By Rachel Zelkowitz Nine beers in one night could put even a seasoned drinker under the table. But the pen-tailed tree shrew in Malaysia consumes the equivalent of that in alcoholic nectar several nights a week, researchers have discovered, and six other species of animals there consume smaller amounts of alcohol as well. Unlike humans, the animals seem to suffer no ill effects from their habit. How they have evolved to tolerate alcohol could teach us something about the origins of human alcohol consumption and abuse, researchers say. The pen-tailed tree shrew (Ptilocercus lowii) is a small, ratlike animal that inhabits the jungles of Southeast Asia. It feeds on the nectar of an ever-flowering plant, the bertam palm, which is a primary food source for many other species as well, says Frank Wiens of the University of Bayreuth in Germany. Wiens was observing tree shrews feed in the Malaysian jungle when he noticed an oddly familiar odor: "The palms smelled like a brewery," he says. Wiens realized that some of the animals might be consuming huge amounts of alcohol, which prompted him and colleagues to spend more than 3 years in the field studying the ecology of the bertam palm. Yeast cells in the palm's flowers ferment its nectar, they discovered, which can contain up to 3.8% alcohol--among the highest concentrations ever found in natural foods. The researchers observed seven mammalian species feeding on the nectar. The pen-tailed tree shrews guzzled the stuff longer than they did any other food source, for an average of 138 minutes per night, in the process helping to pollinate the plants. © 2008 American Association for the Advancement of Science

Keyword: Drug Abuse; Evolution
Link ID: 11872 - Posted: 06.24.2010

Susan T. Fiske Most people think they're less biased than average. But just as we can't all be better than average, we can't all be less prejudiced than average. Although the message—and the success so far—of Barack Obama's presidential campaign suggests an America that is moving past traditional racial divisions and prejudices, it's probably safe to assume that all of us harbor more biases than we think. Science suggests that most of us don't even know the half of it. A 20-year eruption of research from the field of "social neuroscience" reveals exactly how automatically and unconsciously prejudice operates. As members of a society with egalitarian ideals, most Americans have good intentions. But new research suggests our brains and our impulses all too often betray us. That's the bad news. But here's the good news: More recent research shows that our prejudices are not inevitable; they are actually quite malleable, shaped by an ever-changing mix of cultural beliefs and social circumstances. While we may be hardwired to harbor prejudices against those who seem different or unfamiliar to us, it's possible to override our worst impulses and reduce these prejudices. Doing so requires more than just good intentions; it requires broad social efforts to challenge stereotypes and get people to work together across group lines. But a vital first step is learning about the biological and psychological roots of prejudice. Here's the first thing to understand: Modern prejudice is not your grandparents' prejudice.

Keyword: Emotions
Link ID: 11871 - Posted: 06.24.2010

Children carrying the first gene that has been clearly linked to obesity find it harder than others to tell when they are full, London-based researchers say. They studied over 3,000 children to see whether the FTO gene impacts on the ability to burn calories or appetite. The researchers found those with copies of the gene's risky variant were less likely to have their appetite "switched off" when they should be full. The study is published in the Journal of Clinical Endocrinology & Metabolism. FTO is the first common gene to be linked to obesity in Caucasian populations. The researchers, from University College London and the Institute of Psychiatry, King's College London, set out to learn more about the way the gene works. They tested whether children aged eight to 11 carrying the higher risk gene variation had an altered appetite through height, weight and waist circumference measurements, and a questionnaire which asked parents about their child's eating habits. They found that children with the higher risk version of the gene tended to overeat and to struggle to recognise when they were full. The effect of the gene on appetite was the same regardless of age, sex, socio-economic background and body mass index. (C)BBC

Keyword: Obesity; Genes & Behavior
Link ID: 11870 - Posted: 07.28.2008

A drug used to lower blood pressure could prevent or delay thousands of Alzheimer's cases, US research has suggested. People taking angiotensin receptor blockers were up to 40% less likely to develop dementia than those taking other blood pressure drugs. And patients already suffering from dementia were less likely to get worse. The number of people in the UK with dementia is expected to soar to 1.7 million over the next two decades. This could mean an enormous extra burden for families and the taxpayer, but the Boston University School of Medicine research, presented at a conference in Chicago, suggests there could be ways to prevent it. High blood pressure over long periods can lead to damaged blood vessels, and is known to increase the risk of not only strokes and heart disease, but dementia as well. Some types of dementia are directly related to the condition of the arteries supplying the brain, but blood pressure is also thought to play a role in Alzheimer's disease, which is linked to the appearance of protein deposits in brain tissue. However, the reasons for this are not clear. The research looked at records of approximately six million people treated for high blood pressure between 2001 and 2006. Those who took angiotensin receptor blockers (ARBs) were less likely, over that period, to be diagnosed with dementia compared with those on other blood pressure medication such as ACE inhibitors. (C)BBC

Keyword: Alzheimers
Link ID: 11869 - Posted: 07.28.2008

Michael Marshall Dementia is twice as common in low-income countries as previously thought, because the standard technique for diagnosing it is not suited to those countries. The finding comes from a study involving nearly 15,000 participants. Previous studies indicated that dementia rates are much lower in developing countries. A comprehensive review suggested that it was half as common, possibly even less. The new study shows much smaller differences. The 10/66 Dementia Research Group, led by Martin Prince from King's College London, UK, surveyed people over the age of 65 in seven low- and middle-income countries, including China, India and Mexico. They used their in-house diagnostic kit, the "10/66 algorithm", which they argue is more sensitive to cultural differences than the standard method used – as outlined in the latest Diagnostic and Statistical Manual of Mental Disorders (DSM). The 10/66 method gave dementia rates that were about double those from the manual. Prince told New Scientist that the DSM was designed for developed countries, where education standards are high. It struggles to pick up impairments among people with little education. © Copyright Reed Business Information Ltd.

Keyword: Alzheimers
Link ID: 11868 - Posted: 06.24.2010

By Richard Gray, Science Correspondent When it comes to memory it is clear that men and women are simply not on the same wavelength. While men may fail to match a woman's ability to remember the date of an anniversary, they are better at storing a seemingly endless cache of facts and figures. Scientists believe they have now uncovered the reason for this difference between the sexes – they make the memories in different ways. Researchers at the Institute of Psychiatry, King's College London, have found that males use different genes from females when making the new connections in the brain that are needed to create long-term memories. They believe this might explain why men are far better at remembering "tactical" memories, such as travel directions and trivia, while women form more "emotional" memories such as birthdays, wedding anniversaries and details about the world around them. Professor Peter Giese, who led the Medical Research Council- funded research , said they had identified two genes that seemed to be important for learning and making memories in males but not females. © Copyright of Telegraph Media Group Limited 2008

Keyword: Learning & Memory; Sexual Behavior
Link ID: 11866 - Posted: 06.24.2010

Justin Mullins Electronic canes for the blind are designed to detect nearby objects and provide a stereo audio signal that informs a person of the location of obstacles. But they do not distinguish between stationary and moving objects. A pair of spectacles fitted with a camera and accelerometers that detect movement can, however. They are connected to a computer that spots any obstacles in the field of view and works out which are moving. The specs provide audio signals to the wearer to let them know what's happening around them, and which objects are moving, so they can navigate without bumps. The system was dreamed up by electronics company Philips. Interfacing with the brain to control devices such as wheelchairs, robots and prosthetic devices has great potential. Monkeys have shown impressive ability to control robot limbs using brain implants, but must "rewire" their brains through training to do it. It would make things easier to use the signals naturally used for hand-eye coordination. But nobody has been able to figure out how the part of the brain responsible for hand-eye coordination, the primary motor cortex, does its job. Even recording the activity of this brain region has proved difficult. © Copyright Reed Business Information Ltd.

Keyword: Vision; Robotics
Link ID: 11865 - Posted: 06.24.2010

Phil Hogan Now where was I? Ah, yes. I'm reading a book. It's about memory but of course I've already lost my thread. Neurons are involved, I know that much - involved, that is, not just in remembering what you've just read, for example, but also in the amazing way things can go in one ear and out of the other. I must try harder. I'm on chapter five but I'm also on a plane heading for San Francisco, where I have an appointment to see a memory expert at the university. After that, I'm whizzing off to New York to watch the 2008 US Memory Championships, where I'm expecting to get some tips on how to remember all the names in a telephone directory. A trip down memory lane, then, an odyssey of self-improvement. My powers of recall are less than astonishing these days. For weeks, I've been racking my so-called brain, trying to put a name to the little town in southern Italy, on the cliff tops above Ischia and Capri. In 1983, my wife and I got off an island ferry there, stopped for a beer, then took a bus down the coast. It's a nice place. Odysseus (speaking of odysseys) stopped to listen to the Sirens there. Not Amalfi, not Positano. The other one. Full of Brits. You probably know it. I know it. But what is it called? Every now and then, I try to conjure it out of the remembered glare and bustle and sea and sky of that summer. I can see it but I'm damned if I can say it. I'm determined not to look it up. I keep thinking it's bound to come back but it hasn't. © Guardian News and Media Limited 2008

Keyword: Learning & Memory; Alzheimers
Link ID: 11864 - Posted: 06.24.2010

Pain is a simple enough concept to grasp. You stub your toe, shout, perhaps utter a few expletives, rub it better and it eventually fades. But neuroscientists are realising that pain is much more complex than anyone thought possible, comprising not just physical sensations, but emotional ones too. Pioneering studies are providing insights into why some people experience debilitating chronic pain long after an injury has healed, as well as why some are more prone to pain than others, and why certain people never recover from bereavement. “Pain is much more than mere sensation. The psychological component is at least as important as the physiological processes giving rise to it,” says Dr Jonathan Brooks, a scientist at the Centre for Functional Magnetic Resonance Imaging of the Brain, at Oxford University. His research centre scans the brains of people with chronic pain and compares them with those of healthy people. While most pain goes away as an injury gets better, sometimes it remains for months or even years, long outlasting its original purpose. Chronic physical pain is debilitating and can cause disability, depression and post-traumatic stress disorder. It is also very common. A group from the University of Washington reported in the journal Archives of Surgery earlier this year that 63 per cent of patients who had sustained serious trauma still had injury-related pain a year later. It was most common in the 35-44 age group and in women, and least common in those with a college education. Copyright 2008 Times Newspapers Ltd.

Keyword: Pain & Touch
Link ID: 11863 - Posted: 06.24.2010

In a note-worthy study of the human brain, scientists have discovered that a large expanse of a musician's brain "shuts off" while improvising music. Jazz and science would seem to make strange bedfellows, but both form the basis of Charles Limb's career. On the one hand, he's a faculty member at the Peabody Conservatory of Music at Johns Hopkins University in Baltimore, MD, and a life-long jazz musician. On the other, he's also a doctor and assistant professor in Johns Hopkins School of Medicine's Department of Otolaryngology-Head & Neck Surgery. "The thing I love about jazz is that in many ways it's so unscientific," says Limb. "You know, when you listen to jazz, what you realize is that these musicians, they really live by breaking the rules, by sort of rejecting excessive control over what they're going to do. … And I think for a scientist who sort of thrives on controlling variables and really having a clear sense of order in all things, the freedom that really characterizes jazz — it's an unusual mix." That mix came front and center when Limb decided he wanted to use science to study jazz. In particular, he was interested in the neurological basis of improvisation. "The mental state, the creative state that you're in when you're improvising is entirely different than when you're playing something that you've learned by memory," he says. "As a jazz musician for most of my life, I've always wondered what takes place inside my head when I'm actually improvising something." © ScienCentral, 2000-2008

Keyword: Hearing
Link ID: 11862 - Posted: 06.24.2010

By Tina Hesman Saey Timing is everything, especially when it comes to basic biological functions such as eating, sleeping and detoxifying. Scientists have known for ages that metabolism is tied to the body’s daily rhythms, but have not known how. Now, two groups of researchers report in the July 25 Cell the discovery of a molecule that links metabolism to the circadian clock. The missing link turns out to be a protein called sirtuin 1 or SIRT1, which is also a key regulator of aging. Uncovering the mechanism that links metabolism and circadian rhythms could lead to drugs to combat obesity, aging and jetlag and help shift workers reset their body clocks. Already, SIRT1 is the target of resveratrol, a molecule found in red wine and other foods and that mimics the health benefits of a nutritious, calorie-restricted diet. “It’s an interesting connection,” says Herman Wijnen, a circadian geneticist at the University of Virginia in Charlottesville who was not involved in the new studies. “It helps us understand one important aspect of how clocks and metabolism relate to each other.” Body rhythms are governed by molecular clocks that take about a day to complete a full cycle, hence the name circadian clock. The clocks are composed of proteins whose concentrations or levels of activity rise and fall like the tide. © Society for Science & the Public 2000 - 2008

Keyword: Biological Rhythms; Genes & Behavior
Link ID: 11861 - Posted: 06.24.2010

By David Malakoff Zip. Zilch. Nada. There's no real difference between the scores of U.S. boys and girls on common math tests, according to a massive new study. Educators hope the finding will finally dispel lingering perceptions that girls don't measure up to boys when it comes to crunching numbers. "This shows there's no issue of intellectual ability--and that's a message we still need to get out to some of our parents and teachers," says Henry "Hank" Kepner, president of the National Council of Teachers of Mathematics in Reston, Virginia. It won't be a new message. Nearly 20 years ago, a large-scale study led by psychologist Janet Hyde of the University of Wisconsin, Madison, found a "trivial" gap in math test scores between boys and girls in elementary and middle school. But it did suggest that boys were better at solving more complex problems by the time they got to high school. Now, even that small gap has disappeared, Hyde reports in tomorrow's issue of Science. Her team sifted through scores from standardized tests taken in 2005, 2006, and 2007 by nearly 7 million students in 10 states. Overall, the researchers found "no gender difference" in scores among children in grades two through 11. Among students with the highest test scores, the team did find that white boys outnumbered white girls by about two to one. Among Asians, however, that result was nearly reversed. Hyde says that suggests that cultural and social factors, not gender alone, influence how well students perform on tests. © 2008 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Intelligence
Link ID: 11860 - Posted: 06.24.2010

Matt Kaplan The splashes, barks and grunts of baleen whales carry much more meaning than biologists thought, according to the latest survey of the marine mammals. The scientists behind the study say that these noises could be the ideal characteristics for conservationists to monitor to understand the growing impact of noises made by humans on the underwater environment. The songs of baleen whales — which have characteristic mouth combs, which they use for filter feeding — have been studied extensively, as have the non-song communications of toothed whales. But non-song communication in baleen whales has received little attention. “Most people focus on the song,” says Rebecca Dunlop at the University of Queensland in Australia. “It is simply amazing how much we were missing by not paying attention to all of the other [sounds] that the animals actually make.” Although studies of humpback whales, Megaptera novaeangliae, in the 1980s had noted these sounds, Dunlop and her colleagues took things a step further by monitoring a population of humpbacks every year between 2002 and 2005 as they migrated from Australia’s Great Barrier Reef to the Antarctic. © 2008 Nature Publishing Group –

Keyword: Animal Communication; Language
Link ID: 11859 - Posted: 06.24.2010

From The Economist print edition A new school of economists is controversially turning to neuroscience to improve the dismal science FOR all the undoubted wit of their neuroscience-inspired concept album, “Heavy Mental”—songs include “Mind-Body Problem” and “All in a Nut”—The Amygdaloids are unlikely to loom large in the annals of rock and roll. Yet when the history of economics is finally written, Joseph LeDoux, the New York band’s singer-guitarist, may deserve at least a footnote. In 1996 Mr LeDoux, who by day is a professor of neuroscience at New York University, published a book, “The Emotional Brain: The Mysterious Underpinnings of Emotional Life”, that helped to inspire what is today one of the liveliest and most controversial areas of economic research: neuroeconomics. In the late 1990s a generation of academic economists had their eyes opened by Mr LeDoux’s and other accounts of how studies of the brain using recently developed techniques such as magnetic resonance imaging (MRI) showed that different bits of the old grey matter are associated with different sorts of emotional and decision-making activity. The amygdalas are an example. Neuroscientists have shown that these almond-shaped clusters of neurons deep inside the medial temporal lobes play a key role in the formation of emotional responses such as fear. © The Economist Newspaper Limited 2008.

Keyword: Emotions; Brain imaging
Link ID: 11858 - Posted: 06.24.2010

Simple, everyday movements require the coordination of dozens of muscles, guided by the activity of hundreds of motor neurons. Now, researchers have revealed an important step in the process that guides the early development of neurons themselves, as they establish the precise connections between the spinal cord and muscles. This knowledge will help scientists search for drugs to treat diseases that destroy motor neurons, such as amyotrophic lateral sclerosis, or Lou Gehrig's disease. As a vertebrate organism develops, the long, outstretched processes of motor neurons wend their way from the spinal column to wire up every muscle in the body. In mammals, many hundreds of different types of motor neurons are needed to control the variety of muscle types used to coordinate movement. The highly specialized motor neurons that innervate muscles in the arms, legs, hands, and feet are the most recent of these to evolve. As an animal develops, these neurons become increasingly specialized - first establishing themselves as motor neurons, then taking on the characteristics needed to control a limb, then preparing to target a specific muscle. Proper function depends on each of these neurons finding its way from the spinal cord to the group of muscle cells that it is equipped to control. Now, Howard Hughes Medical Institute investigator Thomas M. Jessell, working together with Jeremy Dasen of New York University and Philip Tucker of The University of Texas at Austin, has discovered the genetic recipe for making these specialized motor neurons. The key ingredient is a gene called Foxp1, which regulates the activity of a series of crucial patterning genes of the Hox family, and thereby coordinates the identity and connectivity of motor neurons. Without FoxP1, the axons of motor neurons that extend into an animal's limb wander aimlessly and connect to muscles at random, Jessell and Dasen have found. The paper describing these findings is published in the July 25, 2008, issue of the journal Cell. © 2008 Howard Hughes Medical Institute.

Keyword: Development of the Brain
Link ID: 11857 - Posted: 06.24.2010

Alzheimer's may not affect knowledge as early as previously thought People with dementia may remember more than it first appears, according to researchers in Dundee and Fife. They believe knowledge may not be destroyed in conditions such as Alzheimer's disease until later than previously thought. The academics concluded that often patients would be able to recall facts, but became confused by the way the questions were asked. The research was carried out by Dundee, Abertay and St Andrews universities. The researchers asked patients to define simple words, such as "monkey", "salmon" or "tractor". Professor Trevor Harley, from Dundee University, explained: "People with dementia are notoriously bad at this sort of task: at first sight it looks like they've lost most of the detailed knowledge of the word. For example, the only thing they appear to know about a monkey might just be that it's an animal. "The assumption has been that Alzheimer's disease causes this knowledge to be destroyed. However, we found that if you probe the patient in the right way with appropriate questions that support them to search their stored knowledge, they can often generate more detailed information. That is, the knowledge isn't always lost at all. Of course eventually the information might be completely lost, but this might happen much later than people have previously thought." Clive Evers from the Alzheimer's Society welcomed the findings. He said: "As dementia progresses communication often becomes more difficult but this does not necessarily mean that a person's understanding has diminished. (C)BBC

Keyword: Alzheimers; Learning & Memory
Link ID: 11856 - Posted: 07.24.2008

By Anna-Marie Lever Female bottlenose dolphins whistle 10 times more often than usual after giving birth in order to help newborns recognise who is "mum". The findings by a US team appear in the journal Marine Mammal Science. These "signature whistles" are unique to each animal, allowing them to be used for identification. Bottlenose dolphins are highly social; in their first weeks, calves encounter many adult females that they could potentially mistake for their mothers. "The most obvious explanation for the increase in maternal signature whistle production is the need for the mother to be in contact with her calf," zoologist Dr Deborah Fripp from Dallas Zoo suggested. "However, the decrease in signature whistle production of [dolphin] mother Lotty after three weeks does not fit this idea, especially as calves actually wander further from their mothers as they get older." Instead, Dr Fripp said a likely purpose of this whistling enables a process called imprinting, whereby the calf learns to recognise its mother. "Bottlenose dolphins can swim at birth and are highly social. In other species, these traits are associated with imprinting. A calf can easily get separated from its mother and find itself among many other dolphins." BBC © MMVIII

Keyword: Animal Communication; Language
Link ID: 11855 - Posted: 06.24.2010

By Roger Dobson Men have long been accused of judging women on looks alone, but even the plainest Jane can get their hormones raging, a study has found. Research involving a group of male students found that their levels of the hormone testosterone increased to the same extent whether they were talking to a young woman they found attractive – or to one they didn't fancy much at all. After 300 seconds alone in the same room as a woman they had never met before, and in some cases did not find particularly attractive, the men's testosterone levels of the hormone had shot up by an average of around eight per cent. The study's authors believe the rise in testosterone may be an automatic and unconscious reaction that has evolved in man when faced with a woman, to prepare him for possible mating opportunities. The rising levels may then fuel more visible changes in male behaviour that occur in the presence of a woman, including a squaring of shoulders, an upright posture, and greater use of hands - and even, it is suggested, a flaring of the nostrils. The rise in the male hormone may also be the reason why men are more likely to tell women exaggerated stories about their job, career, education and earnings, the researchers believe. The study, published in the journal Hormones and Behaviour, involved 63 male students aged 21 to 25 who were not aware of the purpose of the study. © Copyright of Telegraph Media Group Limited 2008

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 11854 - Posted: 06.24.2010

By On Amir The human mind is a remarkable device. Nevertheless, it is not without limits. Recently, a growing body of research has focused on a particular mental limitation, which has to do with our ability to use a mental trait known as executive function. When you focus on a specific task for an extended period of time or choose to eat a salad instead of a piece of cake, you are flexing your executive function muscles. Both thought processes require conscious effort-you have to resist the temptation to let your mind wander or to indulge in the sweet dessert. It turns out, however, that use of executive function—a talent we all rely on throughout the day—draws upon a single resource of limited capacity in the brain. When this resource is exhausted by one activity, our mental capacity may be severely hindered in another, seemingly unrelated activity. Imagine, for a moment, that you are facing a very difficult decision about which of two job offers to accept. One position offers good pay and job security, but is pretty mundane, whereas the other job is really interesting and offers reasonable pay, but has questionable job security. Clearly you can go about resolving this dilemma in many ways. Few people, however, would say that your decision should be affected or influenced by whether or not you resisted the urge to eat cookies prior to contemplating the job offers. A decade of psychology research suggests otherwise. Unrelated activities that tax the executive function have important lingering effects, and may disrupt your ability to make such an important decision. In other words, you might choose the wrong job because you didn't eat a cookie. © 1996-2008 Scientific American Inc. All Rights Reserved.

Keyword: Attention
Link ID: 11853 - Posted: 06.24.2010

By Rachel Zelkowitz Who needs a GPS when you have, well, whatever migratory birds and sea turtles have? For centuries, humans have marveled at the ability of these and other animals to navigate the globe, in some cases returning to the same breeding spot year after year from as far as 15,000 kilometers away. How they find their way remains a mystery, but new research suggests their prowess may depend on the ability to "see" Earth's magnetic field. Researchers agree that however animals navigate, they use Earth's magnetic field as a guide. Theories about how animals detect these fields, a property called magnetosensitivity, generally fall into two camps. One group argues that tiny crystals of a magnetic mineral known as magnetite, which is found in the brains of some birds and in bacteria, are key. Other scientists say that animals carry photoreceptor molecules that enable them to actually "see" magnetic fields. How these molecules work is not clear, but some researchers think light might destabilize electrons in the photoreceptors, making them susceptible to Earth's magnetic pull. Previous work has shown that animals must be able to respond to blue light to detect magnetic fields, so researchers have eyed cryptochrome, a protein that allows plants and animals to sense blue light, as a likely candidate for the magnetosensitivity photoreceptor. But it's hard to isolate the effects of a single protein in a complex organism. So a team of researchers from the University of Massachusetts Medical School in Worcester swapped small, forgoing migratory birds and other large animals for the humble fruit fly. © 2008 American Association for the Advancement of Science.

Keyword: Animal Migration; Vision
Link ID: 11852 - Posted: 06.24.2010