By Katie Moisse More than 15 years after a genetic variant was shown to predispose its carriers to schizophrenia, scientists have finally uncovered how the chromosomal abnormality might cause symptoms of the brain disorder. By studying mice with a similar gene defect, the research team from Columbia University Medical Center linked abnormalities in behavior to a faulty connection between the hippocampus and the prefrontal cortex—two brain areas important for learning and memory. "We know that this genetic deficit predisposes us to schizophrenia, and now we have identified a clear pathophysiological mechanism of how [it] confers this risk…," Maria Karayiorgou, co-author on the study published April 1 in Nature and lead author on the 1994 publication identifying the genetic variant in Brain Research, said in a prepared statement. (Scientific American is part of Nature Publishing Group.) Thirty percent of people carrying the variant—a small deletion of genetic material on chromosome 22—will go on to develop the schizophrenia, making it "one of largest genetic risk factors" for the disease, according to senior author Joshua Gordon. The odds of someone in the general U.S. population developing the disorder are one in 100, but those odds jump to one in 10 for people with an affected first-degree relative, and one in three for people with a schizophrenic identical twin, highlighting the role of genes in the development of the disease. © 2010 Scientific American,

Keyword: Schizophrenia; Genes & Behavior
Link ID: 13933 - Posted: 06.24.2010

by MacGregor Campbell "THE leg wasn't bouncing all over the table, but there were substantial twitches," says Matthew Schiefer, a neural engineer at Case Western Reserve University in Cleveland, Ohio. Schiefer is describing an experiment in which pulses of electricity are used to control the muscles of an unconscious patient, as if they were a marionette. It represents the beginnings of a new generation of devices that he hopes will allow people with paralysed legs to regain control of their muscles and so be able to stand, or even walk again. His is one of a raft of gadgets being developed that plug into the network of nerves that normally relay commands from the spinal cord to the muscles, but fall silent when a spinal injury breaks the chain. New ways to connect wires to nerves (see diagram) allow artificial messages to be injected to selectively control muscles just as if the signal had originated in the brain. Limbs that might otherwise never again be controlled by their owners can be brought back to life. The potential of this approach was demonstrated in 2006 when a different Case Western team enabled someone who was paralysed from the waist down to watch their usually motionless knees straighten at the push of a button. With a little support they even stood for 2 minutes while signals injected into nerves in their thighs kept their knees straight. © Copyright Reed Business Information Ltd

Keyword: Regeneration
Link ID: 13932 - Posted: 06.24.2010

By GINA KOLATA Dr. Bastiaan R. Bloem of the Radboud University Nijmegen Medical Center in the Netherlands thought he had seen it all in his years of caring for patients with Parkinson’s disease. But the 58-year-old man who came to see him recently was a total surprise. A video from the Netherlands of a 58-year-old man with a 10-year history of Parkinson’s disease showed him freezing in his movements after a few steps. Yet he was able to ride a bicycle. The man had had Parkinson’s disease for 10 years, and it had progressed until he was severely affected. Parkinson’s, a neurological disorder in which some of the brain cells that control movement die, had made him unable to walk. He trembled and could walk only a few steps before falling. He froze in place, his feet feeling as if they were bolted to the floor. But the man told Dr. Bloem something amazing: he said he was a regular exerciser — a cyclist, in fact — something that should not be possible for patients at his stage of the disease, Dr. Bloem thought. “He said, ‘Just yesterday I rode my bicycle for 10 kilometers’ — six miles,” Dr. Bloem said. “He said he rides his bicycle for miles and miles every day.” “I said, ‘This cannot be,’ ” Dr. Bloem, a professor of neurology and medical director of the hospital’s Parkinson’s Center, recalled in a telephone interview. “This man has end-stage Parkinson’s disease. He is unable to walk.” Copyright 2010 The New York Times Company

Keyword: Parkinsons
Link ID: 13931 - Posted: 06.24.2010

By Carolyn Y. Johnson The pungent sting of wasabi, the searing pain of tear gas, and the watery eyes we get from chopping an onion are all triggered by an ancient chemical sensor that is found in everything from humans to mollusks and may hold the key to developing new kinds of insect repellents and pain medications. Research by Brandeis University scientists finds that the ability to detect noxious compounds comes from a biological pathway older than our sense of smell, emerging far in the evolutionary past, about half a billion years ago. “This chemical sense, as far as we can tell, appears to have been essentially unchanged,’’ said Paul Garrity, a biology professor at Brandeis and senior author of a paper published in the journal Nature this month. The sensor’s ubiquity and stability suggested it does something essential for the survival of animals, but what? For years, researchers had been interested in the sensor, a molecule called TRPA1 that is known to be involved in pain perception. It responds to chemicals that can damage tissue, such as ingredients in wasabi or cigarette smoke. Those chemicals are created by many plants to ward off predators that might chew on their leaves. Researchers interested in finding ways to dampen pain had studied the sensor, which occurs in humans. But they did not know why the chemical sensor existed in the first place. © 2010 NY Times Co.

Keyword: Chemical Senses (Smell & Taste); Emotions
Link ID: 13930 - Posted: 06.24.2010

By PATRICIA COHEN To illustrate what a growing number of literary scholars consider the most exciting area of new research, Lisa Zunshine, a professor of English at Kentucky University, refers to an episode from the TV series “Friends.” (Follow closely now; this is about the science of English.) Phoebe and Rachel plot to play a joke on Monica and Chandler after they learn the two are secretly dating. The couple discover the prank and try to turn the tables, but Phoebe realizes this turnabout and once again tries to outwit them. As Phoebe tells Rachel, “They don’t know that we know they know we know.” This layered process of figuring out what someone else is thinking — of mind reading — is both a common literary device and an essential survival skill. Why human beings are equipped with this capacity and what particular brain functions enable them to do it are questions that have occupied primarily cognitive psychologists. Now English professors and graduate students are asking them too. They say they’re convinced science not only offers unexpected insights into individual texts, but that it may help to answer fundamental questions about literature’s very existence: Why do we read fiction? Why do we care so passionately about nonexistent characters? What underlying mental processes are activated when we read? Ms. Zunshine, whose specialty is 18th-century British literature, became familiar with the work of evolutionary psychologists while she was a graduate student at Stanford in the 1990s. “I thought this could be the most exciting thing I could ever learn,” she said. Copyright 2010 The New York Times Company

Keyword: Language; Brain imaging
Link ID: 13929 - Posted: 06.24.2010

By Tina Hesman Saey Zebra finches have something to tweet about. The little songbirds’ genetic instruction book has just been deciphered. An international team of scientists announced the accomplishment in the April 1 Nature. Zebra finches are the first songbirds and the second bird, after the chicken, with a completely decoded genetic blueprint. Contained within the finch’s DNA could be clues to how songbirds learn vocal information and use songs in social situations, a model for human language and communication. Whales, dolphins, some bats and several other species of birds also learn vocally, but the mouse-sized zebra finch has become a model system for studying the process in the laboratory. Male zebra finches memorize their fathers’ songs and practice singing the song for a month or two. Once learned, a male’s song is his signature. Unlike other songbirds that can change their songs, he sings his for life. Discovering the molecular mechanisms behind how songbirds learn their songs could also help scientists better understand human communication disorders such as autism and stuttering, says David Clayton, a neurobiologist at the University of Illinois at Urbana-Champaign, who was one of the leaders of the study. Neuroscientists have studied zebra finches for years to learn which parts of the birds’ brains become active as the animals hear and learn new songs. The new genetic information will add molecular details to help scientists better understand vocal learning, says Allison Doupe, a neuroscientist and psychiatrist at the University of California, San Francisco. She was not involved in the new study, but says the genetic information is a welcome tool for researchers who study the finches. © Society for Science & the Public 2000 - 2010

Keyword: Animal Communication; Genes & Behavior
Link ID: 13928 - Posted: 06.24.2010

by Lauren Schenkman Birds do it, monkeys do it, humans do it-learning from the individuals around you is a crucial skill if you want to survive in a group. Scientists have thought that the ability to learn from others evolved in step with communal living. Now a study demonstrates an exception: A solitary reptile is an adept social learner. From the time young red-footed tortoises (Geochelone carbonaria) hatch in their native South American rainforests, they are alone. They grow up without parents or siblings, and adults rarely cross paths. If a head-bobbing display determines that a stranger is of the opposite sex, the two will mate perfunctorily-otherwise they just ignore each other. In a species so uninterested in social interactions, it's hard to see how the ability to learn from others could have evolved, says Anna Wilkinson, a cognitive biologist at the University of Vienna. But one day she scattered dandelions, a favorite snack, near a female tortoise named Wilhelmina, who began to eat. A second tortoise ignored a clump that had fallen near him and followed Wilhelmina to her clump instead. This made Wilkinson wonder whether the second tortoise had "learned that the dandelions were there" by observing where Wilhelmina was eating. So Wilkinson set out to test whether tortoises learned a navigation task better by watching other tortoises or on their own. She set up a v-shaped wire fence and placed a bowl containing a few tidbits of strawberry and mushroom inside the fence at the point of the "V". Then she set Wilhelmina outside the tip of the "V", with the treats on the other side of the fence. In 12 trials, Wilhelmina tried to force her way through the barrier but never tried to walk around. The same was true of three other control tortoises Wilkinson and her colleagues tested. "In later trials, they would ... go up the arm [of the "V"] and go to sleep," says Wilkinson. © 2010 American Association for the Advancement of Science.

Keyword: Learning & Memory
Link ID: 13927 - Posted: 06.24.2010

The strongest known recurrent genetic cause of schizophrenia (http://www.nimh.nih.gov/health/topics/schizophrenia/index.shtml) impairs communications between the brain’s decision-making and memory hubs, resulting in working memory deficits, according to a study in mice. Researchers have suspected such a brain connectivity disturbance in schizophrenia for more than a century, and the NIH has launched a new initiative on the brain’s functional circuitry, or connectome (http://www.nimh.nih.gov/about/director/2010/tracing-the-brains-connections.shtml). Although the disorder is thought to be 70 percent heritable, its genetics are dauntingly complex (http://www.nimh.nih.gov/science-news/2009/schizophrenia-and-bipolar-disorder-share-genetic-roots.shtml), except in certain rare cases, such as those traced to the mutation in question. Still, the mutation's link to the disturbed connectivity and working memory deficit eluded detection until now. To explore the mutation's effects on brain circuitry, Gogos, Karayiorgou and colleagues engineered a line of mice expressing the same missing segment of genetic material as the patients. Strikingly, like their human counterparts with schizophrenia, these animals turned out to have difficulty with working memory tasks — holding information in mind from moment to moment.

Keyword: Schizophrenia; Genes & Behavior
Link ID: 13926 - Posted: 06.24.2010

So a scientist walks into a shopping mall to watch people laugh. There's no punchline. Laughter is a serious scientific subject, one that researchers are still trying to figure out. Laughing is primal, our first way of communicating. Apes laugh. So do dogs and rats. Babies laugh long before they speak. No one teaches you how to laugh. You just do. And often you laugh involuntarily, in a specific rhythm and in certain spots in conversation. You may laugh at a prank on April Fools' Day. But surprisingly, only 10 to 15 percent of laughter is the result of someone making a joke, said Baltimore neuroscientist Robert Provine, who has studied laughter for decades. Laughter is mostly about social responses rather than reaction to a joke. "Laughter above all else is a social thing," Provine said. "The requirement for laughter is another person." Over the years, Provine, a professor with the University of Maryland Baltimore County, has boiled laughter down to its basics. "All language groups laugh 'ha-ha-ha' basically the same way," he said. "Whether you speak Mandarin, French or English, everyone will understand laughter. ... There's a pattern generator in our brain that produces this sound." Each "ha" is about one-15th of a second, repeated every fifth of a second, he said. Laugh faster or slower than that and it sounds more like panting or something else. © 2010 Discovery Communications, LLC

Keyword: Emotions
Link ID: 13925 - Posted: 06.24.2010

by Emma Young MEMORIES are the basic stuff of thought. We access our stores of knowledge every time we perform a task, communicate through speech or formulate the simplest concepts. Yet the physical form of memory has long been mysterious. What changes occur in the brain when a new memory is encoded? One thing we do know is that memory formation involves the strengthening of synaptic connections between nerve cells. Using sea slugs, which have a relatively simple nervous system, a team led by Kelsey Martin at the University of California, Los Angeles, last year became the first to watch memories being made, in the form of new proteins appearing at the synapses (Science, vol 324, p 1536). Where, though, is knowledge stored in the complex brains of mammals? Short-term memories, such as a telephone number about to be used, seem to be stored in two small curled-up structures called the hippocampi, buried deep in the brain's two hemispheres. In 2008 Courtney Miller and David Sweatt at the University of Alabama in Tuscaloosa showed in mice that during the first hour after a memorable event there were chemical changes to the DNA of neurons in this area, altering the proteins produced. Over the subsequent week, there were similar changes to the genes of neurons in the cortex. These changes seemed to be permanent, indicating that long-term memories are stored there (Neuron, volume 53, p 857). The pair think they watched short-term memories form in the hippocampus, which then became long-term memories in the cortex. © Copyright Reed Business Information Ltd

Keyword: Learning & Memory
Link ID: 13924 - Posted: 06.24.2010

by James Mitchell Crow YOU were born with all the brain cells you'll ever have, so the saying goes. So much for sayings. In the 1990s, decades of dogma were overturned by the discovery that mammals, including people, make new neurons throughout their lives. In humans, such "neurogenesis" has been seen in two places: neurons formed in the olfactory bulb seem to be involved in learning new smells, while those born in the hippocampus are involved in learning and memory. The discovery that new neurons can integrate into the adult brain raises intriguing possibilities. Could the process be harnessed to treat diseases of the brain, such as Parkinson's and Alzheimer's? The trick will be in replacing diseased cells with just the right kind of neuron, says Jeff Macklis, who studies neurogenesis at the Massachusetts Institute of Technology. By some estimates, the nervous system is made up of 10,000 different kinds of neuron. This complexity means you can't just hijack any old cell produced by natural neurogenesis. However, there may be other ways of growing new neurons to order. Olle Lindvall at Lund University in Sweden has shown what might be possible. He transplanted dopamine-producing neurons taken from aborted fetuses into the brains of people with Parkinson's, and showed the new neurons can improve brain function, although the treatment didn't work for everyone. Lindvall is now looking for ways to make these specialised neurons from embryonic stem cells or stem cells made by reprogramming adult skin cells. © Copyright Reed Business Information Ltd

Keyword: Regeneration; Neurogenesis
Link ID: 13923 - Posted: 06.24.2010

by Helen Thomson "WHEN you're smilin', the whole world smiles with you," sang Louis Armstrong. He could have been referring to what some consider one of the greatest recent discoveries of neuroscience: mirror neurons. Discovered in macaques in the 1990s, these cells were spotted when researchers made recordings from microelectrodes placed in the animals' brains as they performed various tasks. While many neurons fired when the animal performed an action, a subset also fired when the animals saw the researcher perform the same action, with different groups of mirror neurons for different actions. Neuroscientists have speculated that in people, mirror neurons could represent the neural basis of empathy. They could also contribute to imitation and learning, and perhaps even language acquisition. It has been hard to find out if people have mirror neurons, but MRI scans have shown that certain areas of the brain - dubbed mirror systems - "light up" when we perform and watch the same action. Numerous studies have shown that people with more activity in their mirror systems seem to be better at understanding other people's emotions. Conversely, less activity in mirror systems has been linked to autism and also with psychopathy - different conditions that are both noted for low levels of empathy. Nina Bien's team at Maastricht University in the Netherlands recently identified inhibition mechanisms that hint at how we can mentally imitate an action without actually performing it (Cerebral Cortex, vol 19, p 2338). © Copyright Reed Business Information Ltd

Keyword: Vision; Autism
Link ID: 13922 - Posted: 06.24.2010

by Amy Barth Two decades ago, neurosurgeon Itzhak Fried of UCLA was stimulating a woman’s brain with electrodes that had been implanted before surgery to treat her epilepsy. He realized his patient was trying to tell him something, and as he bent down to listen, she mumbled that she had a sudden urge to shift her hand. Apparently an electrode had activated the part of the brain’s motor cortex that controlled the woman’s will to move. Fried realized that medical procedures like this one presented a rare scientific opportunity: Patients being examined for neurosurgery allow researchers to investigate the human brain in action, exploring the functions of different regions in precise detail and in real time. These days, surgeons like Fried are increasingly partnering with brain researchers to take advantage of this access. About 30 such collaborations are currently under way. Although noninvasive imaging methods such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) can track activity in the brain, they provide limited resolution. As Caltech neuroscientist Ueli Rutishauser puts it: “fMRI is like viewing a city from space. You can see the brightness of the lights and the number of inhabitants, but not what they’re doing or who is talking to whom. For that, you have to walk the streets yourself.” The visceral exploration of living brain tissue is, in many cases, still the best way to unravel cognitive functions as diverse as language, memory, vision, and movement. Many of these studies piggyback on tests run on epilepsy patients. Sometimes brain scans fail to identify which regions need to be removed to stop epileptic seizures. If so, surgeons may implant electrodes to record neural activity, then keep the patient in the hospital for days or weeks until the next seizure strikes. With the consent of these wired-up patients, Fried and Harvard Medical School neuroscientist Gabriel Kreiman are conducting studies to investigate how the brain encodes visual information.

Keyword: Brain imaging
Link ID: 13921 - Posted: 06.24.2010

by Randy O. Frost and Gail Steketee We could have found the apartment just by following the powerful musty odor that hit us as we stepped out of the elevator. When we got to the door, my guide knocked. No answer. She knocked again, then a third time. Finally, a small voice inside said, “Who’s there?” “It’s Susan, the social worker. We’re here with the cleaning crew. They’re here to clean out your apartment.” “Daniel’s not here,” the voice behind the door told us. “He went to get us breakfast.” “That’s OK. He doesn’t have to be here.” She opened the door a crack, and the door frame moved, almost imperceptibly. Yet it didn’t really move. The world seemed to shift, and I felt off balance for a moment. The door opened a bit wider, and then I saw them: cockroaches, thousands of them, scurrying along the top of the door to get out of the way. The door opened the rest of the way. The apartment was dark, and it took a moment to appreciate what was inside. No floor was visible, only a layer of dirty papers, food wrappers, and urine-stained rags. A rottweiler bolted out of the back to see what was going on. He jumped over a pile of dirty clothes—at least they looked like clothes. From the edge of the door, the massive pile of junk rose precipitously to the ceiling, like a giant sea wave. It could have been part of a landfill: papers, boxes, shopping carts, paper bags, dirty clothing, lamps—anything that could be easily collected from the street or fished out of a Dumpster. It was one solid wall of trash 20 feet deep, all the way to the back of the apartment. There must have been windows on the far wall, but they were darkened by the broken fans, boxes, and clothing covering them. Inside the condo the sweet, pungent odor of insects and rotting food enveloped us. Susan had instructed me to wear old clothes that I could throw out afterward. I was grateful for the advice but wished I’d also had a face mask—the heavy-duty kind.

Keyword: OCD - Obsessive Compulsive Disorder
Link ID: 13920 - Posted: 06.24.2010

By Matt Walker The giggling sounds of a hyena contain important information about the animal's status, say scientists. In the first study to decipher the hyena's so-called "laugh", they have shown that the pitch of the giggle reveals a hyena's age. What is more, variations in the frequency of notes used when a hyena makes a noise convey information about the animal's social rank. Details of the US-based research are published in the journal BMC Ecology. Professor Frederic Theunissen from the University of California at Berkeley, US, and Professor Nicolas Mathevon from the Universite Jean Monnet in St Etienne, France, worked with a team of researchers to study 26 captive spotted hyenas held at a field station at Berkeley. There they recorded the animals' calls in various social interactions, such as when the hyenas bickered over food, and established which elements of each call corresponded to other factors. Last year, the researchers published some provisional results from the study. Now they have confirmed that the pitch of the giggle reveals a hyena's age, while variations in the frequency of notes can encode information about dominant and subordinate status. BBC © MMX

Keyword: Animal Communication; Language
Link ID: 13919 - Posted: 06.24.2010

By Charles Q. Choi Female crayfish send mixed messages during courtship — using urine. The urine that female American signal crayfishes (Pacifastacus leniusculus) spray out triggers courtship behavior in males. The males attempt to mate only after they catch a whiff, experiments revealed, with it driving them into a sexual frenzy. However, as they unleash this seductive aphrodisiac, the females are typically fighting males, researchers found. The males actually use urine as a signal for violence, releasing it when they fight other males. The females essentially issue it as an invitation and challenge. So why send conflicting signals? By stimulating aggression in males, females can best gauge male size and strength, thereby ensuring only the fittest partners will father their offspring, scientists reason. So why use urine? "Most probably because urine provides uncheatable information," said researcher Thomas Breithaupt, a behavioral ecologist at the University of Hull in England. Animals often bluff about their prowess — male Australian slender crayfish (Cherax dispar) often bluff opponents with large claws that aren't actually stronger than normal, for instance. However, urine contains byproducts of physical processes that can serve as vital clues about their fighting power. © 2010 LiveScience.com.

Keyword: Sexual Behavior; Aggression
Link ID: 13918 - Posted: 06.24.2010

By Eric Bland Magnets can alter a person's sense of morality, according to a new report in the Proceedings of the National Academy of Sciences. Using a powerful magnetic field, scientists from MIT, Harvard University and Beth Israel Deaconess Medical Center are able to scramble the moral center of the brain, making it more difficult for people to separate innocent intentions from harmful outcomes. The research could have big implications for not only neuroscientists, but also for judges and juries. "It's one thing to 'know' that we'll find morality in the brain," said Liane Young, a scientist at MIT and co-author of the article. "It's another to 'knock out' that brain area and change people's moral judgments." Before the scientists could alter the brain's moral center, they first had to find it. Young and her colleagues used functional magnetic resonance imaging to locate an area of the brain known as the right temporo-parietal junction (RTPJ) which other studies had previously related to moral judgments. While muscle movement, language and even memory are found in the same place in each individual, the RTPJ, located behind and above the ear, resides in a slightly different location in each person. For their experiment, the scientists had 20 subjects read several dozen different stories about people with good or bad intentions that resulted in a variety of outcomes. © 2010 Discovery Communications, LLC.

Keyword: Emotions
Link ID: 13917 - Posted: 06.24.2010

by Linda Geddes AS FAR as the internet or phone networks go, bad connections are bad news. Not so in the brain, where slower connections may make people more creative. Rex Jung at the University of New Mexico in Albuquerque and his colleagues had found that creativity correlates with low levels of the chemical N-acetylaspartate, which is found in neurons and seems to promote neural health and metabolism. But neurons make up the brain's grey matter - the tissue traditionally associated with thinking power, rather than creativity. So Jung is now focusing his creativity studies on white matter, which is largely made of the fatty myelin sheaths that wrap around neurons. Less myelin means the white matter has a lower "integrity" and transmits information more slowly. Several recent studies have suggested that white matter of high integrity in the cortex, which is associated with higher mental function, means increased intelligence. But when Jung looked at the link between white matter and creativity, he found something quite different. He used diffusion tensor imaging to study the white matter of 72 volunteers. Unlike MRI, which measures tissue volume, DTI measures the direction in which water diffuses through white matter, an indication of its integrity. © Copyright Reed Business Information Ltd.

Keyword: Intelligence; Brain imaging
Link ID: 13916 - Posted: 06.24.2010

By Kristina Rehm John has a few snorts of cocaine, finds he can take it or leave it, and never bothers to take another hit. Jim has a few snorts of cocaine and before he knows it, his whole life revolves around getting more of the white powder, until his job, his marriage, his health are gone. Why? The answer may lie in one of the most exciting neuroscience discoveries of the last fifty years: the finding that new neurons are born in the adult brain. During the past decade we’ve learned a lot about the function of these newborn neurons, revealing their possible role in psychiatric and neurological diseases such as mood disorders, schizophrenia and epilepsy. The promise of this research is extraordinary. We may be on the verge of understanding, treating or even preventing life-crushing brain-based diseases — including one that affects an estimated 23 million Americans: drug and alcohol addiction. In a recent study published in the Journal of Neuroscience, Michele Noonan, a University of Texas neuroscience graduate student in the lab of Amelia Eisch, shows that a lack of neurogenesis, or birth of new neurons, in the adult rat can actually cause drug addiction. Their team blocked neurogenesis in the hippocampus — a seat of memory — with targeted irradiation, and then tested the rats for their ability to become addicted to cocaine. They found that when fewer neurons were born in the irradiated hippocampus, rats were more vulnerable to develop cocaine addiction and were more likely to relapse. This is the strongest evidence yet that there are real biological reasons why some people might be more vulnerable to addiction than others, and gives us a better understanding of the role these little newborn neurons might play in the brain. © 2010 Scientific American,

Keyword: Drug Abuse; Neurogenesis
Link ID: 13915 - Posted: 06.24.2010

by Tim Wogan If a stranger steps on your foot, you'd probably shrug your shoulders and assure him that no harm has been done, even if your toes are throbbing like crazy. But if that stranger instead takes a swing with his fist-successfully or not—most people are unlikely to be so forgiving. Researchers now believe they've demonstrated which part of the brain allows us to make moral judgments of another person's motives, a find that could lead to a greater understanding of Asperger syndrome and other autism spectrum disorders. Scientists already have some clues about how we judge the actions of another person. Previous research using functional magnetic resonance imaging, a method of imaging activity in the brain, has shown that an area just above the right ear called the right temporoparietal junction (RTPJ) receives more blood than usual when we read about people’s beliefs and intentions, particularly if we use the information to judge people negatively. But it's not possible to say from a simple observational study whether the brain activity is actually necessary to make such a judgment or whether making the negative judgment causes this region to become more active. So social neuroscientist Liane Young of the Massachusetts Institute of Technology in Cambridge and colleagues decided to turn off the right temporoparietal junction and see whether people would make different judgments of others' actions. They achieved this using transcranial magnetic stimulation (TMS), a technology that uses a tightly focused magnetic field to temporarily disable individual regions of the brain. © 2010 American Association for the Advancement of Science

Keyword: Attention; Autism
Link ID: 13914 - Posted: 06.24.2010