By Bruce Bower In one scene of the 1999 movie The Blair Witch Project, three film students searching for a legendary creature hike for hours only to end up at the spot where they had started. Their misfortune is not just a suspenseful twist in a fictional world, says psychologist Jan Souman of the Max Planck Institute for Biological Cybernetics in Tübingen, Germany. Given no external cues to direction, people trying to walk straight over unfamiliar terrain end up doing intermittent loop-de-loops, Souman and his colleagues report in a paper published online August 20 in Current Biology. Circular walking occurs when people have to rely solely on bodily cues, such as rotational shifts and joint movements, to estimate the location of “straight ahead,” Souman hypothesizes. As random errors in bodily feedback accumulate, a person eventually drifts to one side or the other. A walker dependent on bodily cues may first make a circle to the right, drift back to a straight-ahead direction, start to zigzag and then make a circle to the left. “You may think that you’re walking in a straight line, but in fact the direction you’re walking in is drifting more and more away from straight ahead, making you walk in circles,” Souman says. © Society for Science & the Public 2000 - 2009

Keyword: Miscellaneous
Link ID: 13191 - Posted: 06.24.2010

By Jenny Lauren Lee Nostrils usually get along great. But when they smell conflicting scents, those nose holes become deadly rivals. When one nostril smells something different from the other, the brain chooses between the two scents instead of combining them, researchers report online August 20 in Current Biology. The authors argue that their study is the first to demonstrate this phenomenon, which they call two-nostril, or binaral, rivalry. Studying the rivalry between the nares may help scientists understand how the brain processes smells, says study coauthor Denise Chen of Rice University in Houston. “It’s an interesting article,” says neuroscientist Jay Gottfried of Northwestern University in Evanston, Ill. “It shows something that has not been appreciated much before.” Scientists have known about rivalry between the eyes and between the ears for years. When a subject’s right eye views an image that is incompatible with the image that the left eye views, the subject reports seeing the images alternating rather than superimposed upon each other. Similarly, in two-ear rivalry, when each ear hears a different tone, the brain switches back and forth between them. To test whether the same phenomenon exists for smell, Chen and Rice University colleague Wen Zhou exposed12 volunteers to two different scents, one in each nostril. One nostril was connected by a tube to a bottle of phenylethyl alcohol, which smells like rose petals. The other was connected to a bottle of n-butanol, which pongs of marker pen. During each whiff, the volunteers breathed in both scents. © Society for Science & the Public 2000 - 2009

Keyword: Chemical Senses (Smell & Taste)
Link ID: 13190 - Posted: 06.24.2010

By Katherine Harmon Humans have long enjoyed crowing about their intellectual superiority in the animal kingdom. But just as some studies—of tool-wielding birds and language-discerning rodents—have begun to chip away at our cognitive place in the sun, others have set their sights on two human groups whose intelligence might have been underestimated—the very young and the very old. Babies first: "Generations of psychologists and philosophers have believed that babies and young children were basically defective adults—irrational, egocentric and unable to think logically," Alison Gopnik, author of The Philosophical Baby (Farrar, Straus, and Giroux, 2009), wrote in a New York Times editorial last week. But her research—and that of others—has gone on to show that rather than being one crayon short of a full box, "In some ways, they are smarter than adults," she says. Gopnik's research at the University of California, Berkeley, has shown young children (of the 5-and-under set) to be fully capable of reasoning and assessing probability. But babies' tendency to be interested in just about everything has led many adults to assume their lack of focus is indicative of unintelligence, Gopnik noted. "Babies explore; adults audit," she says. On the other end of the spectrum, even older adults without an impairing disease such as Alzheimer's are often assumed to have experienced some cognitive slippage. While that may be true in some respects, new research is proving that seniors are perfectly competent in learning new concepts—and remembering them. © 1996-2009 Scientific American Inc.

Keyword: Development of the Brain
Link ID: 13189 - Posted: 06.24.2010

by Carl Zimmer Some of the common words we use are frozen mistakes. The term influenza comes from the Italian word meaning “influence”—an allusion to the influence the stars were once believed to have on our health. European explorers searching for an alternate route to India ended up in the New World and uncomprehendingly dubbed its inhabitants indios, or Indians. Neuroscientists have a frozen mistake of their own, and it is a spectacular blunder. In the mid-1800s researchers discovered cells in the brain that are not like neurons (the presumed active players of the brain) and called them glia, the Greek word for “glue.” Even though the brain contains about a trillion glia—10 times as many as there are neurons—the assumption was that those cells were nothing more than a passive support system. Today we know the name could not be more wrong. Glia, in fact, are busy multitaskers, guiding the brain’s development and sustaining it throughout our lives. Glia also listen carefully to their neighbors, and they speak in a chemical language of their own. Scientists do not yet understand that language, but experiments suggest that it is part of the neurological conversation that takes place as we learn and form new memories. If you had to blame one thing for the mistaken impression about glia, it would have to be electricity. The 18th-century physiologist Luigi Galvani discovered that if he touched a piece of electrified metal to an exposed nerve in a frog’s leg, the leg twitched. He and others went on to show that a slight pulse of electricity moving through the metal to the nerve was responsible. For two millennia physicians and philosophers had tried to find the “animal spirits” that moved the body, and Galvani discovered that impetus: It was the stuff of lightning.

Keyword: Glia
Link ID: 13188 - Posted: 06.24.2010

By Constance Holden Nerds of the world, take heart. Brainy male birds have more luck with females than do their less-intelligent counterparts, according to a study of the Australian bowerbird. Researchers claim this is the first study to show a link between smarts and mating success in any species. It's hard to find a bird with a more complex and energetic courtship behavior than the bowerbird. At breeding season, males build a special platform, or bower, on the forest floor to lure females, and they decorate it with rare objects such as blue feathers and shiny bits of glass. They accompany this with varied vocalizations, hopping, and tail-bobbing. These behaviors help male bowerbirds attract mates, but are the females also looking for a guy with brains? To find out, researchers at the University of Maryland, College Park, mucked with about 30 bowers they found at Wallaby Creek in Australia. Graduate student Jason Keagy took advantage of males' dislike of having red objects in their bowers (they much prefer blue, apparently because of its rarity in natural settings). In one test, he placed a red plastic battery terminal cover in a bower and covered it with a transparent box that the birds had to tip and drag off; in another, he fixed red tiles in the bowers with screws, forcing the birds to try to cover them up with leaves and twigs. The team then used automated video cameras to monitor the bowers. The best problem-solvers scored the most copulations, the team reports online this month in the journal Animal Behaviour. © 2009 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Intelligence
Link ID: 13187 - Posted: 06.24.2010

by Kathleen McGowan Rita Magil was driving down a Montreal boulevard one sunny morning in 2002 when a car came blasting through a red light straight toward her. “I slammed the brakes, but I knew it was too late,” she says. “I thought I was going to die.” The oncoming car smashed into hers, pushing her off the road and into a building with large cement pillars in front. A pillar tore through the car, stopping only about a foot from her face. She was trapped in the crumpled vehicle, but to her shock, she was still alive. The accident left Magil with two broken ribs and a broken collarbone. It also left her with post-traumatic stress disorder (PTSD) and a desperate wish to forget. Long after her bones healed, Magil was plagued by the memory of the cement barriers looming toward her. “I would be doing regular things—cooking something, shopping, whatever—and the image would just come into my mind from nowhere,” she says. Her heart would pound; she would start to sweat and feel jumpy all over. It felt visceral and real, like something that was happening at that very moment. Most people who survive accidents or attacks never develop PTSD. But for some, the event forges a memory that is pathologically potent, erupting into consciousness again and again. “PTSD really can be characterized as a disorder of memory,” says McGill University psychologist Alain Brunet, who studies and treats psychological trauma. “It’s about what you wish to forget and what you cannot forget.” This kind of memory is not misty and water­colored. It is relentless.

Keyword: Learning & Memory
Link ID: 13186 - Posted: 06.24.2010

Bats, birds, box turtles, humans and many other animals share at least one thing in common: They sleep. Humans, in fact, spend roughly one-third of their lives asleep, but sleep researchers still don't know why. According to the journal Science, the function of sleep is one of the 125 greatest unsolved mysteries in science. Theories range from brain "maintenance" - including memory consolidation and pruning - to reversing damage from oxidative stress suffered while awake, to promoting longevity. None of these theories are well established, and many are mutually exclusive. Now, a new analysis by Jerome Siegel, UCLA professor of psychiatry and director of the Center for Sleep Research at the Semel Institute for Neuroscience and Human Behavior at UCLA and the Sepulveda Veterans Affairs Medical Center, has concluded that sleep's primary function is to increase animals' efficiency and minimize their risk by regulating the duration and timing of their behavior. The research appears in the current online edition of the journal Nature Reviews Neuroscience. "Sleep has normally been viewed as something negative for survival because sleeping animals may be vulnerable to predation and they can't perform the behaviors that ensure survival," Siegel said. These behaviors include eating, procreating, caring for family members, monitoring the environment for danger and scouting for prey. "So it's been thought that sleep must serve some as-yet unidentified physiological or neural function that can't be accomplished when animals are awake," he said.

Keyword: Sleep; Evolution
Link ID: 13185 - Posted: 08.22.2009

By BENEDICT CAREY The safest and most effective treatment for hard-core heroin addicts who fail to control their habit using methadone or other treatments may be their drug of choice, in prescription form, researchers are reporting after the first rigorous test of the approach performed in North America. For years, European countries like Switzerland and the Netherlands have allowed doctors to provide some addicts with prescription heroin as an alternative to buying drugs on the street. The treatment is safe and keeps addicts out of trouble, studies have found, but it is controversial — not only because the drug is illegal but also because policy makers worry that treating with heroin may exacerbate the habit. The study, appearing in the current issue of the New England Journal of Medicine, may put some of those concerns to rest. “It showed that heroin works better than methadone in this population of users, and patients will be more willing to take it,” said Dr. Joshua Boverman, a psychiatrist at Oregon Health and Science University in Portland. Perhaps the biggest weakness of methadone treatment, Dr. Boverman said, is that “many patients don’t want to take it; they just don’t like it.” In the study, researchers in Canada enrolled 226 addicts with longstanding habits who had failed to improve using other methods, including methadone maintenance therapy. Doctors consider methadone, a chemical cousin to heroin that prevents withdrawal but does not induce the same high, to be the best treatment for narcotic addiction. A newer drug, buprenorphine, is also effective. Copyright 2009 The New York Times Company

Keyword: Drug Abuse
Link ID: 13184 - Posted: 06.24.2010

By Tom Heneghan, Religion Editor PHILADELPHIA (Reuters) - Buddhist monks and Catholic nuns boost their brain power through meditation and prayer, but even atheists can enjoy the mental benefits that believers derive from faith, according to a popular neuroscience author. The key, Andrew Newberg argues in his new book "How God Changes Your Brain," lies in the concentrating and calming effects that meditation or intense prayer have inside our heads. Brain scanners show that intense meditation alters our gray matter, strengthening regions that focus the mind and foster compassion while calming those linked to fear and anger. Whether the meditator believes in the supernatural or is an atheist repeating a mantra, he says, the outcome can be the same - a growth in the compassion that virtually every religion teaches and a decline in negative feelings and emotions. "In essence, when you think about the really big questions in life -- be they religious, scientific or psychological -- your brain is going to grow," says Newberg, head of the Center for Spirituality and the Mind at the University of Pennsylvania. "It doesn't matter if you're a Christian or a Jew, a Muslim or a Hindu, or an agnostic or an atheist," he writes in the book written with Mark Robert Waldman, a therapist at the Center. © Thomson Reuters 2009

Keyword: Emotions
Link ID: 13183 - Posted: 06.24.2010

Many people do not realise drinking alcohol can disturb a good night's sleep by interfering with the brain, a government-funded poll suggests. Almost half of 2,000 drinkers surveyed reported fatigue the day after drinking more than the recommended daily limit. But some 58% of those questioned were unaware that sleep problems could be caused by exceeding the limit. The survey by YouGov was carried out for the Know Your Limits campaign, started three years ago. Men are advised to drink no more than four units a day - the equivalent of two pints of regular-strength beer, and women no more than three units - the equivalent of a large, 250ml glass of wine. According to the poll's findings, many people did not know that the dehydration caused by drinking could interfere with their sleep. Alcohol stops the brain from releasing vasopressin, a chemical which tells the kidneys to reabsorb water that would otherwise end up in the bladder. Without this signal, the drinker needs more frequent trips to the toilet. The loss of this water can also lead to a headache emanating from the inner lining of the skull. In addition, alcohol disrupts the "REM" stage of sleep, which is thought necessary for a deep and effective slumber. After drinking the body tends to fall straight into a deep sleep, and only enters the REM stage once the alcohol has been metabolised. As the body wakes more easily from REM sleep, many drinkers find they stir early in the morning without feeling as if they have slept properly. (C)BBC

Keyword: Drug Abuse; Sleep
Link ID: 13182 - Posted: 08.20.2009

by Veronique Greenwood In a famous set of experiments in the 1970s, children were observed trick-or-treating in the suburbs. Some were asked their names and addresses upon arriving at a door, while some were asked nothing. All were instructed to take just one piece of candy from the bowl, but as soon as the owner of the home retreated into the kitchen, the children who hadn’t provided their names and addresses shoveled the candy into their bags, sometimes taking everything in the bowl. Psychologists posited that anonymity made the children feel safe from the repercussions of their actions, an effect they call deindividuation. Moral psychologists have since constructed myriad experiments to probe the workings of human morality, studying how we decide to cheat or to play by the rules, to lie or to tell the truth. And the results can be surprising, even disturbing. For instance, we have based our society on the assumption that deciding to lie or to tell the truth is within our conscious control. But Harvard’s Joshua Greene and Joseph Paxton say this assumption may be flawed and are probing whether honesty may instead be the result of controlling a desire to lie (a conscious process) or of not feeling the temptation to lie in the first place (an automatic process). “When we are honest, are we honest because we actively force ourselves to be? Or are we honest because it flows naturally?” Greene asks. Greene and Paxton have just published a study in the Proceedings of the National Academy of Sciences that attempts to get at the subconscious underpinnings of morality by recording subjects’ brain activity as they make a decision to lie. Under the fMRI, subjects were asked to predict the result of a coin toss and were allowed to keep their predictions to themselves until after the coin fell, giving them a chance to lie. As motivation, they were paid for correct predictions. ©2005-2009 Seed Media Group LLC

Keyword: Emotions; Stress
Link ID: 13181 - Posted: 06.24.2010

By Marc Hauser * Charles Darwin argued that a continuity of mind exists between humans and other animals, a view that subsequent scholars have supported. * But mounting evidence indicates that, in fact, a large mental gap separates us from our fellow creatures. Recently the author identified four unique aspects of human cognition. * The origin and evolution of these distinctive mental traits remain largely mysterious, but clues are emerging slowly. Not too long ago three aliens descended to Earth to evaluate the status of intelligent life. One specialized in engineering, one in chemistry and one in computation. Turning to his colleagues, the engineer reported (translation follows): “All of the creatures here are solid, some segmented, with capacities to move on the ground, through the water or air. All extremely slow. Unimpressive.” The chemist then commented: “All quite similar, derived from different sequences of four chemical ingredients.” Next the computational expert opined: “Limited computing abilities. But one, the hairless biped, is unlike the others. It exchanges information in a manner that is primitive and inefficient but remarkably different from the others. It creates many odd objects, including ones that are consumable, others that produce symbols, and yet others that destroy members of its tribe.” “But how can this be?” the engineer mused. “Given the similarity in form and chemistry, how can their computing capacity differ?” “I am not certain,” confessed the computational alien. “But they appear to have a system for creating new expressions that is infinitely more powerful than those of all the other living kinds. I propose that we place the hairless biped in a different group from the other animals, with a separate origin, and from a different galaxy.” The other two aliens nodded, and then all three zipped home to present their report. © 1996-2009 Scientific American Inc

Keyword: Evolution
Link ID: 13180 - Posted: 06.24.2010

By Katherine Harmon If love is said to come from the heart, what about hate? Along with music, religion, irony and a host of other complex concepts, researchers are on the hunt for the neurological underpinnings of hatred. Functional magnetic resonance imaging (fMRI) has begun to reveal how the strong emotion starts to emerge in the brain. Neurobiologist Semir Zeki, of University College London's Laboratory of Neurobiology, led a study last year that scanned the brains of 17 adults as they gazed at images of a person they professed to hate. Across the board, areas in the medial frontal gyrus, right putamen, premotor cortex and medial insula activated. Parts of this so-called "hate circuit," the researchers noted, are also involved in initiating aggressive behavior, but feelings of aggression itself—as well as anger, danger and fear—show different patterns in the brain than hatred does. Certainly loathing can spring from positive feelings, such as romantic love (in the guise of a former partner or perceived rival). But love seems to deactivate areas traditionally associated with judgment, whereas hatred activates areas in the frontal cortex that may be involved in evaluating another person and predicting their behavior. Some commonalities with love, however, are striking, the study authors note. The areas of the putamen and insula that are activated by individual hate are the same as those for romantic love. "This linkage may account for why love and hate are so closely linked to each other in life," they wrote in the October 2008 PLoS ONE. © 1996-2009 Scientific American Inc

Keyword: Emotions; Brain imaging
Link ID: 13179 - Posted: 06.24.2010

By Jeanna Bryner A social snub can deliver a seemingly painful blow. Now, it turns out that sting may be real. A gene linked with physical pain is also associated with a person's sensitivity to rejection, a new study finds. The discovery doesn't suggest that being chosen last for a pick-up ball game, say, will send you limping off the field. Rather, a rare form of the so-called mu-opioid receptor gene (OPRM1) is likely involved in the emotional aspect of physical pain — essentially, how much a person is bothered by a throbbing leg, for instance. In the study, 122 participants indicated how much they agreed or disagreed with statements, such as "I am very sensitive to any signs that a person might not want to talk to me." Their saliva was also analyzed for OPRM1. Then, the researchers used functional magnetic resonance imaging (fMRI) to scan the brains of 31 of the participants during a virtual ball-tossing game. Initially, each participant was included with two virtual players before being excluded when the virtual players stopped throwing the ball to them. Individuals with the rare OPRM1 variant were more sensitive to social rejection. The mutant-gene carriers also showed more activity in brain regions linked with physical and social pain, including the dorsal anterior cingulate cortex and anterior insula. © 2009 LiveScience.com.

Keyword: Pain & Touch; Genes & Behavior
Link ID: 13178 - Posted: 06.24.2010

By Shankar Vedantam Gail Nichols has suffered from depression for years. When the 49-year-old resident of St. Marys, Kan., cannot sleep, she falls back on a form of entertainment that is gaining increasing credibility as a medical intervention: video games. Nichols said she discovered the mental health benefits of video games some years ago during a particularly bad spell of depression. She had just started playing a game called Bejeweled, which requires players to move gems into rows based on their color. When she could not get to sleep one night and was tormented by mental pain, she said, she turned on the computer and played the game for hours. "In the day, you can find someone to talk to," Nichols said. "Games are a big help in getting through to the next morning." Nichols liked the game so much that she got in touch with the manufacturer, PopCap Games. The inventors of the game were surprised to hear about its possible mental health benefits, and the company decided to study Bejeweled's untapped potential systematically. In a preliminary study that PopCap commissioned and funded, researchers found that volunteers who played Bejeweled displayed improved mood and heart rhythms compared with volunteers who weren't playing. The preliminary study was published this year in the Annual Review of Cybertherapy and Telemedicine. Now, the company is about to launch a second phase of testing to see if the video games can have measurable effects on clinical markers of depression. © 2009 The Washington Post Company

Keyword: Depression; Stress
Link ID: 13177 - Posted: 06.24.2010

By Sudeep Chand A study has shown that having a particular gene variant causes some macaque monkeys to drink more alcohol in experiments. The gene, known as the corticotrophin releasing factor (CRF) gene, is an important part of how we respond to everyday stress. Sometimes it can become overactive and lead to stress-related problems such as anxiety, depression and alcoholism. The findings may eventually lead to new treatments for alcoholism. Writing in the Proceedings of the National Academy of Sciences (PNAS), the scientists found that some monkeys with the gene variant drank more alcohol, possibly to relieve their anxiety. In particular the "T" form of the gene was associated with increased voluntary consumption of alcohol in drinks equivalent to the strength of strong beer. Some were drinking "well over the limit, maybe up to four or five drinks in one hour. They're not drinking it because it's tasty, it smelt like rubbing alcohol. And they act much like humans do: some sleep, some are friendly, others are aggressive," said Christina Barr, from the US National Institutes of Health in Bethesda, Maryland, one of the authors of the study. (C)BBC

Keyword: Drug Abuse; Genes & Behavior
Link ID: 13176 - Posted: 08.18.2009

By Christof Koch Do you think that your newest ac­quisition, a Roomba robotic vacuum cleaner that traces out its unpredictable paths on your living room floor, is conscious? What about that bee that hovers above your marmalade-covered breakfast toast? Or the newborn who finally fell asleep after being suckled? Nobody except a dyed-in-the-wool nerd would think of the first as being sentient; adherents of Jainism, India’s oldest religion, ­believe that bees—and indeed all living creatures, small and large—are aware; whereas most everyone would accord the magical gift of consciousness to the baby. The truth is that we really do not know which of these organisms is or is not conscious. We have strong feelings about the matter, molded by tradition, religion and law. But we have no objective, rational method, no step-by-step procedure, to determine whether a given organism has subjective states, has feelings. The reason is that we lack a coherent framework for consciousness. Although consciousness is the only way we know about the world within and around us—shades of the famous Cartesian deduction cogito, ergo sum—there is no agreement about what it is, how it relates to highly organized matter or what its role in life is. This situation is scandalous! We have a detailed and very successful framework for ­matter and for energy but not for the mind-body problem. This dismal state of ­affairs might be about to change, however. The universal lingua franca of our age is information. We are used to the idea that stock and bond prices, books, photographs, movies, music and our genetic makeup can all be turned into data streams of zeros and ones. These bits are the elemental atoms of information that are transmitted over an Ethernet cable or via wireless, that are stored, replayed, copied and assembled into gigantic repositories of knowledge. Information does not depend on the substrate. The same information can be represented as lines on paper, as electrical charges inside a PC’s memory banks or as the strength of the synaptic connections among nerve cells. © 1996-2009 Scientific American Inc.

Keyword: ADHD
Link ID: 13175 - Posted: 06.24.2010

By Lucas Laursen Despite thousands of years of domestication, dogs have a hard time figuring out what humans are thinking. That's the conclusion of a new study, which shows that dogs continue to trust unreliable people and therefore lack a so-called theory of mind. Humans don't start out with a theory of mind. Ask a toddler if his mother knows where he has hidden a toy, for example, and he'll likely say "yes," even if his mom has no idea. That's because the child assumes his mother knows everything he does; he doesn't have a real insight into what she's thinking. As the child grows up, however, he will begin to understand what his mother does and doesn't know, and will thus indicate that, "No, Mommy doesn't know where I hid the toy." Showing theory of mind in nonhumans has proven much more difficult. A 1978 study claimed to have identified a rudimentary theory of mind in chimpanzees by showing that they could anticipate the intentions of another animal. But later work was less conclusive. More recently, Alexandra Horowitz of Barnard College in New York City found that dogs ensure that they have other dogs' attention before playing with them. They also nip at distracted dogs to regain their attention, suggesting that dogs may have theory of mind when it comes to other dogs. To test dogs' theory of mind when it comes to humans, psychologist William Roberts and colleagues at the University of Western Ontario in Canada matched 24 dogs ranging in size from dachshunds to vizslas with both helpful and deceptive people. The team sat each dog near a tree in a park and placed two buckets at a distance; both smelled like food but only one contained it--a frankfurter. Sometimes a helpful human called the dog and pointed at the food-filled bucket. Other times, a deceptive human directed the dog to the empty bucket. If the dog fell for the ruse, the deceiver pretended to eat the sausage in order to ensure that the dog understood that it had missed a chance for a meal. © 2009 American Association for the Advancement of Science

Keyword: Animal Communication; Language
Link ID: 13174 - Posted: 06.24.2010

By NATALIE ANGIER If after a few months’ exposure to our David Lynch economy, in which housing markets spontaneously combust, coworkers mysteriously disappear and the stifled moans of dying 401(k) plans can be heard through the floorboards, you have the awful sensation that your body’s stress response has taken on a self-replicating and ultimately self-defeating life of its own, congratulations. You are very perceptive. It has. As though it weren’t bad enough that chronic stress has been shown to raise blood pressure, stiffen arteries, suppress the immune system, heighten the risk of diabetes, depression and Alzheimer’s disease and make one a very undesirable dinner companion, now researchers have discovered that the sensation of being highly stressed can rewire the brain in ways that promote its sinister persistence. Reporting earlier this summer in the journal Science, Nuno Sousa of the Life and Health Sciences Research Institute at the University of Minho in Portugal and his colleagues described experiments in which chronically stressed rats lost their elastic rat cunning and instead fell back on familiar routines and rote responses, like compulsively pressing a bar for food pellets they had no intention of eating. Moreover, the rats’ behavioral perturbations were reflected by a pair of complementary changes in their underlying neural circuitry. On the one hand, regions of the brain associated with executive decision-making and goal-directed behaviors had shriveled, while, conversely, brain sectors linked to habit formation had bloomed. Copyright 2009 The New York Times Company

Keyword: Stress
Link ID: 13173 - Posted: 06.24.2010

By Susan Milius Researchers convened August 12-15 at the American Ornithologists’ Union 2009 meeting in Philadelphia, Pa. They presented their latest findings on the evolution of female songs, the unexpected vocal anatomy of sage grouse and the perils of traffic noise for forest birds. —TO SING OR NOT TO SING It's not her latitude. It's her lifestyle. A new study may help explain why birdsong is more of a guy thing in temperate regions but plenty of females join the chorus in the tropics. Jordan Price of St. Mary’s College of Maryland in St. Mary’s City and his colleagues used New World blackbirds to study the evolution of female song. The group includes both tropical and temperate species, some with female singers and some without. Looking at the pattern of female singing on a family tree of 65 blackbird species, the researchers concluded that the original blackbirds founding the lineage had female singers. As the lineage diversified into modern species, the capacity for female song disappeared at least 11 times, Price reported August 15. Among blackbirds, then, the question isn’t why some females sing but why some don’t. Dividing the blackbird species into tropical and temperate dwellers yields only a rough correlation with the occurrence of female song, Price said. Instead he found a tighter correlation by looking at lifestyle. © Society for Science & the Public 2000 - 2009

Keyword: Language; Animal Communication
Link ID: 13172 - Posted: 06.24.2010