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

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

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

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

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

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

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

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

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

Keyword: ADHD
Link ID: 13175 - Posted: 06.24.2010

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

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

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

Keyword: Stress
Link ID: 13173 - Posted: 06.24.2010

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

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

Women who are optimistic have a lower risk of heart disease and death, an American study shows. The latest study by US investigators mirrors the findings of earlier work by a Dutch team showing optimism reduces heart risk in men. The research on nearly 100,000 women, published in the journal Circulation, found pessimists had higher blood pressure and cholesterol. Even taking these risk factors into account, attitude alone altered risks. Optimistic women had a 9% lower risk of developing heart disease and a 14% lower risk of dying from any cause after more than eight years of follow-up. In comparison, cynical women who harboured hostile thoughts about others or were generally mistrusting of others were 16% more likely to die over the same time-scale. One possibility is that optimists are better at coping with adversity, and might, for example take better care of themselves when they do fall ill. In the study, the optimistic women exercised more and were leaner than pessimistic peers. Lead researcher Dr Hilary Tindle, assistant professor of medicine at the University of Pittsburgh, said: "The majority of evidence suggests that sustained, high degrees of negativity are hazardous to health." A spokeswoman for the British Heart Foundation said: "We know that hostile emotions can release certain chemicals in the body which may increase the risk of heart disease, but we don't fully understand how and why. (C)BBC

Keyword: Emotions; Stress
Link ID: 13171 - Posted: 08.17.2009

By RONI CARYN RABIN Elderly people who are physically active appear to be at lower risk of developing Alzheimer’s disease, as are those who eat a heart-healthy Mediterranean style diet, rich in fruits and vegetables and low in red meat. Now, a new study has found that the effects of the two lifestyle behaviors are independent — and the benefits add up. The Columbia University study followed a diverse group of 1,880 septuagenarian New Yorkers, assessing their diets and levels of physical activity, and screening them periodically for Alzheimer’s disease. After an average of five years, 282 cases of Alzheimer’s were diagnosed. Those who followed the healthiest diets were 40 percent less likely to develop Alzheimer’s than those with the worst diets, and those who got the most exercise were 37 percent less likely to develop the disease than those who got none. But the greatest benefits occurred in those who both ate healthy and remained active. Participants who scored in the top one-third for both diet and exercise were 59 percent less likely to be diagnosed with Alzheimer’s than those who scored in the lowest one-third. While one in 5 participants with the lowest scores developed Alzheimer’s, fewer than one in 10 of the top scorers developed the disease. Copyright 2009 The New York Times Company

Keyword: Alzheimers
Link ID: 13170 - Posted: 06.24.2010

Daniel H. Silverman, M.D., Ph.D. Personal Health columnist Jane Brody recently wrote about chemo brain, the sometimes prolonged mental fogginess that can follow cancer treatments, in “The Fog That Follows Chemotherapy” and “Taking Steps to Cope With Chemo Brain.” Dr. Daniel Silverman, a leading researcher in the field and co-author of “Your Brain on Chemo,” joined the Consults blog to answer readers’ questions. Here, Dr. Silverman responds to two readers’ concerns about chemotherapy, Alzheimer’s disease and attention deficit disorder. Q. Is There a Link Between Cancer Treatment and Alzheimer’s? Dr. Silverman responds: Sally, you have brought up what are really four related great questions that are of critical pertinence to the ultimate welfare of your sister, as well as of literally tens of thousands of older cancer patients who have received chemotherapy, and have subsequently been diagnosed with Alzheimer’s disease: The most important thing to realize is that, no matter how confident your sisters’ neurologists may be that she has Alzheimer’s disease, there’s a very good chance that they’re wrong — unless your sister has undergone biological testing that is specific for Alzheimer’s disease. Such tests might include a biopsy of her brain tissue, a lumbar puncture to extract and analyze cerebrospinal fluid, and/or (least invasively) a brain PET scan that has been interpreted by someone with specific expertise in reading that kind of scan. Copyright 2009 The New York Times Company

Keyword: Alzheimers
Link ID: 13169 - Posted: 06.24.2010

by Andy Coghlan Women: do you have a man? If you do, better beware. Chances are that some lone female has her eye on him. A new study provides evidence for what many have long suspected: that single women are much keener on pursuing a man who's already taken than a singleton. "The single women really, really liked the guy when he was taken," says Melissa Burkley of Oklahoma State University in Stillwater, who conducted the "mate-poaching" study with her colleague Jessica Parker. They asked 184 heterosexual students at the university to participate in a study on sexual attraction and told the volunteers that a computer program would match them with an ideal partner. Half the participants were single and half attached, with equal numbers of men and women in each group. Unknown to the participants, everyone was offered a fictitious candidate partner who had been tailored to match their interests exactly. The photograph of "Mr Right" was the same for all women participants, as was that of the ideal women presented to the men. Half the participants were told their ideal mate was single, and the other half that he or she was already in a romantic relationship. "Everything was the same across all participants, except whether their ideal mate was already attached or not," says Burkley. Journal reference: Journal of Experimental Social Psychology, DOI: 10.1016/j.jesp.2009.04.022

Keyword: Sexual Behavior; Evolution
Link ID: 13168 - Posted: 08.17.2009

By Katherine Harmon Gene therapy has been rhapsodized and vilified in its nearly two decades of human testing, helping some and making others sicker. But a new 12-month clinical trial has shown that, at least in one ocular disease, it appears safe and—perhaps even more impressive—effective. The research, part of a phase I clinical trial to test the safety of the treatment, was published as a letter to the editor in The New England Journal of Medicine earlier this week and will be in the September issue of Human Gene Therapy. (The paper was co-authored by about a dozen researchers, two of whom own equity in a company that could profit from a commercialized version of this procedure.) The researchers report that three young adults with severe vision impairment from a hereditary disease maintained improved eyesight a year after gene therapy was administered—and didn't suffer any health side effects in the meantime. Gene therapy, which often employs viruses to deliver the good genes to a body's target cells, has been known to trigger severe immune responses and was blamed for the death of an 18-year-old in 1999, who was receiving gene therapy for a hereditary metabolic disorder. The test subjects suffer from Leber congenital amaurosis (LCA), a form of hereditary retinal degeneration that occurs in infants and young children and is relatively rare. Most people who have lost vision due to hereditary retinal degeneration have either no photoreceptors with which to perceive light or photoreceptors that don't work. "This disease has a little bit of both," explains lead study author Artur Cideciyan, an associate research professor at the Scheie Eye Institute at the University of Pennsylvania. "It's a complex disease." © 1996-2009 Scientific American Inc.

Keyword: Vision; Genes & Behavior
Link ID: 13167 - Posted: 06.24.2010

By Vilayanur S. Ramachandran and Diane Rogers-Ramachandran All primates, including humans, have two eyes facing forward. With this binocular vision, the views through the two eyes are nearly identical. In contrast, many other animal groups, especially herbivores such as ungulates (hooved animals, including cows, sheep and deer) and lagomorphs (rabbits, for example), have eyes pointing sideways. This perspective provides largely independent views for each eye and an enormously enlarged field of view overall. Why did primates sacrifice panoram­ic vision? What benefit did they gain? We know binocular vision evolved several times independently in vertebrates. For example, among birds, predatory species such as owls and hawks have forward-pointing eyes. One theory is that the feature conferred a statistical advantage—two eyes are better than one—for detecting and discriminating objects, such as prey, in low light levels. But whatever the original reason for its emergence, the evolutionary novelty afforded a huge advantage: stereoscopic (literally, solid) vision. How does it work? Even though both your eyes point forward, they are separated horizontally so that they look at the world from two slightly different vantage points. It follows that each eye receives a slightly different picture of the three-dimensional scene around you; the differences (called retinal disparities) are proportional to the relative distances of the objects from you. Try this quick experiment to see what we mean: hold two fingers up, one in front of the other. Now, while fixating on the closer finger, alternately open and close each eye. You’ll notice that the farther the far finger is from you (don’t move the near finger), the greater the lateral shift in its position as you open and close each eye. On the retinas, this difference in line-of-sight shift manifests itself as disparity between the left and right eye images. © 1996-2009 Scientific American Inc.

Keyword: Vision
Link ID: 13166 - Posted: 06.24.2010

By Judith Burns A new study suggests that people from different cultures read facial expressions differently. East Asian participants in the study focused mostly on the eyes, but those from the West scanned the whole face. In the research carried out by a team from Glasgow University, East Asian observers found it more difficult to distinguish some facial expressions. The work published in Current Biology journal challenges the idea facial expressions are universally understood. In the study, East Asians were more likely than Westerners to read the expression for "fear" as "surprise", and "disgust" as "anger". The researchers say the confusion arises because people from different cultural groups observe different parts of the face when interpreting expression. East Asians participants tended to focus on the eyes of the other person, while Western subjects took in the whole face, including the eyes and the mouth. Co-author, Dr Rachael Jack, from the University of Glasgow, said: "Interestingly, although the eye region is ambiguous, subjects tended to bias their judgements towards less socially-threatening emotions - surprise rather than fear, for example. "This perhaps highlights cultural differences when it comes to the social acceptability of emotions." The team showed 13 Western Caucasians and 13 East Asians a set of standardised images depicting the seven main facial expressions: happy, sad, neutral, angry, disgusted, fearful and surprised. (C)BBC

Keyword: Emotions; Evolution
Link ID: 13165 - Posted: 08.15.2009

By Jenny Lauren Lee You are hiking in the mountains when, out of the corner of your eye, you see something suspiciously snakelike. You freeze and look more carefully, this time identifying the source of your terror: a stick. Yet you could have sworn it was a snake. The brain may play tricks, but in this case it was actually doing you a favor. The context — a mountain trail — was right for a snake. So your brain was primed to see one. And the stick was sufficiently snakelike to make your brain jump to a visual conclusion. But it turns out emotions are involved here, too. A fear of snakes means that given an overwhelming number of items to look at — rocks, shrubs, a hiking buddy — “snake” would take precedence. Studies show that the brain guesses the identity of objects before it has finished processing all the sensory information collected by the eyes. And now there is evidence that how you feel may play a part in this guessing game. A number of recent studies show that these two phenomena — the formation of an expectation about what one will see based on context and the visual precedence that emotions give to certain objects — may be related. In fact, they may be inseparable. New evidence suggests that the brain uses “affect” (pronounced AFF-ect) — a concept researchers use to talk about emotion in a cleaner, more clearly defined way — not only to tell whether an object is important enough to merit further attention, but also to see that object in the first place. © Society for Science & the Public 2000 - 2009

Keyword: Emotions; Vision
Link ID: 13164 - Posted: 06.24.2010

By Elizabeth Pennisi Imitation may be the sincerest form of flattery, but it's also a good way to make friends. People warm up to us when we unconsciously mimic them. Now, it turns out that capuchin monkeys also favor people who "flatter" them with imitation--the first time the behavior has been seen in nonhumans. "This work is really important because it shows that human social interaction ... [is] rooted in very implicit evolutionarily ancient processes," says Laurie Santos, a psychologist at Yale University. Researchers speculate that, because imitation seems to foster friendship in humans, it helps maintain the peaceful relationships that have been essential to the success of our species. Humans aren't the only social animal, however, and psychologist Annika Paukner wondered whether other primates share the imitation-friendship connection. Paukner and colleagues at the National Institute of Child Health and Human Development in Poolesville, Maryland, focused on capuchin monkeys, which live in highly social groups of 30 to 40 animals. They placed a monkey in the middle of three interconnected cages, while a person stood in front of each of the end cages. The monkey and the two people each had a small ball: One person poked, mouthed, and pounded the ball randomly; the other mimicked whatever the monkey did with the ball. Like humans, the monkeys seemed drawn to the imitation. After watching the two people for just a few minutes, the capuchins spent twice as much time looking at the imitator and almost 38% of the test period sitting directly in front of the imitator, compared with 27% in front of the other person. When the people switched places, the monkey tended to shift cages as well, showing a greater affiliation for the imitator.

Keyword: Emotions; Evolution
Link ID: 13163 - Posted: 08.15.2009

By TARA PARKER-POPE Researchers have found a genetic mutation in two people who need far less sleep than average, a discovery that might open the door to understanding human sleep patterns and lead to treatments for insomnia and other sleep disorders. The finding, published in the Friday issue of the journal Science, marks the first time scientists have identified a genetic mutation that relates to sleep duration in any animal or human. Although the mutation has been identified in only two people, the power of the research stems from the fact that the shortened sleep effect was replicated in mouse and fruit-fly studies. As a result, the research now gives scientists a clearer sense of where to look for genetic traits linked to sleep patterns. “I think it’s really a landmark study,” said Dr. Charles A. Czeisler, a leading sleep researcher and chief of sleep medicine at Brigham and Women’s Hospital in Boston. “It opens up a window to the understanding of the genetic basis of individual differences in sleep duration. Now you have a piece of the puzzle and you can begin to try to trace back as opposed to having little information as to where to start.” The gene mutation was found by scientists at the University of California, San Francisco, who were conducting DNA screening on several hundred blood samples from people who had taken part in sleep studies. Copyright 2009 The New York Times Company

Keyword: Sleep; Genes & Behavior
Link ID: 13162 - Posted: 06.24.2010

Colin Ellard is an associate professor of psychology at the University of Waterloo and the director of the university’s Research Laboratory for Immersive Virtual Environments, which is devoted to studies of the psychology of space, especially as it pertains to architecture, planning and design. He is also the author of You Are Here, a new book about the emerging psychology of direction. Mind Matters editor Gareth Cook chatted with him about the surprising ways we misunderstand the world around us. COOK: In your book, you pose the question: Which city is farther west, Reno or Los Angeles. Can you please explain? ELLARD: I based this question on some interesting research done by Barbara Tversky in which she showed that most people answer this question by saying that LA is farther west. This happens because our minds play all kinds of tricks to schematize space -- that is, to reduce complicated spatial relationships to very simple ones by aligning things that aren't aligned, straightening things that are curved, and grouping things together in ways that may not reflect reality. (California is west of Nevada so therefore everything in California must be west of everything in Nevada -- but it's not). The tricks are there for a very good reason -- they can help us to organize memories for spaces, but they can also let us down sometimes. COOK: I have looked at a map, and, honestly, I am still having trouble believing it is true... ELLARD: I'm laughing here because I actually had to fire up Google Maps to be sure I had this right. And I wrote the book! It's a testament to the power of these mental space-warping tools of ours that even when we understand how they work we still fall prey to them. © 1996-2009 Scientific American Inc.

Keyword: Miscellaneous
Link ID: 13161 - Posted: 06.24.2010

By Tina Hesman Saey Human see. Human do. As with monkeys, it’s apparently the same for some nerve cells in the brain. Macaque monkeys have specialized brain cells — called mirror neurons — that activate when a monkey performs an action involving an object, such as picking up a grape, or when watching someone else do the same task. The discovery of these neurons in 1996 led to speculation that they could be involved in everything from simulating others’ actions to language development to autism. There was only one problem: no one had definite proof that such cells exist in humans. Now a new study in the Aug. 12 Journal of Neuroscience provides strong evidence that humans have mirror neurons too. Researchers used functional MRI to examine volunteers’ brains for signs of mirror neurons. While in a scanner, volunteers either performed two different types of grips — a precision grip or putting a finger through a ring and pulling the ring — or watched videos of someone else making the movements. Groups of neurons in a part of the brain called the inferior frontal gyrus responded both to watching and doing the same action, researchers led by James Kilner, a neuroscientist at the Wellcome Trust Center for Neuroimaging at University College London in England, reported. Other groups have tried various techniques to discover human mirror neurons, but without success. Those groups had used volunteers perform or imitate that didn’t involve objects, such as playing rock, paper, scissors or making undirected motions. But interactions with objects are necessary to activate mirror neurons in monkeys, says Scott Grafton, a cognitive neuroscientist at the University of California, Santa Barbara. Kilner succeeded in finding the neurons because his experiments explored the interaction between movements and objects, Grafton says. © Society for Science & the Public 2000 - 2009

Keyword: Vision; Autism
Link ID: 13160 - Posted: 06.24.2010