Michael Hopkin It seems that the more macho a man is — at least according to his hormones — the more the sight of an attractive woman will affect his judgement. Researchers at the University of Leuven in Belgium asked men to play an ultimatum game, in which they split a certain amount of money between them. High-testosterone men drove the hardest bargain — unless they had previously viewed pictures of bikini-clad models, in which case they were more likely to accept a poorer deal. The sight of flesh had less effect on the bargaining tactics of low-testosterone men. The testosterone dose that interested the researchers was that encountered by their participants when developing in the womb. This can be measured by comparing the lengths of the index and ring fingers — a relatively long ring finger is a sign of a high-testosterone man. For these men, even handling a bra was enough to sap their resolve, report economists Bram Van den Bergh and Siegfried Dewitte, who publish their findings in the journal Proceedings of the Royal Society B1. Pictures of landscapes or elderly women, or handling a t-shirt, had no effect on the men's steely bartering power. ©2006 Nature Publishing Group

Keyword: Sexual Behavior
Link ID: 8797 - Posted: 06.24.2010

KINGSTON, Ont. – The reason people can approach animals in the wild more easily from a car than by foot may be due to an innate "life detector" tuned to the visual movements of an approaching predator's feet, says Queen's University psychologist Niko Troje. "We believe this visual filter is used to signal the presence of animals that are propelled by the motion of their feet and the force of gravity," suggests Dr. Troje, Canada Research Chair in Vision and Behavioural Sciences. Conducted with Dr. Cord Westhoff from the Ruhr-Universität Bochum in Germany, the study was funded by the Canada Foundation for Innovation and the German Volkswagen Foundation. It will be published on-line April 18 in the international journal Current Biology. The researchers suggest this low level locomotion detector is part of an evolutionary old system that helps animals detect quickly – even on the periphery of their visual field – whether a potential predator or prey is nearby. "Research on newly hatched chicks suggests that it works from very early on in an animal's development," says Dr. Troje. "It seems like their brains are 'hard wired' for this type of recognition." One impetus for starting this research several years ago was a question by his young daughter, who asked him why she could get so much closer to wild rabbits in their neighborhood while riding on her bicycle rather than on foot. "I didn't have an answer for her then. Now, I think I have one," he says.

Keyword: Vision; Aggression
Link ID: 8796 - Posted: 06.24.2010

Studies of the brain using the video game Duke Nukem have shown how sleep affects long-term memory. The Belgian team used MRI scans to see how volunteers stored spatial information from the game. Sleep-deprived gamers recalled information from a different part of the brain to those who slept. Writing in Proceedings of the National Academy of Sciences (PNAS), the team said its work also shed light on how we navigate in the real world. "If you move to a new town, you have to think about where you are going," said Pierre Orban of Liege University in Belgium, one of the authors on the paper. But with time, once you know the city, you don't have to think about your route anymore." This automatic behaviour may be enhanced by sleep, the researchers believe. It mimics patterns of memory formation seen when a task is repeated. The work also explains how the brain is able to file and store this information. It has long been thought that sleep deprivation affects your ability to consolidate memories. To test the theory, the researchers gave the volunteers place-finding missions in a virtual city created in the Duke Nukem game. After an initial period of training to get used to the virtual terrain, the gamers were asked to find landmarks around the city while the scientists mapped their brain activity with MRI. (C)BBC

Keyword: Sleep; Learning & Memory
Link ID: 8795 - Posted: 04.18.2006

By ANNIE LUBLINER LEHMANN It would have been easy to ignore in other children, but when it comes to Jonah, our autistic son, nothing is beyond scrutiny. He was home on summer break from his residential school, and though his appetite was good and his behavior typical, watery droplets ran from his nose. There were no other cold symptoms, just a slow dribble that collected in the crease above his lips. The school nurse had called the week before to report that Jonah, who was almost 13 at the time, had taken a tumble, something he did more often than most. He was a slip-and-fall kind of guy, seeing only what he wanted, never the things that were in his way. We'd had many rides to the emergency room and knew from experience that any scans or X-rays would require general anesthesia, heavy artillery for a routine test. Hoping to avoid a hospital ordeal, the nurse agreed to follow Jonah closely for the next hours and days. She phoned often, assuring me that Jonah was fine, "up to his old tricks." I believed her and besides, he'd be home in a few days. I would be able to judge for myself. Copyright 2006 The New York Times Company

Keyword: Autism
Link ID: 8794 - Posted: 04.18.2006

By NICHOLAS WADE Researchers have made progress in understanding how a variant gene linked to schizophrenia may exert its influence in the brain. The findings are tentative but, if confirmed, could yield deep insights into the biological basis of the disease. The gene, called neuregulin-1, was first implicated in schizophrenia in 2002 by DeCode Genetics, a Reykjavik company that looks for the genetic roots of common diseases in the Icelandic population. But how the variant form of the gene contributed to the disease was far from clear, in part because even the normal gene's function is far from understood. A team led by Amanda J. Law of the University of Oxford in England and Daniel R. Weinberger of the National Institutes of Health has now developed clues as to how the gene may go wrong. Neuregulin is one of about 10 genes so far linked to schizophrenia. It plays many different roles in the brain, some concerned with synapses, the interconnections between neurons, so derangements of its function are a plausible source of schizophrenia. It is a long road, however, from knowing a variant gene is linked with a disease to understanding the biology of how the disease is caused. Copyright 2006 The New York Times Company

Keyword: Schizophrenia; Genes & Behavior
Link ID: 8793 - Posted: 04.18.2006

By JANE E. BRODY Faith Sullivan of Minneapolis was having a really hard time getting a good night's sleep. For years, she had slept about seven hours a night. Then, in her late 50's, something changed. After going to bed at 10 or 11 p.m., she would wake up around 3 a.m., unable to fall back to sleep. No, neither depression nor hot flashes were disrupting her night's rest. It was caffeine. She never drank caffeinated coffee in the evening, but she often had it as a midafternoon pick-me-up. Though she found it hard to believe that coffee at 4 p.m. could disturb her sleep at 3 a.m., at the suggestion of a friend she tried cutting it out. The result was striking. Within a day, she was back to sleeping seven hours a night. While not every insomniac's problem is so easily solved, many if not most of the millions of Americans who now rely on sleeping pills could cure their insomnia simply by changing their living and sleeping habits. Caffeine is not just in coffee. It's in tea, colas and other soft drinks, some herbal teas, chocolate and some medications (Anacin and Excedrin, for example). There's even a little caffeine in decaffeinated coffee and tea. For people highly sensitive to caffeine, its stimulant effects can last as long as 20 hours. Even decaffeinated coffee in the evening can keep me awake. Copyright 2006 The New York Times Company

Keyword: Sleep
Link ID: 8792 - Posted: 04.18.2006

New York, New York ––A recent study directed by the Mount Sinai School of Medicine suggests a ketogenic- high caloric diet may prevent the progression of Amyotrophic Lateral Sclerosis (ALS). This study, which appears in the April 3, 2006 issue of BMC Neuroscience, is the first to draw a correlation between diet and neuronal cell death, the cause of ALS. ALS is an adult-onset neurodegenerative disorder in which spinal and cortical motor neurons die causing relentlessly progressive weakness and wasting of skeletal muscles through the body. "ALS is such a devastating disease for those individuals diagnosed with the disorder," said Giulio Maria Pasinetti, M.D., Ph.D., Professor of Psychiatry and Neuroscience, Director of the Neuroinflammation Research Center at The Mount Sinai School of Medicine and lead author of this study. "The findings assert the significance of certain high caloric dietary intake in the prevention of ALS. In view of any available therapeutic application for the disease, this new evidence might bring hope to those affected." The cause of neuronal death in ALS is uncertain but study researchers say mitochondrial dysfunction plays an important role. Ketones promote mitochondrial energy production and membrane stabilization. Mitochondiral membrane dysfunction, loss of oxidative stress control, generation of excessive free radicals, neurofilament accumulation, and excitotoxicity are all implicated in the onset of ALS.

Keyword: ALS-Lou Gehrig's Disease
Link ID: 8791 - Posted: 06.24.2010

The octopus arm is extremely flexible. Thanks to this flexibility--the arm is said to possess a virtually infinite number of "degrees of freedom"--the octopus is able to generate a vast repertoire of movements that is unmatched by the human arm. Nonetheless, despite the huge evolutionary gap and morphological differences between the octopus and vertebrates, the octopus arm acts much like a three-jointed vertebrate limb when the octopus performs precise point-to-point movements. Researchers have now illuminated how octopus arms are able to form joint-like structures, and how the movements of these joints are controlled. The new findings, which appear in the April 18th issue of Current Biology, are reported by Tamar Flash of the Weizmann Institute of Science, Binyamin Hochner and German Sumbre of Hebrew University, and Graziano Fiorito of the Stazione Zoologica di Napoli. The extreme motility of the octopus arm demands a highly complex motor control system. Past work from Dr. Hochner's group showed that when retrieving food to its mouth, the octopus actually shapes its arm into a quasi-articulated structure by forming three bends that act like skeletal joints. This puts an artificial constraint of sorts on the arm's movement and simplifies the otherwise complex control of movement that would be needed for the arm to fetch food from a distant point to the octopus's mouth. In the new work, the researchers sought to identify how the octopus manages to transform its extremely flexible arm into a structure that acts like a jointed appendage.

Keyword: Miscellaneous
Link ID: 8790 - Posted: 04.18.2006

Researchers supported by the National Institute on Alcohol Abuse and Alcoholism (NIAAA), part of the National Institutes of Health (NIH), have identified new genes that may contribute to excessive alcohol consumption. The new study, conducted with strains of animals that have either a high or low innate preference for alcohol, provides clues about the molecular mechanisms that underlie the tendency to drink heavily. A report of the findings appears in the April 18, 2006 issue of Proceedings of the National Academy of Sciences. “These findings provide a wealth of new insights into the molecular determinants of excessive drinking, which could lead to a better understanding of alcoholism,” notes NIAAA Director Ting-Kai Li, M.D. “They also underscore the value that animal models bring to the investigation of complex human disorders such as alcohol dependence.” Mice that have been selectively bred to have either a high or low preference for alcohol have been a mainstay of alcohol research for many years, allowing investigators to study diverse behavioral and physiological characteristics of alcohol dependence. In the current study, NIAAA grantee Susan E. Bergeson, Ph.D., of the University of Texas (UT) at Austin, and a multi-site team of scientists participating in NIAAA’s Integrative Neuroscience Initiative on Alcoholism (INIA) used microarray techniques to study gene expression in the brains of these animals. Microarrays are powerful tools that investigators use for comprehensive analyses of gene activity.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 8789 - Posted: 06.24.2010

By Tracy Staedter, Discovery News — A computerized typewriter that translates electrical impulses from brainwave signals into letters and words could be available in the next five years. In the short term, the technology will allow its developers, from the Fraunhofer Institute and the Charité Hospital in Berlin, Germany, to watch a thinking and behaving brain function in real time. But in the long term, such a brain-machine interface could replace the joystick in electronic gaming or serve as a communication tool for people unable to speak or sign. "We are dreaming of something like a baseball cap with electrodes in the cap that can measure the brainwaves," said one of the scientists behind the project, Klaus-Robert Mueller of the Fraunhofer Institute. "People could just put on the cap and have a wireless connection from these electrodes to a computer and they can play video games." That vision, said Mueller, will require advances in electrode technology that allow the tiny, metal sensors to pick up electric signals from brainwave activity without making contact with the skin. © 2006 Discovery Communications Inc.

Keyword: Robotics
Link ID: 8788 - Posted: 06.24.2010

By Victor Limjoco With swelling prison populations, researchers are trying to understand the biology behind aggressive behavior. National Institute of Mental Health scientist Andreas Meyer-Lindenberg is looking for clues to how genes wire our brains early in life. "One of the most fascinating things," Meyer-Lindenberg says, about this field of science called psychiatric genetics, "is how it is possible that genes [can] encode for molecules that affect something as complex as behavior, even psychiatric illness such as depression and social behavior." He's focusing on a specific gene that was previously linked to impulsive violence in certain populations of people. A study in 2002 found that subjects with a particular form of a gene had a significantly higher risk of violence, but only in certain populations. Genes can affect complex behaviors like aggression, because they direct the production of proteins - the building blocks of living systems. Certain types of proteins, called enzymes, break down chemicals in the brain, most notably, serotonin - a chemical messenger in the brain that helps brains cells communicate to each other. To isolate how a variation in this gene, called MAOAG, might affect the wiring of the brain, Meyer-Lindenberg took MRI brain scans of more than 100 healthy volunteers. Since this genetic variation is common in our population, some of the volunteers had this variation, and some didn't. © 2005 Discover Media LLC.

Keyword: Aggression; Genes & Behavior
Link ID: 8787 - Posted: 06.24.2010

By STEPHEN MIHM Most prisons are notorious for the quality of their cuisine (pretty poor) and the behavior of their residents (pretty violent). They are therefore ideal locations to test a novel hypothesis: that violent aggression is largely a product of poor nutrition. Toward that end, researchers are studying whether inmates become less violent when put on a diet rich in vitamins and in the fatty acids found in seafood. Could a salmon steak and a side of spinach really help curb violence, not just in prison but everywhere? In 2001, Dr. Joseph Hibbeln, a senior clinical investigator at the National Institutes of Health, published a study, provocatively titled "Seafood Consumption and Homicide Mortality," that found a correlation between a higher intake of omega-3 fatty acids (most often obtained from fish) and lower murder rates. Of course, seeing a correlation between fatty acids and nonviolence doesn't necessarily prove that fatty acids inhibit violence. Bernard Gesch, a senior research scientist at Oxford University, set out to show that better nutrition does, in fact, decrease violence. He enrolled 231 volunteers at a British prison in his study; one-half received a placebo, while the other half received fatty acids and other supplements. Over time, the antisocial behavior (as measured by assaults and other violations) of the inmates who had been given the supplements dropped by more than a third relative to their previous records. The control group showed little change. Gesch published his results in 2002 and plans to start a larger study later this year. Similar trials are already under way in Holland and Norway. Copyright 2006 The New York Times Company

Keyword: Aggression
Link ID: 8786 - Posted: 04.17.2006

Washington -- Neuroscientists at Harvard Medical School and its affiliate Mclean Hospital have shown that long-term exposure to stress hormone in mice directly results in the anxiety that often comes with depression. After years of circumstantial evidence linking stress and depression, this evidence may be the "smoking gun" of what, for some, causes some types of mood disorders. The research appears in the April issue of Behavioral Neuroscience, which is published by the American Psychological Association. The findings are important for understanding the causes and improving the treatment of depression. Scientists already knew that many people with depression have high levels of cortisol, a human stress hormone, but it wasn't clear whether that was a cause or effect. Now it appears likely that long-term exposure to cortisol actually contributes to the symptoms of depression. Paul Ardayfio, PhD candidate, and Kwang-Soo Kim, PhD, made their discovery by exposing mice to both short-term and long-term durations of stress hormone, which in rodents is corticosterone. In humans, usually ongoing, chronic stress, such as caring for a spouse with dementia, rather than acute stress, has been associated with depression. Using 58 mice, the researchers gave the hormone in drinking water so as not to confound the results with the stress of injection. Chronic doses were 17 to 18 days of exposure; acute doses were 24 hours of exposure.

Keyword: Stress; Emotions
Link ID: 8785 - Posted: 04.17.2006

Bruce Bower Scientists working in Ethiopia's Middle Awash valley have uncovered fossils of a 4.1-million-year-old human ancestor that bolster the controversial proposition that early members of our evolutionary family evolved one at a time on a single lineage rather than branching out into numerous species. A team led by anthropologist Tim D. White of the University of California, Berkeley unearthed 31 fossils of Australopithecus anamensis, the earliest known species of this ancient hominid genus. The finds, from at least eight individuals, consist primarily of teeth and jaws, but include foot and hand bones and much of an upper right-leg bone. Anatomical similarities indicate that Au. anamensis evolved directly from an earlier hominid, Ardipithecus ramidus (SN: 1/22/05, p. 51: Available to subscribers at http://www.sciencenews.org/articles/20050122/fob2.asp), between 4.4 million and 4.1 million years ago, the researchers assert in the April 13 Nature. By 3.6 million years ago, they add, Au. anamensis had evolved into Australopithecus afarensis, the species that includes the partial skeleton known as Lucy. "There may have been times when one early hominid species evolved into another one without branching off into multiple species," White says. His view contrasts with that of researchers who suspect that hominids branched into many species over the past 6 million to 7 million years (SN: 5/3/03, p. 275: Available to subscribers at http://www.sciencenews.org/articles/20030503/fob1.asp). Copyright ©2006 Science Service.

Keyword: Evolution
Link ID: 8784 - Posted: 06.24.2010

After an article on the topic elicited a strong response from readers, Scientific American Mind magazine conducted a nationwide Zogby Interactive poll that found that 50 percent of Americans believe sexual orientation is not a choice, while only 11 percent said it is a conscious choice. Thirty-four percent believe it's a combination of both. The idea that sexual preference is a hard-wired part of who we are is consistent with a growing body of scientific research that indicates a biological basis for sexual orientation, including studies of identical twins, studies of other species that don't have cultural influences, and the discovery of genes that can change the sexual behavior in flies. But, as psychiatrist Jack Drescher says, "the clinical question has gotten caught up in this whole political argument." At the heart of the controversy is Columbia University psychiatrist Robert Spitzer. In 1973, he helped to get homosexuality removed from psychiatry's official classification manual of mental illnesses, the Diagnostic and Statistical Manual of Mental Disorders. But 30 years later, in 2003, he interviewed 200 people who claimed to have changed from gay to straight, and published the study concluding that such change is possible. © ScienCentral, 2000-2006.

Keyword: Sexual Behavior
Link ID: 8783 - Posted: 06.24.2010

By Greg Miller SAN FRANCISCO--The summer Olympics only come around every four years, and for elite athletes vying for a spot on their national teams, failure to qualify can be crushing. Now, researchers have taken a look at how the brain deals with dashed Olympic dreams. Their findings hint at a possible explanation for why athletes who've suffered tough losses often have a hard time getting back on top of their game. It's a frustrating problem for both athletes and sports psychologists, says Hap Davis, a Canadian psychologist based in Calgary. "You can get people feeling good again, but they don't perform at the level they need to," he says. To get a peek inside his patients' heads, Davis teamed up with cognitive neuroscientists, including Mario Liotti at Simon Fraser University in Burnaby, Canada. The team used functional magnetic resonance imaging to examine the brains of 14 swimmers, 10 women and four men, who didn't make the 2004 Canadian Olympic team. Inside the scanner, the swimmers each watched a video clip of themselves swimming their failed qualification race and another clip featuring a different swimmer. Not surprisingly, the swimmers rated their own videos more wrenching to watch. And their brains showed signs of their emotional pain, with heightened activity in the parahippocampus and other emotion-related areas that have been implicated in depression. (None of the swimmers had a prior history of depression). © 2006 American Association for the Advancement of Science.

Keyword: Emotions
Link ID: 8782 - Posted: 06.24.2010

Johns Hopkins researchers have discovered a gene in fruit flies that helps certain specialized neurons respond more quickly to bright light. The study, published in the April 4 issue of Current Biology, also has implications for understanding sensory perception in mammals. In teasing apart the molecular interactions and physiology underlying light perception, the researchers studied a gene they dubbed “Lazaro” that is expressed 15 times higher in the fly eye than the rest of the fly head. They found that this gene is required for a second biochemical pathway that controls the activity of a protein called the TRP channel. TRP channels are found in fruit fly neurons responsible for sensing light. The fly TRP channel is the founding member of a family of related proteins in mammals that are essential for guiding certain nerves during development and for responding to stimuli including heat, taste and sound. By shining bright light onto and recording electrical changes in single nerve cells in the fly eye, researchers found that neurons carrying a mutation in this gene cannot respond as well to light as compared to neurons carrying normal copies of this gene. In fact, the mutant neurons turn off their response to light four times faster than normal neurons. Because Lazaro helps fly TRP channels work at their maximum, it is possible that a Lazaro-like gene in mammals might also play a role in how well mammalian TRP channels work.

Keyword: Vision
Link ID: 8781 - Posted: 06.24.2010

By NICHOLAS BAKALAR Women can unconsciously detect the smell of fear, new research suggests, and the smell improves their performance on mental tasks. Scientists collected sweat from seven volunteers — four men and three women — who watched horror movies while holding gauze pads in their armpits. Then, their sweat was collected while they watched videos with neutral emotional content. Sixty-eight women next performed a word-association task while smelling the pads. The task involved watching two words flash on a screen one after the other, and then stating whether the two words were related. ("Arms" and "legs" are related; "arms" and "wind" are not.) The subjects were divided into three groups: the first smelled the sweat pads of sweat collected during the frightening video; the second smelled pads collected during the neutral video; and the third, a control group, smelled pads with no sweat on them. Without sacrificing speed, the women smelling the fear pads were more accurate than those in the other two groups when processing meaningful related words. There was no difference in speed or accuracy between the three groups when the words were not related. Copyright 2006 The New York Times Company

Keyword: Chemical Senses (Smell & Taste); Emotions
Link ID: 8780 - Posted: 06.24.2010

By JOHN NOBLE WILFORD In following the fossil tracks of human evolution, scientists have for years searched for links between Australopithecus, the kin of the famous "Lucy" skeleton, and even earlier possible ancestors. Now, they think they have found some connections in Ethiopia. An international team of paleontologists is reporting the discovery of transitional species superimposed in sediments in the neighborhood of a single site. The findings appear today in the journal Nature. Tim D. White, a paleontologist at the University of California, Berkeley, who was a team leader, and his colleagues said the 4.1-million-year-old fossils were anatomically intermediate between the earlier species Ardipithecus ramidus and the later species Australopithecus afarensis, the Lucy family. The newfound bones and teeth are the earliest remains of the most primitive Australopithecus, known as anamensis. "This new discovery closes the gap between the fully blown australopithecines and earlier forms we call Ardipithecus," Dr. White said in a statement. "We now know where Australopithecus came from before four million years ago." Copyright 2006 The New York Times Company

Keyword: Evolution
Link ID: 8779 - Posted: 04.14.2006

By Michael Shermer Amyotrophic lateral sclerosis (ALS) is a neuromuscular disease that attacks motor neurons until muscle weakness, atrophy and paralysis lead inexorably to death. Victims of this monstrous malady could be forgiven for feeling unlucky. How, then, can we explain the attitude of the disease's namesake, baseball great Lou Gehrig? He told a sellout crowd at Yankee Stadium: "For the past two weeks you have been reading about the bad break I got. Today I consider myself the luckiest man on the face of this earth." The Iron Horse then recounted his many blessings and fortunes, a list twice punctuated with "I'm lucky" and "That's something." Clearly, luck is a state of mind. Is it more than that? To explore this question scientifically, experimental psychologist Richard Wiseman created a "luck lab" at the University of Hertfordshire in England. Wiseman began by testing whether those who believe they are lucky are actually more likely to win the lottery. He recruited 700 subjects who had intended to purchase lottery tickets to complete his luck questionnaire, which is a self-report scale that measures whether people consider themselves to be lucky or unlucky. Although lucky people were twice as confident as the unlucky ones that they would win the lottery, there was no difference in winnings. © 1996-2006 Scientific American, Inc.

Keyword: Emotions
Link ID: 8778 - Posted: 06.24.2010