By Bryan Smith The words on the pink post-it note, thumbtacked to a wall in his home, can't be any clearer: "This house, in Oak Park, Illinois, is where Bob and Donna live." But Bob Berry shakes his head. No. I live in Wichita Falls... don't I? Why, I have an exam tomorrow at my high school. I've talked to my father about it... or have I? Bob wonders. Lately, he can't be sure of anything. Except the nice woman. The one who always seems to be around, the one with the kind face who now takes his hand. Something about her seems familiar. But what? "No Bob, you already finished school. Don't you remember?" the woman says. "Did I?" "Yes. You were a professor at one of the best colleges in the country — Northwestern University — a Ph.D., a neuroanatomist." "But my father..." The woman, Donna Kersey, squeezes his hand. "Your father died, Bob, remember?" He stares at her blankly. "He did? I just talked to him." She hates having to tell him — again — but what can she do? Ever since a near-fatal cardiac arrest robbed Bob's brain of precious oxygen for close to 5 minutes, his memory has been like a blackboard swiped clean every few moments — erased. Pieces of information — the time, what day it is, where he lives — dissolve like vapor trails.

Keyword: Learning & Memory
Link ID: 12102 - Posted: 06.24.2010

By ROBIN MARANTZ HENIG The public-health crusade of the moment is a no-holds-barred war on obesity. Those waging it don’t have time for subtlety. When Senator Christopher Dodd introduced the Obesity Prevention Act of 2008 this summer, he called obesity “a medical emergency of hurricanelike proportions” that is wreaking havoc “on our families, on our society and on our health care system.” But some activists and academics, part of a growing social movement known as fat acceptance, suggest that we rethink this war — as well as our definition of health itself. Fat-acceptance activists insist you can’t assume someone is unhealthy just because he’s fat, any more than you can assume someone is healthy just because he’s slim. (They deliberately use the word “fat” as a way to reclaim it, much the way some gay rights activists use the word “queer.”) Rather, they say, we should focus on health measurements that are more meaningful than numbers on a scale. This viewpoint received a boost in August when The Archives of Internal Medicine reported that fully half of overweight adults and one-third of the obese had normal blood pressure, cholesterol, triglycerides and blood sugar — indicating a normal risk for heart disease and diabetes, conditions supposedly caused by being fat. This is a core argument of fat acceptance: that it’s possible to be healthy no matter how fat you are and that weight loss as a goal is futile, unnecessary and counterproductive — and that fatness is nobody’s business but your own. Copyright 2008 The New York Times Company

Keyword: Obesity
Link ID: 12101 - Posted: 06.24.2010

Why do we find it funny when some­one falls down? —William B. Keith, Houston William F. Fry, a psychiatrist and laughter researcher at Stanford University, explains: Every human develops a sense of humor, and everyone’s taste is slightly different. But certain fundamental aspects of humor help explain why a misstep may elicit laughter. The first requirement is the “play frame,” which puts a real-life event in a nonserious context and allows for an atypical psychological reaction. Play frames explain why most people will not find it comical if someone falls from a 10-story building and dies: in this instance, the falling person’s distress hinders the establishment of the nonserious context. But if a woman casually walking down the street trips and flails hopelessly as she stumbles to the ground, the play frame may be established, and an observer may find the event amusing. Another crucial characteristic is incongruity, which can be seen in the improbable or inconsistent relation between the “punch line” and the “body” of a joke or experience. Falls are incongruent in the normal course of life in that they are unexpected. So despite our innate empathetic reaction—you poor fellow!—our incongruity instinct may be more powerful. Provided that the fall event establishes a play frame, mirth will likely ensue. © 1996-2008 Scientific American Inc.

Keyword: Miscellaneous
Link ID: 12100 - Posted: 06.24.2010

Devin Powell As you read this sentence, your mind hones in on each word and blots out the rest of the page. This roving spot of attention tames the flood of visual information that hundreds of thousand of nerves attached to the back of your eye's retina stream into the brain. So far, most scientists held that the brain's outermost layer and main site of consciousness, the cortex, is responsible for housing the attention steering mechanisms that sort out all this sensory input. But back in 1984, the co-discoverer of DNA Francis Crick suggested that a simpler structure called the thalamus may also play a part in this process. Once thought to be only a highway that connects the eyes to the cortex, it could contain a mental searchlight that filters what we pay attention to, Crick proposed. To test this theory, Kerry McAlonan and colleagues at the National Eye Institute in Bethesda, Maryland, trained three macaque monkeys to pay attention to rectangular spots of light, each about the size of a thumb held up at arm's length. Unconscious control Their results show a quick surge of activity in the part of the thalamus that relays information to the cortex and, a split second later, a drop in activity in the thalamic reticular nucleus (TRN), a satellite structure known to turn off this superhighway of sensory information during sleep. © Copyright Reed Business Information Ltd

Keyword: Vision; Sleep
Link ID: 12099 - Posted: 06.24.2010

Colin Barras A microscope small enough to be mounted to the head of a freely moving mouse makes it possible to watch brain cell activity and whole animal behaviour simultaneously in mice. The device offers researchers a new way to study of human diseases using transgenic mice. Since researchers created the first transgenic mice in the 1980s, the mouse has become the lab animal of choice for medical research. There are now mouse "models" for a wide range of human genetic disorders, from Parkinson's to asthma. But correlating the activity inside cells with the behaviour of an animal as a whole is still a challenge, says Mark Schnitzer at Stanford University. Cell spotter "A lot of work has been done using brain slices, or anaesthetised animals – even using animals that are awake but restrained," he says. But so far it has been impossible to image cellular-level activity in a freely moving mouse. Schnitzer's team has now made it possible. They designed a tiny microscope weighing just 1.1 grams that can be worn by a mouse without significantly impairing its movement. The device has already been used to study the circulation of blood through the one-cell-wide capillaries in the brain of active mice. © Copyright Reed Business Information Ltd.

Keyword: Brain imaging
Link ID: 12098 - Posted: 06.24.2010

The discovery of another way in which the body appears to control how much it eats could shed fresh light on obesity. US researchers said poor diets may trigger a signalling system which prompts the body to consume even more. When the signals - involving a protein linked to inflammation - were blocked in mice, they maintained normal weight. A UK expert warned that the finding, in the journal Cell, may not lead to an effective anti-obesity drug because it could interfere with the immune system. The complexity of the controls governing the human metabolism, appetite and the laying down of fat has become clear over recent years. Despite some promising experiments in animals, none has yet produced a breakthrough in the battle against obesity. The latest "pathway" under investigation, by scientists at the University of Wisconsin-Madison, is normally associated with the immune system, and inflammation, one of the body's defence systems. The link to obesity was made when scientists investigated "metabolic inflammation", a chronic, low-level condition often seen in obesity-related diseases. In mice, a protein connected to inflammatory reactions appeared to be switched on when the animals were given a high fat, high sugar diet. Not only this, but once the protein was switched on, the mice started eating more, suggesting that it was part of a pathway involving the regulation of food intake. Closer examination of the a part of the brain called the hypothalamus, which is known to be involved in energy regulation, revealed the protein present there too. In mice genetically altered to block the pathway, even with a high fat diet available, they were able to maintain a healthy weight. (C)BBC

Keyword: Obesity
Link ID: 12097 - Posted: 10.04.2008

By Greg Miller With the meltdown of the global economy, many people think that their financial future is beyond their control. In such uncertain times, it's probably a good idea to take a deep breath before making any big decisions, because, according to a new study, the mind can play tricks on people when they think they've lost control of a situation. When life gets chaotic, it's natural to try to figure out what's going on. But sometimes, the desire for an explanation may lead us to perceive patterns that don't exist, says Jennifer Whitson, a management scholar at the University of Texas, Austin. A study conducted in the 1970s, for example, found a correlation between bad stock market performance and an increase in the amount of space newspapers devoted to horoscopes and articles about astrology. Failing to find an explanation for their falling fortunes in the economic data, people apparently started looking to the stars. Another study found that parachute jumpers are more likely to see a nonexistent figure in a picture of random dots and squiggles just before they jump. Intrigued by such findings, Whitson teamed up with Adam Galinsky, a social psychologist at Northwestern University in Evanston, Illinois. In one experiment, the researchers asked 41 undergraduates to recall a situation in which they'd lacked control (such as being a passenger in a car accident) and another group to recall a situation in which they'd had full control (such as going into an exam well-prepared). Then the subjects read passages describing an event preceded by an action that may or may not have influenced the event. One passage asked them to imagine that they were successful marketers whose ideas were rejected after they failed to perform their customary ritual of stomping the ground three times before the meeting. The subjects who previously recalled an in-control experience were more likely to write this off as mere coincidence than were those who'd recalled being out of control, Whitson and Galinsky report in tomorrow's issue of Science. © 2008 American Association for the Advancement of Science.

Keyword: Attention
Link ID: 12096 - Posted: 06.24.2010

Matt Kaplan Great artists are said to pour all their energies onto the canvas, leaving them exhausted after a flurry of creativity. Now, researchers have found that female birds make a similar sacrifice when colouring their eggs, creating vivid hues at the expense of their health. The blue in many birds' eggs comes from the compound biliverdin, a breakdown product of the heme unit in haemoglobin, which circulates freely in the blood. But biliverdin is not just a pigment, it is also an antioxidant used by the body to prevent cellular damage. Previous research has proven that when females lay vibrant blue eggs, their partners are more likely to stick around and help rear the young1. So researchers speculated that because the blue comes from an antioxidant, it is a signal to males of the female's health status. Some scientists have argued that the female is making a dangerous trade-off, giving up resources needed to sustain her health to convince her partner that her offspring are worth looking after. Determined to find out whether females were in fact sacrificing their health to lay blue eggs, Judith Morales at the University of Vigo in Spain and her colleagues monitored 100 boxes near the village of Lozoya in central Spain, where pied flycatchers (Ficedula hypoleuca) commonly nest. The team tracked the progress of 48 females from when they started nesting. © 2008 Nature Publishing Group

Keyword: Sexual Behavior; Evolution
Link ID: 12095 - Posted: 06.24.2010

By Bruce Bower A gene variant involved in brain development may contribute to reading problems, including dyslexia. Unlike speaking, reading is a thoroughly unnatural act. That doesn’t mean that biology has no role in literacy. A gene involved in early brain development influences a range of reading problems, including dyslexia, a new study published online October 1 in the American Journal of Psychiatry suggests. British children ages 7 to 9 who inherited a particular genetic sequence on chromosome 6 tended to perform poorly on tests of reading and spelling abilities, whether or not they had already been classified as dyslexic, say geneticist Silvia Paracchini of the University of Oxford in England and her colleagues. On average, carriers of the key genetic sequence scored as well on IQ tests as other kids did. In an earlier report, the scientists found that the DNA sequence spans part of a gene called KIAA0319 and is linked to dyslexia in children in England and the United States. Paracchini’s group has also shown that the chromosome 6 sequence often accompanies a reduced ability of the KIAA0319 gene to direct the prenatal migration of brain cells to appropriate destinations. Decreased protein production by KIAA0319 prompts subtle brain changes, beginning before birth, that contribute to reading problems, including dyslexia, the researchers propose. © Society for Science & the Public 2000 - 2008

Keyword: Dyslexia; Genes & Behavior
Link ID: 12094 - Posted: 06.24.2010

Ewen Callaway Lonely men ought to flaunt their copies of New Scientist. Women looking for both one-night stands and long-term relationships go for geniuses over dumb jocks, according to a new study of hundreds of university students. "Women want the best of both worlds. Not only a physically attractive man, but somebody in the long term who can provide for them," says Mark Prokosch, an evolutionary psychologist at Elon University in North Carolina, who led the study. To many women, a smart man will appeal because he is likely to be clever enough to keep his family afloat. But he may also pass on "good" genes to his children, say Prokosch and his colleagues at the University of California, Davis. Rather than ask women to rate qualities they seek in men, as other studies had done, Prokosch's team asked 15 college men to perform a series of tasks on camera. The volunteers read news reports, explained why they would be a good date, and what would be the ramifications of the discovery of life on Mars. They also threw and caught a Frisbee to parade their physical appeal. Each potential suitor also took a quantitative test of verbal intelligence. More than 200 women watched a series of these videos before rating each man's intelligence, attractiveness, creativity and appeal for a short-term or long-term relationship. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Intelligence
Link ID: 12093 - Posted: 06.24.2010

By JAMIE STENGLE -- Heart patients should be regularly screened for signs of depression, the American Heart Association recommended Monday. Depression is about three times more common in heart attack survivors and those hospitalized with heart problems than the general population, according to the recommendations published in the journal Circulation. The authors said only about half of heart doctors say they treat depression in their patients _ and not all those diagnosed with depression are treated. "I think we could reduce considerable suffering and improve outcomes," by screening, said Erika Froelicher, professor of nursing at the University of California, San Francisco. "I know we can do more." While there's no direct evidence that heart patients who are screened fare better, depression can result in poorer outcomes and a poorer quality of life, the panel said. Depressed patients may skip their medications, not change their diet or exercise or take part in rehabilitation programs, they said. Anyone from cardiologists to nurses to primary care doctors can and should be involved in determining whether a patient is depressed, said Froelicher, who was co-chair of the panel that wrote the recommendations. The panel suggests that heart patients be screened by first asking two standard questions: In the past two weeks, have you had little interest or pleasure in doing things? Have you felt down, depressed or hopeless? © Copyright 1996-2008 The Washington Post Company |

Keyword: Depression
Link ID: 12092 - Posted: 06.24.2010

Jennifer Viegas -- Human friends and relatives keep tabs on their loved ones by phone when they're apart, and now new research shows elephants do nearly the same thing with rumble vocalizations that can transmit over one and a half miles. The finding helps to explain how elephants almost always find their way back to their herd, even after they wander far off. Elephants can see and smell their fellow herd members over long distances too, but visual obstructions, such as rocks, trees and even other big animals, can block their views, while wind changes and smells can compromise odor detection. universe WATCH VIDEO: Elephants can recognize themselves in the mirror. "The auditory system seems to provide a method to detect and communicate with individuals over both long and short distances, and we know that individuals can use auditory information to determine the location and identity of herd members," lead author Katherine Leighty explained to Discovery News. Leighty, a behavioral ecologist at Disney's Animal Kingdom in Florida, and her team conducted the first systematic study of spontaneously produced elephant rumble vocalizations. These are typically infrasonic calls, with frequencies between 13 and 35 Hz, which fall outside the range of human hearing. © 2008 Discovery Communications, LLC

Keyword: Hearing; Animal Communication
Link ID: 12091 - Posted: 06.24.2010

By Zane B. Andrews and Tamas L. Horvath The obesity epidemic has led to increased scientific interest in how the brain controls human feeding behavior. Why do we get hungry? What biological mechanisms tell us what to eat and when to stop eating? It’s long been assumed that two neurobiological mechanisms largely govern food intake: one that controls the need to eat and one that controls the desire to eat. The hypothalamus in the brain regulates the homeostatic control of food intake by receiving, coordinating and responding to metabolic cues and signals from the digestive system. By integrating these metabolic signals, the hypothalamus tells us when we need to eat to maintain a body weight “set point,” much like a thermostat set on a specific temperature. It is clear, however, that higher brain centers that control the desire to eat also substantially influence our food consumption. The dopamine reward system is one such brain center. (When you covet a bowl of chocolate ice cream after dinner, a food that you don’t need to eat for hunger but want to eat, it is your dopamine reward system that gets excited.) In many situations, this desire to eat can override the need to eat, leading people to consume tasty foods even when they’re not hungry. Our inability to forego these rewarding aspects of food intake override long-term homeostatic control, contributing to obesity. Although the hypothalamus will direct intake based on the metabolic value of the food—when you’re very hungry, you seek out food with lots of calories—it remains to be determined whether the dopamine reward system can also sense a food’s energy content. In other words, does the dopamine system care about calories, or is it just concerned with taste and pleasure? © 1996-2008 Scientific American Inc

Keyword: Obesity; Drug Abuse
Link ID: 12090 - Posted: 06.24.2010

Andy Coghlan Out-of-control boys facing spells in detention or anti-social behaviour orders can now blame it all on their hormones. The "stress hormone" cortisol – or low levels of it – may be responsible for male aggressive antisocial behaviour, according to new research. The work suggests that the hormone may restrain aggression in stressful situations. Researchers found that levels of cortisol fell when delinquent boys played a stressful video game, the opposite of what was seen in control volunteers playing the same game. The results suggest that biology rather than peer pressure might play a larger role than previously thought in delinquent behaviour, and raise new possibilities for diagnosing and treating such disorders. Virtual rival The study pitted each volunteer against a pugnacious, virtually generated rival boy in a computer game that had them competing for a monetary reward. The game was deliberately rigged to subject volunteers to stress, frustration, provocation, and taunting from their adversary. Saliva samples from the 95 control volunteers showed that their cortisol levels rose by an average of 48%, as expected in stressful situations. But in the 70 participants with conduct disorder, levels of cortisol dropped by an average of 30%. © Copyright Reed Business Information Ltd

Keyword: Aggression; Hormones & Behavior
Link ID: 12089 - Posted: 06.24.2010

By Andrea Thompson Scientists may have found the glue that keeps fearful memories stuck in the brain, a discovery that could be useful in new treatments for Alzheimer's disease and post-traumatic stress disorder. That glue seems to be a protein that is key to maintaining the structure of cells and also is essential to embryonic development, a new study suggests. The protein, called beta-catenin, transmits early signals in species ranging from flies to frogs to mice that separate an embryo into front and back or top and bottom. It also acts like Velcro, fastening a cell's internal skeleton to proteins on its external membranes that in turn connect them to other cells. Story continues below ↓advertisement Previous studies have found other factors that govern our feelings of fear: * One study found a 'fear factor' gene that controls how neurons fire in the brain when mice are faced with impending danger. * Another found that the brain can learn to fear something, such as a bee's sting, when we view someone else's fear. * Another recent study detailed how primates and other mammals learned to fear and avoid snakes. © 2008 LiveScience.com.

Keyword: Learning & Memory; Emotions
Link ID: 12088 - Posted: 06.24.2010

Ewen Callaway Money can't buy love, but it seems to earn you more babies. Rich men sire more children than paupers, according to a new study of thousands of middle-aged British men. Women are more likely to marry men who can provide for them and their children than penniless men, says Daniel Nettle, a behavioural scientist at Newcastle University, UK, who led the new study. "It's not that if you're richer you'll have more children – if you're richer you're less likely to be childless," he says. For much of civilization, females have tended to mate with better providers, but many sociologists argue that the industrial and sexual revolutions have immunised people in developed countries such evolutionary pressures. Census surveys have suggested that wealthier men have fewer kids, says Rosemary Hopcroft, a sociologist at the University of North Carolina in Charlotte, who is not affiliated with the study. However, these surveys are problematic because they tend to look at household income and tally only a mother's children, she says. The children of divorced and remarried men tend to get left out. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Evolution
Link ID: 12087 - Posted: 06.24.2010

Genetic research could shed light on what is happening in people with the mysterious sleep disorder narcolepsy. The condition causes extreme daytime sleepiness, and sudden muscle weakness. Japanese researchers found a genetic variant linked to a much higher risk of narcolepsy, publishing their results in the journal Nature Genetics. It is linked to genes involved in regulating sleep, and the scientists say their finding could help unravel narcolepsy's causes. The condition is an uncommon and distressing one - people with it can suffer "sleep attacks" without any warning during any normal activity. In addition, some people can experience "cataplexy", where strong emotions such as anger, surprise, or laughter can trigger an instant loss of muscle strength, which, in some cases, can cause collapse. The causes are still not completely clear, although some scientists believe they revolve around a shortage of a chemical called hypocretin which sends signals to the brain about sleeping and waking up. There is strong evidence that the condition can run in families, so the University of Tokyo team are looking for the genetic differences which may be involved. They looked at the genetic code of hundreds of volunteers, some with narcolepsy, some without, to look for differences. The variant they found was linked to an 79% higher chance of narcolepsy in Japanese people, and a 40% increased chance in other ethnic groups. It is found close to two genes, CPT1B, and CHKB, which have already been singled out as candidates for involvement in the disorder - as they both have a role in regulating sleep. (C)BBC

Keyword: Narcolepsy; Genes & Behavior
Link ID: 12086 - Posted: 09.29.2008

by Jon Bardin If the key to our cognitive success is functional specificity, then synaptic complexity is the underlying cause. The history of pharmaceutical trials is littered with cases of drugs that show promise in mice but ultimately fail when tested in humans, often for reasons poorly understood by the scientists who study them. Such failures generally are explained in one of two ways: Either there is a problem with the underlying biological model itself, or there is a problem with the way the success of the model is being measured. Now a recent breakthrough by the Cambridge neuroscientist and geneticist Seth Grant may provide a third possibility. In a report published in the June 2008 issue of Nature Neuroscience, Grant and his colleagues analyzed synapses in organisms of increasing evolutionary complexity, from single-celled organisms to vertebrates. They found that more advanced organisms also had more complex synapses, allowing neurons to communicate in more complicated ways. This finding upends the classical model of intelligence, in which the number of neurons, not their complexity, predicts the capacity for greater intelligence and higher-order behaviors. Compounding this, many mouse models are based on incomplete behavioral measures because the true biology of the disease is unknown. Depression in mice, for example, is often measured by how fast a mouse swims. ©2005-2008 Seed Media Group, LLC.

Keyword: Evolution; Animal Rights
Link ID: 12085 - Posted: 06.24.2010

From The Economist print edition THE function of sleep, according to one school of thought, is to consolidate memory. Yet two Italians have no problems with their memory even though they never sleep. The woman and man, both in their 50s, are in the early stages of a neurodegenerative disease called multiple system atrophy. Their cases raise questions about the purpose of sleep. Healthy people rotate between three states of vigilance: wakefulness, rapid eye-movement (REM) sleep and non-REM sleep. But all three are mixed together in the Italian patients. The pair were initially diagnosed by Roberto Vetrugno of the University of Bologna and his colleagues as suffering from REM behavioural disorder, in which the paralysis, or cataplexy, that normally prevents sleeping people from acting out their dreams is lost. This can cause people in REM sleep to twitch and groan, sometimes flailing about and injuring their bedmates. These patients, however, soon progressed from this state to an even odder one, according to a report in Sleep Medicine. One of the principal ways to measure sleep is to monitor brainwave activity, which can be done by placing electrodes on the scalp in a technique known as electroencephalography (EEG). Non-REM sleep itself is divided into four stages defined purely by EEG patterns; the first two are collectively described as light sleep and the last two as deep or slow-wave sleep. When the Italian patients appeared to be asleep, their EEGs suggested that their brains were either simultaneously awake, in REM sleep and non-REM sleep, or switching rapidly between the three. Yet when subjected to a battery of neuropsychological tests, they showed no intellectual decline. © The Economist Newspaper Limited 2008.

Keyword: Sleep; Learning & Memory
Link ID: 12084 - Posted: 06.24.2010

People who have a stroke seem to recover faster when they use a mirror to create the illusion that their paralyzed limb is moving alongside a healthy one, a Japanese researcher said Friday. "The mental aspect of rehabilitation has far greater importance than previously understood and should be paid far more attention," Kazu Amimoto of Tokyo Metropolitan University said in a statement. Amimota presented his findings on the therapy at the World Stroke Conference in Vienna. A stroke is a brain injury caused by a lack of blood that deprives the brain of oxygen and glucose. People who have had a stroke often develop hemiplegia — paralysis of one side of the body. Traditionally, stroke patients take therapy to stimulate and exercise the paralyzed half of their body. In the mirror approach, a mirror is placed on the middle of the patient's body so that movements from the healthy limb appear to be mimicked by the paralyzed arms and legs. The optical illusion seems to stimulate the brain and improve motor function in paralyzed areas, Amimoto said. © CBC 2008

Keyword: Stroke
Link ID: 12083 - Posted: 06.24.2010