do much of their hunting by detecting heat, using sensitive structures called pit organs in their faces. The new discovery shows that the squirrels take advantage of this sensitivity by broadcasting their message in a language the snakes can understand. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Animal Communication; Vision
Link ID: 5663 - Posted: 06.24.2010

By Sherry Seethaler A discovery by a University of California, San Diego biologist that some species of bees exploit chemical clues left by other bee species to guide their kin to food provides evidence that eavesdropping may be an evolutionary driving force behind some bees’ ability to conceal communication inside the hive, using a form of animal language to encode food location. Bees can use two main forms of communication to tell their hive mates where to find food: abstract representations such as sounds or dances within the hive or scent markings outside the hive to mark the food and/or the route to it. In 1999, James Nieh, an assistant professor of biology at UCSD, published a paper in which he hypothesized communication within the hive may have evolved as a way of avoiding espionage by competitors. Nieh’s most recent study, a collaboration with Brazilian biologists published June 16 in the early on-line version of the journal Proceedings of the Royal Society, is strong support for that hypothesis because it shows that bees can indeed use the chemical markings deposited by bees of other species to home in on and take over their food source. The paper will appear in print in Proceedings of the Royal Society in August. Copyright ©2001 Regents of the University of California

Keyword: Animal Communication; Language
Link ID: 5662 - Posted: 06.24.2010

Sometimes it takes time to uncover nature's secrets. Take the case of callimicos, also called Goeldi's monkeys, a reclusive and diminutive South American primate. Discovered a century ago by Swiss naturalist Emil August Goeldi, the animals were once considered to be a possible "missing link" between small and large New World monkeys. But new findings from the first long-term studies of the monkeys in the wild seem to indicate that this is not the case, although the animals have a unique set of anatomical, reproductive and behavioral characteristics. Leila Porter, a biological anthropologist at the University of Washington, has spent nearly four years observing callimicos (Callimico goeldii) in the Amazon basin of Northern Bolivia. Her pioneering fieldwork has collected the first detailed data of the ecology and behavior of the animals, an endangered species, in the wild. Among other things, her observations show callimicos eat fungi during the dry season, making them the only tropical primate species to subsist on this food source for part of the year. They also have a different reproductive strategy from other small New World monkeys. Callimicos (Latin for beautiful little monkeys) have the capacity to give birth to a single offspring twice annually while their closest primate relatives – marmosets, tarmarins and lion tarmarins – give birth to twins once a year.

Keyword: Evolution
Link ID: 5661 - Posted: 06.24.2010

By ROB JORDAN In the early morning stillness, Michael Schroeder sits alone at his kitchen table and wonders who he is. Everyday, after his wife leaves for work, the 37-year-old tries to remember the once-familiar routines of a quiet life. What drawer do the socks go in? Where is the supermarket? Who are my friends? Almost a month after a passing motorist found him lying unconscious on the side of a lonely desert road in California, Schroeder still doesn't know how he got so far from home or why he wandered in the sand for two days without food, water or identification. He doesn't remember his name, where he's from or who his wife and 9-year-old son are. All he has are a handful of images from somewhere in his mind and his wife Sally's reassurance. "I know this is where we live, and I know this is my family," Schroeder said. "I can just put two and two together and figure things out intellectually." Police identified Schroeder after they traced the license plate on his abandoned pickup to a missing person report. A tattoo on his right shoulder - a heart with his wife's name on it - confirmed the link. Copyright © 2002 The Tuscaloosa News

Keyword: Learning & Memory
Link ID: 5660 - Posted: 06.24.2010

Brain Recordings Can Capture Thinking As It Happens By Sherry Seethaler A team led by University of California San Diego neurobiologists has developed a new approach to interpreting brain electroencephalograms, or EEGs, that provides an unprecedented view of thought in action and has the potential to advance our understanding of disorders like epilepsy and autism. The new information processing and visualization methods that make it possible to follow activation in different areas of the brain dynamically are detailed in a paper featured on the cover of the June 15 issue of the journal Public Library of Science Biology (plos.org) The significance of the advance is that thought processes occur on the order of milliseconds—thousandths of a second—but current brain imaging techniques, such as functional Magnetic Resonance Imaging and traditional EEGs, are averaged over seconds. This provides a “blurry” picture of how the neural circuits in the brain are activated, just as a picture of waves breaking on the shore would be a blur if it were created from the average of multiple snapshots. “Our paper is the culmination of eight years of work to find a new way to parse EEG data and identify the individual signals coming from different areas of the brain,” says lead author Scott Makeig, a research scientist in UCSD’s Swartz Center for Computational Neuroscience of the Institute for Neural Computation. Copyright ©2001 Regents of the University of California.

Keyword: Brain imaging
Link ID: 5659 - Posted: 06.24.2010

By LAURAN NEERGAARD, AP Medical Writer WASHINGTON - One after another, teenagers trickle into Dr. David Rothner's office with the same complaint: almost daily headaches, despite popping over-the-counter painkillers four, then six, then eight times a week. Many get a diagnosis of rebound headache, a vicious cycle where the more painkiller some people use, the more likely new headaches are to crop up between doses. Headache specialists say it's not uncommon for adults to fall into that trap, and Rothner's check of records at the Cleveland Clinic suggests a surprising number of teens and preteens may, too. Of 680 patients referred to the hospital's pediatric headache center, 22 percent were overusing nonprescription headache medicine — meaning at least three doses a week for more than six weeks. The worst was one patient who reached 28 doses in a single week. "We have a lot of kids that are overusing OTC medicine," warns Rothner, a Cleveland Clinic pediatric neurologist who presented the data to the American Headache Society last week. Overuse increases the risk of such side effects as stomach bleeding or kidney or liver damage, problems many people don't realize can occur even with over-the-counter drugs. Copyright © 2004 The Associated Press.

Keyword: Pain & Touch
Link ID: 5658 - Posted: 06.24.2010

Why some doctors are moving away from performing surgery on babies of indeterminate gender. By Claudia Kolker Approximately 10 times a year in Houston, at the birth of a certain type of baby, a special crisis team at Texas Children's Hospital springs into action. Assembled in 2001, the unusual team includes a psychologist, urologist, geneticist, endocrinologist, and ethicist. Its mission: to counsel parents of infants sometimes referred to as "intersex" babies—that is, babies of indeterminate physical gender. That such a team exists—and that it often counsels deferring surgery for infants who are otherwise healthy—reflects a radical new thinking among doctors about gender identity and outside efforts to shape it. Instead of surgically "fixing" such children to make them (visually, at least) either male or female, a handful of U.S. specialists now argue that such infants should be left alone and eventually be allowed to choose their gender identity. The approach challenges decades of conventional wisdom about what to do with infants whose genitalia don't conform to the "norm." Until very recently, such children were automatically altered with surgery, often with tragic consequences. Each year, about one in 2,000 children is born with ambiguous-looking genitalia. A wide range of disorders may be responsible—genetic defects, hormonal abnormalities, or unexplained developmental disruptions that occurred in utero. ©2004 Microsoft Corporation.

Keyword: Sexual Behavior; Development of the Brain
Link ID: 5657 - Posted: 06.24.2010

Researchers at the University of Maryland School of Medicine have found that that a low dose of aspirin or similar painkillers, equivalent to the dose a human would take for a headache, can interfere with the wiring of the developing brain. Male baby rats exposed to aspirin, either in the womb or by nursing, have lower-than-normal sex drives when they grow up. "The pregnant rat was exposed to aspirin in her water for the last week of pregnancy and the first week of breast-feeding," explains Margaret McCarthy professor of physiology at the University of Maryland School of Medicine. "This is a time of heightened sensitivity of the brain to determine if it's going to become male or female. When we raised those male pups to adulthood, they showed what we would call a mildly impaired sexual behavior." Scientists have known for a long time that aspirin and other nonsteroidal anti-inflammatory drugs stop pain and inflammation by blocking the body's production of a group of signaling molecules called prostaglandins. But nobody knew that prostaglandins might be involved in regulating sex behaviors. McCarthy and her colleague Stuart Amateau found that by blocking prostaglandin production, the aspirin actually changed the rats' brain wiring in a region that's also involved in controlling human sex behaviors. They reported their findings in the June 2004 issue of the journal Nature Neuroscience. © ScienCentral, 2000-2004.

Keyword: Sexual Behavior
Link ID: 5656 - Posted: 06.24.2010

CHICAGO – Eating fruit may help protect against the development of age-related maculopathy (ARM), an eye disease that can cause blindness, according to an article in the June issue of The Archives of Ophthalmology, one of the JAMA/Archives journals. According to information in the article, ARM is the leading cause of vision loss among people 65 and older. Because there are no effective treatments for ARM, prevention of this eye disease is important. Antioxidant vitamin and mineral supplementation has been found to help protect against ARM. In a recent study, supplementation with high-doses of vitamins C and E, beta carotene and zinc delayed the progression of ARM. Eunyoung Cho, Sc.D., of Brigham and Women's Hospital, Boston, and colleagues examined the effect of antioxidant vitamins and carotenoids (compounds responsible for the red, yellow and orange pigments found in some fruits and vegetables) as well as fruits and vegetables on the development of ARM among 77,562 women and 40,866 men. The women were part of the Nurses' Health Study, and the men were participants in the Health Professionals Follow-up Study. Participants were at least 50 years old at the beginning of the study with no diagnosis of ARM. Women were followed for up to 18 years, and men were followed for up to 12 years.

Keyword: Vision
Link ID: 5655 - Posted: 06.24.2010

The initial trial of a controversial method for treating spinal cord injuries within two weeks of an accident suggests it may be partly successful. More patients recovered some sensation and movement than would normally be expected, the company behind the trial claims. Independent experts say the results look promising, but caution that with just 16 people treated so far, it is too early to draw any conclusions. Some worry that the technique is risky and could cause serious problems in the long term. The method involves extracting immune cells from a patient's blood, "activating" them by incubating them with skin cells, and then injecting the cells directly into the damaged spinal cord. This must all be done within 14 days of the injury, so even if larger trials confirm its benefits, the method will not help the hundreds of thousands of people worldwide with existing injuries. The technique is being developed by ProNeuron Biotechnologies of Los Angeles, California, which has just submitted results from the first 10 patients for publication. All patients fell into the most severe spinal injury category, called ASIA-A. This is defined as having no sensation or ability to move below the site of injury. Normal sensation and movement is defined as ASIA-E. © Copyright Reed Business Information Ltd.

Keyword: Regeneration
Link ID: 5654 - Posted: 06.24.2010

Testosterone damps pain sensation in males. LAURA NELSON It will come as no surprise to some... men are less sensitive than women, at least to pain. Researchers have found that the male hormone testosterone masks feelings of discomfort. They believe that such tolerance effects may help men to maintain their stamina in fights, when testosterone levels are high. "If men are less sensitive to pain, there is more willingness to fight and participate in further fights," says Michaela Hau, an animal physiology and behaviour scientist at Princeton University, New Jersey, and lead author of the study. The research team gave testosterone implants to male sparrows and measured their reaction times to pain. Testosterone allowed the birds to tolerate discomfort for longer periods, suggesting that the hormone somehow disguises pain. They determined the normal pain threshold of male sparrows by dangling one of their legs in a beaker of hot water and varying the temperature. "We measured how long it took for the bird to retract its leg," says Hau. The quicker the birds removed their legs, the more pain they were presumably feeling. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Pain & Touch; Hormones & Behavior
Link ID: 5653 - Posted: 06.24.2010

Eight-limbed creatures have a favourite. MICHAEL HOPKIN Most octopuses have a favourite arm, zoologists have discovered. This is the first time they have been found to show any bias when choosing which of their eight limbs is right for the job. The creatures use their trusty first-choice appendage when exploring a new nook or cranny, says Ruth Byrne of the University of Vienna in Austria. She presented the discovery on Sunday at the annual meeting of the Animal Behavior Society in Oaxaca, Mexico. In terms of skill, octopus arms are created pretty much equal. "All eight arms are capable of the same tasks," Byrne told the meeting. "There's hardly any specialization." This had prompted experts to suspect that the creatures simply use whichever arm is handiest. Indeed, one of their preferred hunting strategies is to jump on top of a rock and curl all of their arms underneath, grabbing whatever they find. © Nature News Service / Macmillan Magazines Ltd 2004

Keyword: Laterality
Link ID: 5652 - Posted: 06.24.2010

Adults often struggle trying to learn a second language, but the process may not be as tedious and slow as commonly believed. University of Washington researchers who followed college students learning first-year French have found that the students' brain activity was clearly discriminating between real and pseudo-French words after only 14 hours of classroom instruction. At the same time, however, the students performed at 50-50 levels when asked to consciously choose whether or not the stimuli were real French words. In addition, the researchers found that as the students had more exposure to French, the difference in brain response to words and pseudo words became larger. The study, which is one of the first to look at how fast second-language words are learned and how the brain responds to words with increasing experience with the new language, was published June 13 in the on-line edition of the journal Nature Neuroscience. The research team was headed by Judith McLaughlin, a UW research scientist, and Lee Osterhout, an associate professor of psychology. "Age and reduced brain plasticity are the classic reasons usually given for difficulty in learning a second language. But almost all thinking about this concerns syntax and grammar, while word learning has been ignored," Osterhout said. "Our results clearly show there are aspects of a second language that can be learned quickly and with amazing ease. A number of our subjects told us they hadn't been studying that hard because the course had just begun or because they were taking French to simply fulfill their language requirement. What's remarkable, considering those factors and that the language wasn't being taught in an immersion environment, was that we saw this rapid change in brain activity."

Keyword: Language
Link ID: 5651 - Posted: 06.15.2004

New Haven, Conn. -- The principal active ingredient in marijuana causes transient schizophrenia-like symptoms ranging from suspiciousness and delusions to impairments in memory and attention, according to a Yale research study. Lead author D. Cyril D'Souza, M.D., associate professor of psychiatry at Yale School of Medicine, said the study was an attempt to clarify a long known association between cannabis and psychosis in the hopes of finding another clue about the pathophysiology of schizophrenia. "Just as studies with amphetamines and ketamine advanced the notion that brain systems utilizing the chemical messengers dopamine and NMDA receptors may be involved in the pathophysiology in schizophrenia, this study provides some tantalizing support for the hypotheses that the brain receptor system that cannabis acts on may be involved in the pathophysiology of schizophrenia," he said. "Clearly, further work is needed to test this hypothesis." D'Souza and his co-researchers administered various doses of delta-9-THC, the main active ingredient in cannabis, to subjects who were screened for any vulnerability to schizophrenia. Some subjects developed symptoms resembling those of schizophrenia that lasted approximately one half hour to one hour. These symptoms included suspiciousness, unusual thoughts, paranoia, thought disorder, blunted affect, reduced spontaneity, reduced interaction with the interviewer, and problems with memory and attention.

Keyword: Drug Abuse
Link ID: 5650 - Posted: 06.15.2004

Implications for future treatment of cerebral palsy and epilepsy An existing drug already approved by the FDA may protect newborns from brain injury and long-term neurologic problems caused by excitotoxicity, or over-activation of neurons, report two NIH-funded studies from Children's Hospital Boston. The drug, topiramate, is currently approved to control seizures in adults and in children over age 3, but the findings may provide the basis for a protective therapy that could be given to babies immediately after traumatic birth events that compromise the brain's blood and oxygen supply. Such events can cause long-term neurologic abnormalities that underlie serious conditions like cerebral palsy and epilepsy. Premature infants, who are surviving in greater numbers, are especially vulnerable to excitotoxicity. When the brain's blood and oxygen supply are compromised, a condition known as hypoxia-ischemia, the chemical glutamate accumulates in brain tissues. Glutamate binds to receptors on neurons and over-activates them, causing the brain cells to die. The Children's Hospital researchers, led by Dr. Frances Jensen, have found that the neurons of premature infants and other newborns have more glutamate receptors than the adult brain, making them very vulnerable to excitotoxic brain injury from hypoxia-ischemia. In two studies, they investigated whether compounds that block a certain type of glutamate receptor, known as AMPA, can dampen the harmful effects of excitotoxicity in the immature brain.

Keyword: Epilepsy; Development of the Brain
Link ID: 5649 - Posted: 06.15.2004

Scientists have shown that there is a degree of truth in the old adage that love is blind. They have found that feelings of love lead to a suppression of activity in the areas of the brain controlling critical thought. It seems that once we get close to a person, the brain decides the need to assess their character and personality is reduced. The study, by University College London, is published in NeuroImage. The researchers found that both romantic love and maternal love produce the same effect on the brain. They suppress neural activity associated with critical social assessment of other people and negative emotions. The UCL team scanned the brains of 20 young mothers while they viewed pictures of their own children, children they were acquainted with, and adult friends. The team found that the patterns of brain activity were very similar to those identified in an earlier study looking at the effects of romantic love. (C)BBC

Keyword: Sexual Behavior; Brain imaging
Link ID: 5648 - Posted: 06.14.2004

A vaccine which can help cocaine addicts break their addiction has been developed by a UK pharmaceutical company. Trials carried out in the US showed almost half of those given the TA-CD vaccine, developed by Xenova, were able to stay of the drug for six months. The vaccine does not stop the craving for cocaine, but will stop addicts experiencing a high when they take it. The company says this prevents the people becoming re-addicted. In the study, the TA-CD vaccine was compared with a dummy version. David Oxlade, chief executive of Xenova, told BBC Radio 4's Today programme: "This is the third study in the US that we are reporting on today, and it shows that almost half the addicts were able to stay cocaine-free for six months. "That is a quite remarkable position." (C)BBC

Keyword: Drug Abuse
Link ID: 5647 - Posted: 06.14.2004

By LEE JENKINS In the four-tenths of a second it takes for a 101-mile-an-hour fastball to fly from the pitcher’s hand to home plate, the San Francisco Giants slugger Barry Bonds sizes up the seams and gauges the spin, projects where the ball is headed and decides what he wants to do with it. One night this season, Bonds used this sliver of time to plant his right foot, jackhammer his hips and thrust his hands so violently that he got completely around on the triple-digit baseball and yanked the ball out of the stadium, about 60 feet foul. Around SBC Park in San Francisco, fans seemed torn between applauding the blow and debating it. In a press-box seat, one reporter said to another, “Steroids can’t do that.” And, inevitably, the response rang out: “How do you know?” Such is the interchange defining a sport divided — between those who speculate about the role of steroids in every game, and those in awe over a Bonds blast or some utility infielder’s opposite-field home run. Copyright 2004 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 5646 - Posted: 06.24.2010

People are woefully bad at recalling details of their own traumatic experiences. When military personnel were subjected to threatening behaviour during mock interrogations, most failed to identify the questioner a day or so later, and many even got the gender wrong. The finding casts serious doubt on the reliability of victim testimonies in cases involving psychological trauma. Numerous studies have questioned the accuracy of recall of traumatic events, but the research is often dismissed as artificial and not intense enough to simulate real-life trauma. Other studies have suggested that intense, personal experiences might produce near photographic recollection, something that prosecutors and juries in legal cases often assume. But some researchers think this is an illusion. "People come away from these experiences feeling they will never forget what happened," says Gary Wells, an expert on eyewitness testimony at Iowa State University in Ames, "but they confuse that with thinking they remember the details." © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory; Stress
Link ID: 5645 - Posted: 06.24.2010

WASHINGTON — Most will agree that two heads are better than one in solving problems. The same logic may be true for language and retaining cognitive processes as we age. Being fluent in two languages seems to prevent some of the cognitive decline seen in same-age monolingual speaking persons, according to the findings of a study appearing in this month’s journal of Psychology and Aging. It is established that learned knowledge and habitual procedures (crystallized intelligence) hold up well as people age, said lead author Ellen Bialystok, Ph.D., of York University, but abilities that depend on keeping one’s attention on a task (fluid intelligence) actually decline as people get older. But in her study, Bialystok found that those who have been bilingual most of their life were better able to manage their attention to complex set of rapidly changing task demands as measured by an experimental task – The Simon Task – that purposely distracts the test takers. Three studies compared the performance of a total of 104 monolingual and bilingual middle-aged (30-59 year olds) and 50 older adults (60-88 year olds) on the Simon Task. The Simon task measures reaction time without the subjects having to be familiar with the content, and it measures aspects of cognitive processing that decline with age, according to the study. © 2004 American Psychological Association

Keyword: Language; Alzheimers
Link ID: 5644 - Posted: 06.24.2010