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by Sunny Bains A MONKEY sits on a bench, wires running from its head and wrist into a small box of electronics. At first the wrist lies limp, but within 10 minutes the monkey begins to flex its muscles and move its hand from side to side. The movements are clumsy, but they are enough to justify a rewarding slug of juice. After all, it shouldn't be able to move its wrist at all. A nerve connection in the monkey's upper arm had previously been blocked with an anaesthetic that prevented signals travelling from its brain to its wrist, leaving the muscles temporarily paralysed. The monkey was only able to move its arm because the wires and the black box bypassed the broken link. The monkey was in Eberhard Fetz's lab at the University of Washington in Seattle. The experiment, performed last year, was the first demonstration of a new treatment that might one day cure paralysis, which is typically caused by a broken connection in the spinal cord. Though much work has focused on using stem cells to regrow damaged nerve fibres, some researchers believe that an electronic bypass like this is equally viable. The idea is to implant electronic chips in the relevant regions of the brain to record neural activity. Then a decoder deciphers the neural chatter, often from thousands of neurons, to figure out what the brain wants the body to do. These messages must then be relayed - ideally wirelessly - to electrodes that deliver a pulse of electricity to stimulate the muscles into action. Such "brain chips" are already restoring hearing to the deaf and vision to the blind, and helping to stave off epileptic fits, so the idea isn't as far-fetched as it might sound (see "Bionic medicine"). © Copyright Reed Business Information Ltd.

Keyword: Robotics; Regeneration
Link ID: 13227 - Posted: 06.24.2010

The number of unexplained infant deaths - or cot deaths - has been falling, provisional figures from the Office of National Statistics suggest. There were 264 such deaths in 2007 across England and Wales, down 7% on the year before - which itself saw a significant fall in numbers. The rate was highest among babies born outside marriage where only the mother registered the birth. What causes the deaths is unclear, but there are measures to reduce the risk. These include putting a baby on its back to sleep, not smoking in the vicinity of the baby and not sharing a bed if the parent is very tired or has been drinking. The majority of deaths were among babies of a normal birthweight - 2,500 grammes or 5.5lbs and above, and occurred between 28 days and one year of age. At a rate of 1.42 per 1,000 live births, the rate among unmarried mothers registering the birth alone was eight times that of babies born within marriage. For births inside and outside marriage - and where the baby was registered by both parents - the death rate among parents in the routine and manual occupations was twice that among those classified as managerial or professional. Age was also a factor: rates were highest in mothers under 20, and fell the older she became. There were also regional variations: the North East had the highest rate, at 0.66 per 1,000 births, and the East of England the lowest, at 0.32 per 1,000. The figures include deaths described both as sudden infant deaths and those for which the cause is "unascertained" after a full investigation. ONS researchers said the terms were used interchangably by coroners. (C)BBC

Keyword: Sleep
Link ID: 13226 - Posted: 08.31.2009

Infants and preschoolers often appear to have a carefree life but a study suggests almost 15 per cent may have high levels of depression and anxiety. In the five-year study of 1,758 children born in Quebec and their mothers, 15 per cent of preschoolers suffered from atypically high levels of depression and anxiety, researchers reported in the Journal of Child Psychology and Psychiatry. Feelings of depression and anxiety are a normal part of a child's develoment that increase over the preschool years, the researchers said. It's abnormally high levels of depression and anxiety that are of concern. "We found that children with difficult temperaments and maternal depression were the most important risk factors. These risk factors can be helped by interventions," said study author Sylvana Côté, a professor at the University of Montreal's department of social and preventive medicine. The signs can be spotted as early as the first year of life, the researchers found. For the study, mothers were interviewed about whether the child was nervous, high strung or tense, fearful or anxious, worried, less happy than other children or had difficulty having fun. The questions are considered a reliable way of determining whether children are at risk for depression and anxiety. Infant temperament and a mother's history of depression were important predictors of atypically high depressive and anxiety problems during preschool years, the researchers found, after controlling for low education and maternal antisocial behaviour. © CBC 2009

Keyword: Depression; Development of the Brain
Link ID: 13225 - Posted: 06.24.2010

By MARIA CHENG, BARCELONA, Spain – An experimental drug reduces the stroke risk in patients with irregular heartbeats by nearly four times, compared with the popular drug warfarin — but possibly at a cost, according to new research released Sunday. Patients taking the new drug dabigatran etexilate, made by German pharmaceutical Boehringer Ingelheim, also were slightly more likely to have heart attacks or stomach pain, according to the research presented at the European Society of Cardiology meeting in Barcelona. Patients with irregular heartbeats are up to 17 times more likely to have a stroke than healthy people. About one-sixth of all strokes occur in patients with irregular heartbeats who also have other risk factors such as smoking or obesity. In the United States, there are about 2 million people with such a condition. Until now most such patients have been given warfarin, which has been around since the 1950s and has side effects including bleeding risks and requires lifestyle changes such as dietary restrictions. Doctors hope the new drug can help improve treatment for patients, who must be monitored continuously if they are put on warfarin and avoid alcohol and foods such as spinach and cranberries. © 2009 The Associated Press.

Keyword: Stroke
Link ID: 13224 - Posted: 06.24.2010

In a finding that sheds new light on the neural mechanisms involved in social behavior, neuroscientists at the California Institute of Technology (Caltech) have pinpointed the brain structure responsible for our sense of personal space. The discovery, described in the August 30 issue of the journal Nature Neuroscience, could offer insight into autism and other disorders where social distance is an issue. The structure, the amygdala—a pair of almond-shaped regions located in the medial temporal lobes—was previously known to process strong negative emotions, such as anger and fear, and is considered the seat of emotion in the brain. However, it had never been linked rigorously to real-life human social interaction. The scientists, led by Ralph Adolphs, Bren Professor of Psychology and Neuroscience and professor of biology and postdoctoral scholar Daniel P. Kennedy, were able to make this link with the help of a unique patient, a 42-year-old woman known as SM, who has extensive damage to the amygdala on both sides of her brain. "SM is unique, because she is one of only a handful of individuals in the world with such a clear bilateral lesion of the amygdala, which gives us an opportunity to study the role of the amygdala in humans," says Kennedy, the lead author of the new report. © 2002-2009 redOrbit.com.

Keyword: Emotions
Link ID: 13223 - Posted: 06.24.2010

by Ewen Callaway A man's spit may indicate what kind of father and husband he is. In polygamous societies, men with high levels of testosterone in their saliva are more likely to take several wives and give their children less attention, compared to those with less of the sex hormone coursing through their bodies. The new study of rural Senegalese villagers adds to previous work underscoring testosterone's critical role in a mating and parenting. High testosterone levels have been linked to increased sexual activity, infidelity and marital conflict. However, after men become fathers, their bodies typically pump out less of the hormone. "This is good for us, so we can adapt to social challenges very quickly," says Alexandra Alvergne, an anthropologist at the University of Montpellier, France, and the University of Sheffield, UK, who led the new study. To find out whether testosterone's connection to mating and parenting also applies in societies where men may have several wives, Alvergne measured testosterone levels in 21 polygynous fathers as well as 32 monogamous dads and 28 unmarried men without children, all living in Senegalese villages. She also asked the men's wives how much time and money their husband devoted to his family. © Copyright Reed Business Information Ltd

Keyword: Hormones & Behavior; Aggression
Link ID: 13222 - Posted: 06.24.2010

by Gaia Vince It's hard to ignore a face filled with disgust, but people with an unsightly skin disorder seem to have a muted response to such facial expressions. This reduced sensitivity may serve to protect them from hurtful reactions. Christopher Griffiths, a dermatologist at Manchester University, UK, and colleagues showed people with psoriasis – a non-infectious skin condition that produces reddening and lesions – a series of images of faces while scanning their brains. Images of disgusted faces elicited less activation in the insular cortex, which processes feelings and observations of disgust, compared with a control group. Images of fearful faces produced normal levels of activation in the amygdala, which responds to fear, in both groups. Volunteers with psoriasis were also less likely to identify disgust in faces that showed only subtle signs of the emotion, compared with controls. People often react with disgust to psoriasis, even thought it is not infectious, says Griffiths. He reckons the brain adaptations in people with the disease "emerged to protect people that do not conform to facial norms". The psychological burden of the disorder is always far worse than the physical pain, says Linda Papadopoulos, a psychodermatologist based in London who specialises in the social effects of skin disorders. © Copyright Reed Business Information Ltd.

Keyword: Emotions
Link ID: 13221 - Posted: 06.24.2010

By Jessica Bennett | Newsweek Web Exclusive Ricky Gervais's new film, The Invention of Lying, is about a world where lying doesn't exist, which means that everybody tells the truth, and everybody believes everything everybody else says. "I've always hated you," a man tells a work colleague. "He seems nice, if a bit fat," a woman says about her date. It's all truth, all the time, at whatever the cost. Until one day, when Mark, a down-on-his-luck loser played by Gervais, discovers a thing called "lying" and what it can get him. Within days, Mark is rich, famous, and courting the girl of his dreams. And because nobody knows what "lying" is, he goes on, happily living what has become a complete and utter farce. It's meant to be funny, but it's also a more serious commentary on us all. As Americans, we like to think we value the truth. Time and time again, public-opinion polls show that honesty is among the top five characteristics we want in a leader, friend, or lover; the world is full of woeful stories about the tragic consequences of betrayal. At the same time, deception is all around us. We are lied to by government officials and public figures to a disturbing degree; many of our social relationships are based on little white lies we tell each other. We deceive our children, only to be deceived by them in return. And the average person, says psychologist Robert Feldman, the author of a new book on lying, tells at least three lies in the first 10 minutes of a conversation. "There's always been a lot of lying," says Feldman, whose new book, The Liar in Your Life, came out this month. "But I do think we're seeing a kind of cultural shift where we're lying more, it's easier to lie, and in some ways it's almost more acceptable." As Paul Ekman, one of Feldman's longtime lying colleagues and the inspiration behind the Fox TV series "Lie To Me," defines it, a liar is a person who "intends to mislead," "deliberately," without being asked to do so by the target of the lie. Which doesn't mean that all lies are equally toxic: some are simply habitual—"My pleasure!"—while others might be altruistic. But each, Feldman argues, is harmful, because of the standard it creates. And the more lies we tell, even if they're little white lies, the more deceptive we and society become. © 2009 Newsweek, Inc

Keyword: Emotions
Link ID: 13220 - Posted: 06.24.2010

Matt Walker Male free-tailed bats sing intricate and complex "love songs" to woo prospective female mates, new research has found. A detailed analysis of the structure of the bats' song has found they use a defined syntax and order of syllables. That makes the bats' songs more similar to those produced by birds than by other mammals such as mice. Among mammals, only whales may produce more complex songs, scientists report in the journal PLoS One. In 2008, a team of researchers including Dr Kirsten Bohn of Texas A&M University in College Station, Texas, US discovered that Brazilian free-tailed bats (Tadarida brasiliensis) sang songs that appeared to contain defined phrases and syllables. "But we only had songs from a few individuals in a captive colony," says Dr Bohn. Now Bohn and her colleagues have examined over 400 songs produced by 33 individual free-tailed bats living in different colonies in two different regions. The researchers found that all the bats produce songs with a common hierarchical structure. BBC © MMIX

Keyword: Sexual Behavior; Animal Communication
Link ID: 13219 - Posted: 06.24.2010

By Hilmar Schmundt Imagine controlling machines, typing text or juggling balls using nothing but the power of thought. What sounds like far-fetched science fiction is gradually becoming possible, providing hope for disabled patients -- and new gimmicks for the computer gaming industry. My original plan was to write this article with nothing but the power of thought, but the technology of transforming ideas into characters is still crude and prone to error. The first word alone took a few minutes, and even after that the result was still "diz" instead of "this." Still, that little sentence is like a little miracle. The old dream of mind-reading is slowly becoming reality -- though this time around it is the product of machines rather than the minds of fiction writers. "The advances are tremendous," says Christoph Guger, the developer of a brain-reading system. "In the past, you would have had to train for days. Today, entering text takes only a few minutes." Guger is an engineer and a businessman. But with his hair falling past his jacket's collar, he looks the part of a start-up entrepreneur. Still, he is certainly not new to the business. His company, Guger Technologies, which is based in the Austrian city of Graz, has been a supplier to countless brain-research laboratories for years. In addition to scalpels and medications, though, Guger also sells thought-transport technology. © SPIEGEL ONLINE 2009

Keyword: Brain imaging
Link ID: 13218 - Posted: 06.24.2010

From The Economist print edition THAT the risk-taking end of the financial industry is dominated by men is unarguable. But does it discriminate against women merely because they are women? Well, it might. But a piece of research just published in the Proceedings of the National Academy of Sciences by Paola Sapienza of Northwestern University, near Chicago, suggests an alternative—that it is not a person’s sex, per se, that is the basis for discrimination, but the level of his or her testosterone. Besides being a sex hormone, testosterone also governs appetite for risk. Control for an individual’s testosterone levels and, at least in America, the perceived sexism vanishes. Dr Sapienza and her colleagues worked with aspiring bankers (MBA students from the University of Chicago). They measured the amount of testosterone in their subjects’ saliva. They also estimated the students’ exposure to the hormone before they were born by measuring the ratios of their index fingers to their ring fingers (a long ring finger indicates high testosterone exposure) and by measuring how accurately they could determine human emotions by observing only people’s eyes, which also correlates with prenatal exposure to testosterone. The students were then presented with 15 risky choices. In each they had to decide between a 50:50 chance of getting $200 or a gradually increasing sure payout, which ranged from $50 up to $120. (Some of this money was actually paid over at the end of the experiment, to make the consequences real.) The point at which a participant decided to switch from the gamble to the sure thing was reckoned a reasonable approximation of his appetite for risk. © The Economist Newspaper Limited 2009.

Keyword: Emotions; Sexual Behavior
Link ID: 13217 - Posted: 06.24.2010

By Bruce Bower Gut-wrenching fears of snakes and spiders may start early for many women. Before their first birthdays, girls but not boys adeptly learn to link the sight of these creatures to the frightened reactions of others, a new study suggests. Neither infant girls nor boys link happy faces with snakes and spiders, reports study author David Rakison of Carnegie Mellon University in Pittsburgh in an upcoming Evolution & Human Behavior. Youngsters of both sexes also don’t tend to associate images of flowers and mushrooms with either fearful or happy faces, he finds. In Rakison’s tests, 11-month-old babies first looked at pairs of images—a happy or fearful cartoon face was paired with a snake, spider, flower or mushroom. After the first brief display, Rakison timed how long each child gazed at new pairs of images. A youngster who learned to associate two images, say a fearful face with a snake, would gaze longer at a violation of what he or she expected to see, such as a happy face with a snake, the researcher reasoned. Only girls associated the snake or spider that they originally saw with a fearful reaction and then acted on that knowledge, looking longer at the unexpected appearance of a happy face with a new snake or spider, Rakison proposes. No other pair of images elicited longer gazes from girls or boys. © Society for Science & the Public 2000 - 2009

Keyword: Emotions; Sexual Behavior
Link ID: 13216 - Posted: 06.24.2010

By Greg Miller During an epileptic seizure, waves of abnormal electrical activity sweep through the brain. That can create some strange experiences, including hallucinations and feelings of déjà vu. Even stranger is the recently reported case of an epileptic woman who feels that she has become a man during some seizures. In a paper in press at Epilepsy & Behavior, Burkhard Kasper and colleagues at the University of Erlangen-Nürnberg in Germany report that the 37-year-old woman's momentary gender transformations include the sense that her voice is deeper and her arms have become hairier. On one occasion, she told the researchers, a female friend was in the room as a seizure came on, and she had the sense that her friend had become a male as well. A magnetic resonance imaging scan revealed damage to the woman's right amygdala, probably caused by a small tumor, and EEG electrodes recorded abnormal activity in the surrounding right temporal lobe, suggesting that this region is the source of her seizures. Other than some symptoms of depression and anxiety, which responded well to treatment, the woman had no history of psychiatric illness, and she never experienced the transformation in the absence of seizures. Delusional feelings of gender transformation have been previously reported in people with schizophrenia and other psychotic illnesses, the authors write, but not to their knowledge in a person with epilepsy. © 2009 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Epilepsy
Link ID: 13215 - Posted: 06.24.2010

About 50,000 people have been diagnosed with narcolepsy in the U.S, but there may be as many as 2.4 million people unknowingly living with it. Narcolepsy causes excessive daytime sleepiness, fatigue and even sudden muscular weakness, known as cataplexy. Here, six men and women speak about living with narcolepsy. Copyright 2009 The New York Times Company

Keyword: Narcolepsy; Sleep
Link ID: 13214 - Posted: 08.27.2009

Getting high blood pressure under control could potentially help prevent memory troubles, U.S. researchers say. People aged 45 and older with high diastolic blood pressure — high readings on the bottom number of the blood pressure reading — were more likely to have problems with their memory and thinking skills than those with normal readings, the team reported in Tuesday's issue of the journal Neurology. Every 10-point increase in the reading was associated with seven per cent higher odds of cognitive impairment, which can be a precursor to dementia, the researchers said. "Higher diastolic blood pressure was cross-sectionally and independently associated with impaired cognitive status in this large, geographically dispersed, race- and sex-balanced sample of stroke-free individuals," the researchers concluded in the study. The finding held after researchers accounted for other factors that could affect thinking skills, such as age, education level, smoking and other illnesses such as diabetes. "It's possible that by preventing or treating high blood pressure, we could potentially prevent cognitive impairment, which can be a precursor to dementia," Dr. Georgios Tsivgoulis of the University of Alabama at Birmingham, who led the study, said in a statement. © CBC 2009

Keyword: Learning & Memory; Stress
Link ID: 13213 - Posted: 06.24.2010

David Perlman, Chronicle Science Editor Once upon a time in the long evolution of Homo sapiens, a band of our African ancestors learned to use fire for more than cooking meat, lighting the dark or warding off attacking animals. Those Stone Age people became the world's first engineers - they discovered that the intense heat of a fire's embers could make chunks of stone much easier to flake for making tools, and to make them much sharper too. It was "a breakthrough adaptation in human evolution," reports an international group of archaeologists and anthropologists. And it may have come about because of changes in those early human's brains, other scientists say. What began at least 165,000 years ago became the most common method of stone toolmaking in Africa by about 72,000 years ago. The scientists from Africa, Australia and Arizona analyzed nearly 200 ancient tools found around cave dwellings at a South African coastal site called Pinnacle Point, which earlier excavations had shown were inhabited by people of the Middle Stone Age. The knives, scrapers and hand axes were made of a widely used type of silicate rock called silcrete. Some of the scientists, reporting in the current issue of the journal Science, are themselves skilled at "knapping" - the art of chipping stones by hand to create sharp tools - and their tools demonstrated the clear improvements possible from heat treatment at fire temperatures of 450 Fahrenheit or more. © 2009 Hearst Communications Inc.

Keyword: Evolution
Link ID: 13212 - Posted: 06.24.2010

Rossella Lorenzi, Discovery News -- The remains of a man who could be the world's oldest known paralysis victim have been unearthed by Australian bio-archaeologists in northern Vietnam. Found at the Neolithic cemetery site of Man Bac, some 100 kilometers (62 miles) south of Hanoi, the remains are between 3,500 and 4,000 years old and belong to an adult male who died around age 25. Called Man Bac Burial 9, or simply M9, the young man suffered from paraplegia or possibly quadriplegia due to a rare disorder called Klippel-Feil Syndrome, a condition involving congenital fusion of the spine. The disorder, which can make sufferers look as if they have a short neck, is also often associated with various complications. In the case of M9, posture-related complications forced his head to tilt to his right side, a condition known as torticollis. M9 also likely had problems chewing. spine surgery "Amazingly, this man survived in a subsistence Neolithic economy with total lower body paralysis, and at best minimal upper body mobility for at least a decade prior to death," Lorna Tilley, the Australian National University Ph.D. candidate who excavated the remains with lead researcher Marc Oxenham, told Discovery News. © 2009 Discovery Communications, LLC. Inc.

Keyword: Movement Disorders; Evolution
Link ID: 13211 - Posted: 06.24.2010

By Larry Greenemeier Huber, Purdue, Moran, Parkinson'sParkinson's disease sufferers typically face a long, difficult battle against the disorder's degenerative effects on their motor skills and speech. While many scientists are studying the potential for drugs, surgery and exercise to slow the disease's impact on the central nervous system—including tremors, stiff muscles and impaired movement—one team of researchers is experimenting with technology designed to help Parkinson's sufferers fend off voice and speech problems. Parkinson's can leave its victims afflicted with speech that tends to be soft, hoarse and monotonous, particularly during the disease's later stages. Jessica Huber, an associate professor of speech, language and hearing sciences at Purdue University in West Lafayette, Ind., is in the early stages of developing a device that could help Parkinson's sufferers articulate their thoughts more audibly by exploiting the Lombard effect, a reflex in which people automatically speak louder in the presence of background sound (for example, at a sporting event, party or restaurant). Huber has created device that includes an earpiece that automatically plays ambient noise, mimicking the din of conversation typically found in a restaurant, whenever a person attempts to speak (this is detected by a sensor placed on the neck). A mask and sensors in elastic bands placed around the rib cage precisely record respiratory, laryngeal and articulatory data as the subject speaks. © 1996-2009 Scientific American Inc.

Keyword: Parkinsons; Language
Link ID: 13210 - Posted: 06.24.2010

By Robert Epstein and Jennifer Ong Thrill seeking and poor judgment go hand in hand when it comes to teenagers—an inevitable part of human development determined by properties of a growing but immature brain. Right? Not so fast. A study being published tomorrow turns that thinking upside down: The brains of teens who behave dangerously are more like adult brains than are those of their more cautious peers. Psychologists have long believed that the brain's judgment-control systems develop more slowly than emotion-governing systems, not maturing until people are in their mid-20s. Hence, teens end up taking far more risks than adults do. Evidence supporting this idea comes from studies looking at functional and structural properties of gray matter, the important part of the brain that contains the neurons that relay brain signals. At least two observations undermine this theory, however. First, American-style teen turmoil is absent in more than 100 cultures around the world, suggesting that such mayhem is not biologically inevitable. Second, the brain itself changes in response to experiences, raising the question of whether adolescent brain characteristics are the cause of teen tumult or rather the result of lifestyle and experiences. Because brain research is virtually always correlational in design, determining whether brain properties are causes or effects is impossible. Now neuroscientists Gregory S. Berns, Sara Moore and Monica Capra of Emory University suggest that teen risk-taking is associated not with an immature brain but with a mature, adultlike brain—exactly the opposite of conventional wisdom. © 1996-2009 Scientific American Inc.

Keyword: Development of the Brain; Brain imaging
Link ID: 13209 - Posted: 06.24.2010

By Paul W. Andrews and J. Anderson Thomson, Jr. Depression seems to pose an evolutionary paradox. Research in the US and other countries estimates that between 30 to 50 percent of people have met current psychiatric diagnostic criteria for major depressive disorder sometime in their lives. But the brain plays crucial roles in promoting survival and reproduction, so the pressures of evolution should have left our brains resistant to such high rates of malfunction. Mental disorders should generally be rare — why isn’t depression? This paradox could be resolved if depression were a problem of growing old. The functioning of all body systems and organs, including the brain, tends to deteriorate with age. This is not a satisfactory explanation for depression, however, as people are most likely to experience their first bout in adolescence and young adulthood. Or, perhaps, depression might be like obesity — a problem that arises because modern conditions are so different from those in which we evolved. Homo sapiens did not evolve with cookies and soda at the fingertips. Yet this is not a satisfactory explanation either. The symptoms of depression have been found in every culture which has been carefully examined, including small-scale societies, such as the Ache of Paraguay and the !Kung of southern Africa — societies where people are thought to live in environments similar to those that prevailed in our evolutionary past. There is another possibility: that, in most instances, depression should not be thought of as a disorder at all. In an article recently published in Psychological Review, we argue that depression is in fact an adaptation, a state of mind which brings real costs, but also brings real benefits. © 1996-2009 Scientific American Inc.

Keyword: Depression; Evolution
Link ID: 13208 - Posted: 06.24.2010