by Rajendrani Mukhopadhyay Is that Folgers coffee in your cup or Maxwell House? Now you no longer have to rely on your nose to tell. Researchers have developed an analyzer that can distinguish between 10 commercial brands of coffee and can even tell apart coffee beans roasted at various temperatures for different times. The advance could help growers determine within minutes whether a particular batch of coffee is just as good as the previous one or whether it's undrinkable. Researchers have been trying for years to come up with a simple way to analyze coffee. But it's no easy task. The challenge is that the aroma of roasted coffee beans consists of more than 1000 compounds that change with roasting temperatures and time. Traditional methods of chemical analysis like gas chromatography combined with mass spectrometry generally have difficulty distinguishing between compounds that are very similar to one another. And "electronic noses," an array of dyes, and other sensors that change color or chemical properties when they react with certain molecules suffer from the same drawback. Over the past decade, chemist Kenneth Suslick and colleagues at the University of Illinois, Urbana-Champaign, have refined the electronic nose approach. In the new study, they used dyes that interact strongly with other chemicals, making them more specific. They then put drops of 36 dyes on a polymer film the size of a nickel. The pigments in the dyes belonged to a range of chemical classes, including metalloporphyrins (a class of molecules which give blood and chlorophyll their distinctive colors); pH indicators; and molecules that change color with certain chemical vapors. © 2010 American Association for the Advancement of Science

Keyword: Chemical Senses (Smell & Taste); Robotics
Link ID: 13781 - Posted: 06.24.2010

Liz Else, associate editor Challenging a multibillion-dollar global industry is bound to be an uncomfortable mission, all the more so if you risk being accused of promoting suffering, being a denialist, or even of culpable ignorance. Few writers who take on the mental health industry can be doing it for the money or in the hopes of sales matching Peter Kramer's 1990s hit Listening to Prozac. It was Kramer who coined the phrase "cosmetic psychopharmacology" to describe a not-too-distant utopia in which drugs such as the selective serotonin reuptake inhibitor Prozac, normally used to treat depression, would be used to enhance or change personality. Kramer did warn of the drug's downsides (tremors, loss of libido, suicidal ideation), but the prospect of exchanging shyness, timidity and other social dysfunctions for self-assurance, gregariousness and success ensured the book's popularity. Fast-forward to 2010 and optimism about biochemical aids in the endless pursuit of happiness or as fixes for misery seems to be vanishing like the morning mist. Writers continue to take the mental health industry apart, big genetics still fails to nail "genes for" mental illness in any important sense, and the deadline for a new edition of the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders has slipped a year amid ugly rows and claims that tens of millions of dollars could be spent on unnecessary drugs should new diseases with no clear scientific foundation be included in the DSM. © Copyright Reed Business Information Ltd.

Keyword: Depression
Link ID: 13780 - Posted: 06.24.2010

By Cristen Conger Chronic insomniacs losing out on sleep may also be missing brain matter. For the first time, brain imaging has linked chronic insomnia to lower gray matter density in areas that regulate the brain's ability to make decisions and to rest. The research could lead to new treatment plans for people who struggle with sleeplessness. "The findings predict that chronic insomnia sufferers may have compromised capacities to evaluate the affective value of stimuli," said Ellemarijie Altena, lead author of the study from the Netherlands Institute for Neuroscience. "This could have consequences for other cognitive processes, notably decision-making." The study, published in Biological Psychiatry, compared the white and gray matter volumes of 24 older, chronic insomnia patients to 13 normal sleepers, and controlled for physical and psychiatric disorders that could also alter brain densities. Severe insomniacs exhibited the most extensive density loss, regardless of how long they had suffered from the disorder. However, the researchers are not yet able to pin down whether sleeplessness precedes gray matter loss or the other way around. © 2010 Discovery Communications, LLC

Keyword: Sleep; Brain imaging
Link ID: 13779 - Posted: 06.24.2010

by Ewen Callaway A GENE variant that ups your risk of developing Alzheimer's disease in old age may not be all bad. It seems that young people with the variant tend to be smarter, more educated and have better memories than their peers. The discovery may improve the variant's negative image (see "Yes or no"). It also suggests why the variant is common despite its debilitating effects in old age. Carriers of the variant may have an advantage earlier in life, allowing them to reproduce and pass on the variant before its negative effects kick in. "From an evolutionary perspective it makes sense," says Duke Han at Rush University Medical Center in Chicago. The "allele" in question is epsilon 4, a version of the apolipoprotein E gene (APOE). Having one copy increases the risk of developing Alzheimer's at least fourfold compared with people who have other forms of the gene. A person with two copies has up to 20 times the risk. One big clue that epsilon 4 might be beneficial emerged several years ago, when Han's team scanned the APOE genes of 78 American soldiers. All had suffered traumatic brain injuries, many while serving in Iraq. Sixteen had at least one copy of epsilon 4. Han's team expected to find that these carriers would be in worse cognitive shape than their counterparts with different versions of APOE, given previous studies that showed elderly people with epsilon 4 fare worse after head injury. But the opposite was true: soldiers with the epsilon 4 allele had better memory and attention spans (Journal of Neurology, Neurosurgery & Psychiatry, DOI: 10.1136/jnnp.2006.108183). © Copyright Reed Business Information Ltd

Keyword: Alzheimers; Learning & Memory
Link ID: 13778 - Posted: 06.24.2010

Andy Coghlan, reporter Remember Rom Houben, the man thought to be in a vegetative state, who turned out to have been fully conscious and "locked in" for more than 20 years? It has now emerged that doubts that he was really communicating using residual movement in his finger and a touchscreen were spot on. "Powerlessness. Utter powerlessness. At first I was angry, then I learned to live with it." That's what Houben, brain damaged in a car accident in 1983, apparently told the world by communicating via a computer touch-screen, at least according to the original report of Houben's story in Der Spiegel in November 2009. The story attracted huge media attention, which quickly turned sour when several videos of Houben typing at the screen prompted commentators to cry foul. They pointed out that the speed of the typing, and the fact that Houben is not even looking at the keyboard at various points in the footage, suggested it was in fact the person holding his finger who was behind the messages. Now, according to a follow-up article in Der Spiegel, it seems these suspicions have been borne out. The magazine reports that Steven Laureys of the University of Liège in Belgium, who first diagnosed Houben as conscious, but dissociated himself from the communication fiasco, has carried out subsequent tests to see if Houben is capable of this kind of communication. He concludes that the speech therapist holding Houben's finger was in fact the source of the messages. © Copyright Reed Business Information Ltd.

Keyword: Attention
Link ID: 13777 - Posted: 06.24.2010

WASHINGTON - A hormone thought to encourage bonding between mothers and their babies may foster social behavior in some adults with autism, French researchers said on Monday. They found patients who inhaled the hormone oxytocin paid more attention to expressions when looking at pictures of faces and were more likely to understand social cues in a game simulation, the researchers said in the journal Proceedings of the National Academy of Sciences. Angela Sirigu of the Center of Cognitive Neuroscience in Lyon, who led the study, said the hormone has a therapeutic potential in adults as well as in children with autism. "For instance, if oxytocin is administered early when the diagnosis is made, we can perhaps change very early the impaired social development of autistic patients," Sirigu said in an email. Sirigu said the study focused on oxytocin because it was known to help breast-feeding mothers bond with their infants and because earlier research has shown that some children with autism have low levels of the hormone. People with Asperger's syndrome and other autism spectrum disorders often have problems with social interaction. Sirigu said oxytocin could help autism patients who have normal intellectual functions and fairly good language abilities because it improves eye contact. Copyright 2010 Reuters

Keyword: Autism; Hormones & Behavior
Link ID: 13776 - Posted: 06.24.2010

By Sandra G. Boodman Karen Hammerman could see that her son was upset, and when he told her why, she was unnerved. Adam Hammerman, then a 16-year-old sophomore at Charles E. Smith Jewish Day School in Montgomery County, had missed a week of school because of a virus and telephoned several classmates to see what assignments he'd missed. "Something's wrong," he told his mother last May. "All my friends are mad at me. They say I've called them five times already and they're not going to tell me again." But Adam had no memory of making the calls. The incident, Karen Hammerman soon discovered, was not isolated. One morning as Adam prepared to take a shower, he screamed after seeing himself in the mirror: He said he did not remember getting a haircut the previous day. He called his mother from school to ask what time she was picking him up, then called again five minutes later to ask the same thing. "Basically it was like living with a 16-year-old Alzheimer's patient," Karen Hammerman recalled. Despite numerous tests, nearly a dozen doctors in Washington and Baltimore could find no reason for Adam's sudden and profound memory loss. "They would either tell me, 'I've never seen anything like this,' or else that he's making it up," his mother recalled. One neurologist's assistant castigated Hammerman for insisting on expensive tests for a problem that was clearly psychological. © 2010 The Washington Post Company

Keyword: Learning & Memory
Link ID: 13775 - Posted: 06.24.2010

By LAURA BEIL HOUSTON — One callous question turned Brittany Caesar into a medical pioneer: “Why do you eat so much? It’s not normal.” At that moment, she was in the Campbell Middle School cafeteria, sitting down to her usual lunch: two cheeseburgers, two orders of fries and a Coke. She knew she weighed too much. Her whole family weighed too much. But her world revolved around food, and she could not imagine any other existence. “Food was my best friend,” she said. “It was always there for me.” Somehow, her classmate’s taunt, back in 2003, wounded her in a way the usual fat jokes never had. She fled to the bathroom and wept, vowing to lose weight. Her salvation did not arrive until more than a year later when, at age 14, doctors at Texas Children’s Hospital performed a gastric bypass that left her stomach the size of an egg. On the day of surgery, she weighed 404 pounds. Ms. Caesar, now 20 years old and 175 pounds, was the first teenager to undergo a gastric bypass at Texas Children’s, but more quickly followed. Today, it maintains one of the busiest bariatric practices for adolescents in the country, performing one or two bypasses each month. Although the procedure is still considered experimental for children, it is fast becoming the next front in the battle against pediatric obesity. “I honestly believe that in 5 to 10 years you’ll see as many children getting weight-loss procedures as adults,” said Dr. Evan Nadler, co-director of the Obesity Institute at Children’s National Medical Center in Washington. Copyright 2010 The New York Times Company

Keyword: Obesity; Development of the Brain
Link ID: 13774 - Posted: 06.24.2010

A gene that may give you an increased risk of a distressing early form of dementia has been identified by Cambridge scientists. Fronto-temporal dementia (FTD) is the second most common type of dementia in the under 65s and can result in a complete personality change. The researchers studied the brains of 515 people with FTD and found the gene on chromosome 7. A charity said this could open the door to new treatments for the disease. Writing in the journal Nature, Professor Maria Grazia Spillantini, of the University of Cambridge, said her team had established an international collaboration with investigators in 11 countries including the UK, the US, Belgium and Spain. The Cambridge team compared the brains of 515 people with known FTD with 2,509 brains of people without the condition. They found several different mutations on chromosome 7 which are thought to affect around half of the people with FTD. These mutations increase the amounts of the protein the gene codes for. About 20% of individuals with FTD have another kind of genetic mutation known as a GRN mutation. Professor Spillantini thinks that the new gene accelerates the harm caused by the GRN mutation and makes the disease progress faster: "We found a specific gene that was associated with an increased risk of the disease. "A better understanding of how the gene is involved could identify a new approach to tackle this disease." (C)BBC

Keyword: Alzheimers; Genes & Behavior
Link ID: 13773 - Posted: 02.15.2010

Jennifer S. Altman A stand-up comedian, a ventriloquist who performs for children and a high school sophomore are among the people who share their stories about living with Tourette’s syndrome in the latest installment of Patient Voices. The often misunderstood condition can cause a range of tics, including sudden jerking movements, grunting, snorting and clearing the throat, which typically first appear during childhood. This week, Dr. Robert A. King and Dr. James F. Leckman of the Yale School of Medicine join the Consults blog to answer readers’ questions about Tourette’s syndrome. “Once thought to be a rare, severe and lifelong condition, Tourette’s is now known to be relatively common, affecting up to one percent of school-age children,” Dr. King says. “Symptoms are often mild and can spontaneously, and markedly, improve by later adolescence.” Dr. King is professor of child psychiatry and medical director of the Yale Child Study Center’s Tourette’s/Obessive-Compulsive Disorder Clinic. Dr. Leckman is the Neison Harris Professor of Child Psychiatry and Pediatrics at Yale, where he also serves as the center’s director of research. Both doctors have been intensively involved in the clinical care of individuals with Tourette’s syndrome and early onset obsessive-compulsive disorder for more than two decades. Do you have a question about Tourette’s syndrome? Post your comments and questions in the comments box below. Drs. King and Leckman will be responding to readers next week. Copyright 2010 The New York Times Company

Keyword: Tourettes
Link ID: 13772 - Posted: 06.24.2010

BY ERIC FERRERI, Staff Writer Kevin LaBar needed to provoke emotional highs in his research subjects. So the Duke neuroscientist turned to what else? A Duke/UNC basketball game. The result: a paper in an academic journal peeling back the cover on the brain's tendency to recall happy moments better than disappointing ones. LaBar and his research team took two dozen college-age men - half Duke fans, half UNC fans - and had them watch a Duke/UNC game from Feb. 3, 2000, a nail-biter at the Dean Smith Center that Duke pulled out 90-86 in overtime. "The question is, how do you ethically manipulate people's emotions to the extreme?" LaBar said. "A Duke/UNC rivalry is rife with emotion." The research subjects - who first had to prove their fan cred by filling out a college hoops questionnaire - watched the game three times in the course of the week. Then, they were put into an MRI machine and shown clips from the game that stopped just before the ball reached the hoop. The subjects were then quizzed on whether the shots went in or not. The conclusion: The UNC fans remembered more of the big shots the Tar Heels made. The Duke fans remembered more of the Blue Devil highlights. The explanation: A big, emotional moment in a game triggers a higher level of brain processing. Essentially, the brain works harder when something good happens. "It's like for the spectacular shot, you sort of put yourself in the shoes of the player," LaBar said. "And if your team isn't doing well, you kind of tune it out." © Copyright 2010, The News & Observer Publishing Company,

Keyword: Emotions; Learning & Memory
Link ID: 13771 - Posted: 06.24.2010

Delays at crucial points during the development of the brain in the womb may explain why people with a condition linked to autism do not like hugs. A study in mice with fragile X syndrome found wiring in the part of the brain that responds to touch is formed late. The findings may help explain why people with the condition are hypersensitive to physical contact, the researchers wrote in Neuron. It also points to key stages when treatment could be most effective. Fragile X syndrome is caused by a mutant gene in the X chromosome that interferes in the production of a protein called fragile X mental retardation protein (FMRP). Under normal circumstances, the protein directs the formation of other proteins that build synapses in the brain. Boys are usually more severely affected with the condition - which is the leading known cause of autism - because they have only one X chromosome. In addition to mental impairment, hyperactivity, emotional and behavioural problems, anxiety and mood swings, people with fragile X also show what doctors call "tactile defensiveness", which means they do not make eye contact and do not like physical contact and are hypersensitive to touch and sound. By recording electrical signals in the brains of mice, bred to mimic the condition, the researchers found that connections in the sensory cortex in the brain were late to mature. This "mistiming" may trigger a domino effect and cause further problems with the correct wiring of the brain, they concluded. The study also found these changes in the brain's connections occur much earlier than previously thought, midway through a baby's development in the womb. (C)BBC

Keyword: Autism; Genes & Behavior
Link ID: 13770 - Posted: 02.13.2010

Maybe everyone could use a gay uncle. A new study found that homosexual men may be predisposed to nurture their nieces and nephews as a way of helping to ensure their own genes get passed down to the next generation. Research has confirmed that male homosexuality is at least partly hereditary – it tends to cluster in families, and identical twin brothers of gay men are more likely to be gay than fraternal twin brothers, who do not share identical DNA. But scientists have been puzzled about how these genes are perpetuated, since homosexual males are less likely to reproduce than straight males. Basically, why haven't gay people gone extinct? One idea is called the "kin selection hypothesis." Perhaps gay men are biologically predisposed to help raise the offspring of their siblings and other relatives. "Maybe what's happening is they're helping their kin reproduce more by just being altruistic towards kin," said evolutionary psychologist Paul Vasey of the University of Lethbridge in Canada. "Kin therefore pass on more of the genes which they would share with their homosexual relatives." Vasey and his student Doug VanderLaan tested this hypothesis among a group of men called fa'afafine on the Pacific island of Samoa. Fa'afafine are effeminate men who are exclusively attracted to men as sexual partners, and are generally recognized and tolerated as a distinct gender category — neither male nor female. © 2010 LiveScience.com.

Keyword: Sexual Behavior; Evolution
Link ID: 13769 - Posted: 06.24.2010

By Adam Hadhazy As Olympians go for the gold in Vancouver, even the steeliest are likely to experience that familiar feeling of "butterflies" in the stomach. Underlying this sensation is an often-overlooked network of neurons lining our guts that is so extensive some scientists have nicknamed it our "second brain". A deeper understanding of this mass of neural tissue, filled with important neurotransmitters, is revealing that it does much more than merely handle digestion or inflict the occasional nervous pang. The little brain in our innards, in connection with the big one in our skulls, partly determines our mental state and plays key roles in certain diseases throughout the body. Although its influence is far-reaching, the second brain is not the seat of any conscious thoughts or decision-making. "The second brain doesn't help with the great thought processes…religion, philosophy and poetry is left to the brain in the head," says Michael Gershon, chairman of the Department of Anatomy and Cell Biology at New York–Presbyterian Hospital/Columbia University Medical Center, an expert in the nascent field of neurogastroenterology and author of the 1998 book The Second Brain (HarperCollins). Technically known as the enteric nervous system, the second brain consists of sheaths of neurons embedded in the walls of the long tube of our gut, or alimentary canal, which measures about nine meters end to end from the esophagus to the anus. The second brain contains some 100 million neurons, more than in either the spinal cord or the peripheral nervous system, Gershon says. © 2010 Scientific American

Keyword: Emotions
Link ID: 13768 - Posted: 06.24.2010

by Anil Ananthaswamy A SIGN of a cell's age could help predict the onset of dementia. Elderly people are more likely to develop cognitive problems if their telomeres - the stretches of DNA that cap the ends of chromosomes - are shorter than those of their peers. The shortening of telomeres is linked to reduced lifespan, heart disease and osteoarthritis. Telomeres naturally shorten with age as cells divide, but also contract when cells experience oxidative damage linked to metabolism. Such damage is associated with cognitive problems like dementia. Thomas von Zglinicki at Newcastle University, UK, showed in 2000 that people with dementia not caused by Alzheimer's tended to have shorter telomeres than people without dementia. To see if healthy individuals with short telomeres are at risk of developing dementia, Kristine Yaffe at the University of California, San Francisco, and colleagues, followed 2734 physically fit adults with an average age of 74. Yaffe's team tracked them for seven years and periodically assessed memory, language, concentration, attention, motor and other skills. At the start, the researchers measured the length of telomeres in blood cells and grouped each person according to short, medium or long telomeres. After accounting for differences in age, race, sex and education, the researchers found that those with long telomeres experienced less cognitive decline compared to those with short or medium-length telomeres (Neurobiology of Aging, DOI: 10.1016/j.neurobiolaging.2009.12.006). © Copyright Reed Business Information Ltd

Keyword: Alzheimers; Genes & Behavior
Link ID: 13767 - Posted: 06.24.2010

By Melinda Wenner Americans take more antidepressants than they do any other type of prescription drug, and pregnant women are no exception. One out of every eight pregnant women in the U.S. takes selective serotonin re­up­take inhibitors (SSRIs) to treat depression or other mood disorders. A handful of recent studies suggest that these drugs could have adverse effects on infant health: they may increase the risk for rare heart defects, premature delivery, low birth weight and withdrawal symptoms. Nevertheless, some doctors argue that the benefits these drugs provide still outweigh the potential risks. Worries over the use of SSRIs during pregnancy first surfaced in journal articles published in the 1980s, but it was not until 2005 that the U.S. Food and Drug Administration conceded that babies born of mothers who take paroxetine (sold as Paxil and Seroxa) during their first trimester are up to twice as likely to exhibit fetal heart defects. A 2005 study published in the Lancet also found that some newborns born of mothers taking paroxetine suffer from withdrawal symptoms such as convulsions and abnormal crying for several days. More recently, pregnancy risks associated with other SSRIs have also come to light. A study published in the September 26 issue of the British Medical Journal monitored nearly 500,000 Danish children from nationwide registries and found that women who take sertraline (Zoloft), citalopram (Celexa) and fluoxetine (Prozac) are more likely to give birth to babies with heart defects, although the overall risk is still quite low. A study in press in the Journal of Clinical Psychopharmacology notes that women treated with SSRIs during late pregnancy are more likely to give birth to small and premature babies. © 2010 Scientific American,

Keyword: Depression
Link ID: 13766 - Posted: 06.24.2010

More than 55% of multiple sclerosis patients have been found to have constricted blood vessels in their brains, a US study says. The preliminary results are from the first 500 patients enrolled in a trial at the University of Buffalo. The abnormality was found in 56.4% of MS patients and also in 22.4% of healthy controls. The MS Society said it was intriguing but not proof that this caused MS - as one leading expert claims. The New York researchers were testing a theory from Italian researcher, Dr Paolo Zamboni who claims that 90% of MS is caused by narrowed veins. He says the restricted vessels prevent the blood from draining fast enough and injure the brain by causing a build up of iron which leads to MS. He has already widened the blockages in a handful of patients including his wife. MS is a long-term inflammatory condition of the central nervous system which affects the transfer of messages from the nervous system to the rest of the body. The Buffalo team used Doppler ultrasound to scan the patients in different body postures to view the direction of venous blood flow. The 500 MS patients, both adults and children, also underwent MRI scans of the brain to measure iron deposits in surrounding areas of the brain. The full results will be presented at an American neurology conference in April. There were 161 healthy controls. Robert Zivadinov who led the study at the University of Buffalo, said he was "cautiously optimistic and excited" about the preliminary data. "They show that narrowing of the extracranial veins, at the very least, is an important association in multiple sclerosis. We will know more when the MRI and other data collected in this study are available." (C)BBC

Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 13765 - Posted: 02.11.2010

Characterized by sudden jerking movements and uncontrollable tics and vocalizations, Tourette’s syndrome is a strange, often misunderstood condition. What is it like to live without full control of your body? Seven men and women talk about living with the twitches of Tourette’s. What is it like to live with a chronic disease, mental illness or confusing condition? In Patient Voices, we feature first person accounts of the challenges patients face as they cope with various health issues. Interactive Feature Patient Voices: Migraine Almost 30 million Americans suffer from migraines. What is it like to live with migraine pain? Six men and women speak about their experiences. Copyright 2010 The New York Times Company

Keyword: Tourettes
Link ID: 13764 - Posted: 06.24.2010

Last week, the British medical journal the Lancet, which had originally published a controversial 1998 study by British researcher Andrew Wakefield that implied a link between autism and the vaccine for measles, mumps and rubella, formally retracted that study. In the wake of this, one of the tantalizing areas to be explored is the role diet might play in the lives of children with autism. Research published in October showed that 1 in 91 children has a disorder somewhere along the autism spectrum, with degrees of severity ranging from mild to major. (Federal figures released in December put that number at 1 in 110.) For now, the only treatment known to help kids with autism -- the most common of the conditions that make up what is known as autism spectrum disorder (ASD) -- is placement in an education program that's appropriate to their specific needs, providing speech and language therapy to boost their ability to communicate, and helping them develop social skills, according to Susan Levy, director of the Regional Autism Center at the Children's Hospital of Philadelphia and a member of the American Academy of Pediatrics' autism subcommittee. But legions of worried and desperate parents and even some physicians have put stock in other remedies, many of them food-related. Some have believed there's a connection between autism and gastrointestinal problems, which was first suggested in the discredited 1998 paper. "The presumed mechanism of action was that people with autism have a leaky gut, which led to abnormal absorption of some of the breakdown products of gluten and casein," Levy explains. That abnormality, in the leaky-gut theory, would allow those byproducts to be absorbed into the bloodstream and somehow cross into the brain. © 2010 The Washington Post Company

Keyword: Autism
Link ID: 13763 - Posted: 06.24.2010

By Katie Moisse Imagine you've lost your job. You have some money saved, and a chance to double it with a gamble. But if you lose the bet, you'll forfeit everything. What would you do? Most people would not gamble their savings, according to Benedetto De Martino of California Institute of Technology, author of a study published February 8 in Proceedings of the National Academy of Science. People tend to choose avoiding losses over acquiring gains—a behavior known as loss-aversion. But people with damage to the amygdala—an almond-shaped part of the brain involved in emotion and decision-making—are more likely to take bigger risks with smaller potential gains, De Martino's study found. Two women with bilateral amygdala damage showed a dramatic reduction in loss aversion compared with age-matched control subjects on a series of experimental gambles, despite understanding full well the values and risks involved. De Martino already suspected that the amygdala was crucial for loss-aversion based on earlier studies using functional magnetic resonance imaging (fMRI). But these two rare cases with damage to the very structure in question allowed De Martino to directly test his hypothesis. "In functional MRI, you never know if the response is reflecting something else. With the amygdala injury, you have an on "off" response," De Martino says. © 2010 Scientific American

Keyword: Emotions; Drug Abuse
Link ID: 13762 - Posted: 06.24.2010