By Siri Carpenter Lousy day? Don’t try to think happy thoughts—just think fast. A new study shows that accelerated thinking can improve your mood. In six experiments, researchers at Princeton and Harvard universities made research participants think quickly by having them generate as many problem-solving ideas (even bad ones) as possible in 10 minutes, read a series of ideas on a computer screen at a brisk pace or watch an I Love Lucy video clip on fast-forward. Other participants performed similar tasks at a relaxed speed. Results suggested that thinking fast made participants feel more elated, creative and, to a lesser degree, energetic and powerful. Activities that promote fast thinking, then, such as whip­ping through an easy crossword puzzle or brain-storming quickly about an idea, can boost energy and mood, says psychologist Emily Pronin, the study’s lead author. Pronin notes that rapid-fire thinking can sometimes have negative consequences. For people with bipolar disorder, thoughts can race so quickly that the manic feeling becomes aversive. And based on their own and others’ research, Pronin and a colleague propose in another recent article that although fast and varied thinking causes elation, fast but repetitive thoughts can instead trigger anxiety. (They further suggest that slow, varied thinking leads to the kind of calm, peaceful happiness associated with mindfulness meditation, whereas slow, repetitive thinking tends to sap energy and spur depressive thoughts.) © 1996-2009 Scientific American Inc.

Keyword: Emotions; Attention
Link ID: 12523 - Posted: 06.24.2010

By Coco Ballantyne A new study in mice suggests that a mother's childhood experiences may affect the brain function of her offspring. Researchers found that mouse moms who were physically active, stimulated and changed their living arrangements frequently as youngsters gave birth to babies with better memory than those born to mothers raised in dull environments. "How well mice remember when they are young is influenced by exposures to stimuli of their mothers when they were young," says Larry Feig, a biochemist at Tufts University Medical School in Boston and senior author of the study that will published tomorrow in The Journal of Neuroscience. This study adds to an accumulating body of evidence that not all the physiological characteristics passed from parents to offspring are genetic, Feig notes. Is it possible the same is true in humans? "The best we could say is if this occurs in humans," he says, "it would suggest that experiences [your mother] had during adolescence could influence your memory." Feig's team previously showed that stimulating environments trigger a biochemical cascade in mice that enhances their recall by fostering communication between nerve cells in the hippocampus, a region of the brain that controls memories. © 1996-2009 Scientific American Inc.

Keyword: Development of the Brain; Learning & Memory
Link ID: 12522 - Posted: 06.24.2010

By Katey Rich One Of History's Most Famous Brains Goes To The Movies Henry Molaison never knew throughout his long life that he was making an irreplaceable contribution to neuroscience. And now after his death there will be a movie to commemorate it. Columbia Pictures and Scott Rudin have picked up the rights to a forthcoming memoir about Molaison, who was known for the 45 years that Dr. Suzanne Corkin studied him only as H.M. Molaison, after suffering seizures since a boyhood bicycle accident, had a lobotomy at age 27 that ended the seizures, but also made him completely unable to form new memories. As described in his New York Times obituary, Molaison would not remember the scientists who worked with him from day to day, but with time could improve at tasks they taught him, proof that there was some innate memory that remained in him after all. Variety says Columbia has also picked up the rights to another book about Molaison, and plans to tell the story through Corkin's point-of-view. Given how well-read the Times obituary was, it seems maybe this is a neuroscience milestone that will have an appeal outside beyond the medical community.

Keyword: Learning & Memory
Link ID: 12521 - Posted: 02.05.2009

By Paul Raeburn When my wife, Elizabeth, was pregnant, she had a routine ultrasound exam, and I was astonished by the images. The baby’s ears, his tiny lips, the lenses of his eyes and even the feathery, fluttering valves in his heart were as crisp and clear as the muscles and tendons in a Leonardo da Vinci drawing. Months before he was born, we were already squabbling about whom he looked like. Mostly, though, we were relieved; everything seemed to be fine. Elizabeth was 40, and we knew about all the things that can go wrong in the children of older mothers. We worried about Down syndrome, which is more common in the offspring of older women. Elizabeth had the tests to rule out Down syndrome and a few other genetic abnormalities. That was no guarantee the baby would be okay, but the results were reassuring to us. The day after Henry was born, while we were still bleary-eyed from a late-night cesarean delivery, we caught part of a report on the hospital television about an increased risk of autism in the children of older fathers. Until then, all we’d thought about was Elizabeth’s age—not mine. We’d had no idea that my age could be an important factor in our baby’s health. When we got home, I looked up the study. Researchers had analyzed medical records in Israel, where all young men and most women must report to the draft board for mandatory medical, intelligence and psychiatric screening. They found that children born to fathers 40 or older had nearly a sixfold increase in the risk of autism as compared with kids whose fathers were younger than 30. Children of fathers older than 50—that includes me—had a ninefold risk of autism. © 1996-2009 Scientific American Inc.

Keyword: Autism; Schizophrenia
Link ID: 12520 - Posted: 06.24.2010

Some children with a common mental disorder may have newly identified genetic mutations that affect learning and memory. In Thursday's issue of the New England Journal of Medicine, Dr. Jacques Michaud, a geneticist at the Sainte-Justine University Hospital Research Center in Montreal, and an international team of colleagues said they've identified mutations for non-syndromic mental deficiency or NSMD. Children with the mutations look normal physically but may have delays in language and mental development and, in some cases, a mild form of epilepsy. The researchers discovered that three per cent of the 94 subjects with NSMD they studied had harmful mutations in the SYNGAP1 gene. "Several observations indicate that new mutations are a frequent cause of neurodevelopmental disorders, but their identification has been difficult because it requires the study of a large fraction of genes, which represents a challenging task," said Dr. Fadi Hamdan, an author of the study. To identify the mutations, the researchers used a new technology to study hundreds of genes in people with NSMD, and 142 subjects with autism spectrum disorders, 143 subjects with schizophrenia, and 190 control subjects. © CBC 2009

Keyword: Development of the Brain; Genes & Behavior
Link ID: 12519 - Posted: 06.24.2010

By Susan Milius Maybe female seed beetles have their own what-the-bleep exclamation. Even for insects, it’s difficult to imagine any other reaction to a male Callosobruchus maculatus beetle’s sex organ, which has spikes. “It jumps to mind as something quite dumb,” says Göran Arnqvist, an evolutionary biologist at Uppsala University in Sweden, who for much of the past eight years has studied seed beetle sex. Male beetles of several Callosobruchus species have sharp edges on their sperm-delivery organs. The females’ ducts grow a bit of extra toughening but not enough to make sex safe from the risk of injury. After many tests, Arnqvist has concluded that the genital excesses aren’t good for the species as a whole. These seed beetles would have less-damaging sex — and would produce more babies — if males lost their edges. Discussions of evolution often glorify the beautifully apt forms: orchids with nectar recesses just the right length for the tonguelike structure of a certain moth, or harmless butterflies with the same wing colors as a poisonous neighbor. Yet the most dramatic examples of the power of evolutionary theory may come from the strange and ugly stuff — biology that seems too dumb to have been designed. Trying to understand counterintuitive sexual parts and habits follows in the best of scientific traditions. As Charles Darwin worked on evolution, he pondered male phenomena that looked useless, or even harmful, for surviving. Outsized horns on male beetles puzzled him, as did male birds with gorgeous plumage. © Society for Science & the Public 2000 - 2009

Keyword: Sexual Behavior; Evolution
Link ID: 12518 - Posted: 06.24.2010

By Sandra G. Boodman Valerie Novak fervently wished doctors would stop telling her the intense headache she'd endured for several weeks was a migraine. For one thing, neither the Georgetown University senior nor her close relatives had headaches, and migraines are frequently familial. None of the increasingly potent drugs doctors prescribed was doing much good. And the 22-year-old had lost 15 pounds in three weeks from bouts of severe vomiting. "I was so frustrated and upset," recalled Novak of her ordeal last summer, which involved consultations with half a dozen doctors, several trips to area emergency rooms and two hospitalizations. Novak, who had always been healthy, said she feared the unrelenting pain in her left temple and associated symptoms were something "I'd have to live with for the rest of my life." Her mother, Kathy Novak, a nurse practitioner in Bowie, was similarly skeptical of the diagnosis but grateful that doctors had ruled out more ominous possibilities, such as a brain tumor. When her middle daughter began complaining about double vision, Kathy took her to an ophthalmologist. His judgment led to an accurate diagnosis that had nothing to do with migraines but was instead a rare complication of a common item listed on Novak's medical records. Left untreated, it might have killed her. An Arabic studies major who had been scheduled to graduate in December 2008, Novak said her headache began last summer while she was in Colorado visiting her boyfriend. When over-the-counter pain relievers failed to work, she consulted a Denver physician, who told her she probably had a migraine that would go away on its own. © 2009 The Washington Post Company

Keyword: Pain & Touch; Hormones & Behavior
Link ID: 12517 - Posted: 06.24.2010

New ways of treating Parkinson's disease by stimulating the brain are to be investigated by scientists. Deep brain stimulation eases symptoms, such as tremors, by allowing sufferers to deliver electrical pulses to electrodes implanted in their brains. Researchers at St Andrews University will study what happens in the head when the electrodes are switched on. They will also look at whether other symptoms can be eased by targeting different parts of the brain. Symptoms of Parkinson's disease include tremors, difficulty moving and poor balance. Professor Philip Winn, from St Andrews University, will work with researchers in Germany, Italy, France and Scotland on the three-year, £1.17m project. He said he wanted to find answers to a range of questions. "One is to do with exactly what effect the electrical stimulation is having on the brain. Is it the case that we're stimulating activity or is it in fact the case that the stimulation we do, what the electrical pulses do, is actually to shut down activity locally where the electrode is implanted?" Prof Winn said. He said more effective treatment for Parkinson's could be developed if they could understand the effect of the stimulation. The other part of the research will consider where in the brain the electrodes should be placed. Prof Winn said: "If you put the electrode at the most commonly used site you can inhibit tremors that Parkinsonian patients have, which are very disturbing and distressing to them. "But it's thought possible that if we put electrodes at other sites we can have an affect on the posture and gait problems that patients have. (C)BBC

Keyword: Parkinsons
Link ID: 12516 - Posted: 02.03.2009

Tracking changes in the levels of a certain hormone during pregnancy may help to predict which women may suffer postpartum depression, a small study suggests. Risk factors include a history of depression, a stressful or anxious pregnancy, a lack of social support, and low self-esteem, but these explain only a portion of why some women develop postpartum depression. In Monday's online issue of Archives of General Psychiatry, researchers who studied 100 women said they found 12 out of 16 participants who had postpartum depression also had high levels of corticotropin-releasing hormone or CRH. In the study, high levels of CRH at 25 weeks gestational age helped to predict future postpartum depression or PPD in about three-fourths of women and misclassified 24 per cent, the researchers said. CRH is normally produced in tiny amounts by the brain's hypothalamus in response to stress. During pregnancy, the placenta produces much more of the hormone, which is thought to prepare a woman's body for childbirth. Levels of CRH and other hormones drop after giving birth. © CBC 2009

Keyword: Depression; Hormones & Behavior
Link ID: 12515 - Posted: 06.24.2010

Peter Aldhous, San Francisco bureau chief Among my editors in London, I'm sometimes known as the Prince of Darkness - not for any particular satanic tendencies, but because I frequently send emails when most people in my time zone in California are fast asleep. Like millions of others, I'm a chronic insomniac, so when the table of contents for the latest issue of Behavior Therapy dropped into my email inbox at 1:45 am on Sunday, I was drawn to a paper entitled Sleep Hygiene Practices of Good and Poor Sleepers in the United States: an Internet-Based Study. For the uninitiated, "sleep hygiene" has nothing to do with the cleanliness of your bedroom, but instead refers to behaviours that influence the quality of your sleep. The problem is that previous research has yielded conflicting results as to which behaviours, exactly, are the most disruptive. To further investigate the issue, Les Gellis of the Philadelphia Veterans Medical Center and Kenneth Lichstein of the University of Alabama in Tuscaloosa conducted an online survey of 128 "good" and 92 "poor" sleepers - the latter scoring 7 or more on a 21-point scale called the Pittsburgh Sleep Quality Index. You can rate yourself on the index here (pdf format) - my score was 12. Surprisingly, there was little difference between the good and bad sleepers for many of the factors highlighted on websites offering advice on insomnia - including drinking alcohol or caffeine near to bedtime, or watching television in bed. (I do all of those.) © Copyright Reed Business Information Ltd.

Keyword: Sleep
Link ID: 12514 - Posted: 06.24.2010

by Sunita Reed New research published today says that insulin, the hormone used to treat diabetes, might some day be useful for treating or preventing Alzheimer’s disease. Neuroscientist Bill Klein and colleagues at Northwestern University had previously discovered evidence that Alzheimer’s disease might actually be a form of diabetes of the brain. Prior studies by other researchers found that patients with Alzheimer’s disease had lower levels of insulin, and that their brains were insulin-resistant. Klein discovered that, in addition to the plaques and tangles in brains of those with Alzheimer’s, there were toxic proteins called ADDLs (pronounced "ADD-els"). In normal brains, insulin binds to sites on cells called receptors, triggering a series of events that allow memories to form. By studying rat brain cell cultures in the lab, Klein’s team discovered how ADDLs can interfere with the memory-formation process. When they added the ADDLs, they attached to their own receptors on the cell surface and caused the insulin receptors to disappear. “Insulin in the brain is just not working,” explains Klein. Even though it’s there, it doesn’t have a place to park. Its receptors seem to be less responsive to the insulin. That’s the same thing that occurs in type 2 diabetes outside of the brain." In the current study, Klein and his colleagues at the Federal University of Rio de Janeiro, Brazil, tried a strategy to protect the insulin receptors from damage. Before adding ADDLs, they flooded the brain cells with a high concentration of insulin. The insulin treatment blocked the ADDLs from attaching to the ADDL receptors and completely protected the insulin receptors. ©2009 ScienCentral

Keyword: Alzheimers
Link ID: 12513 - Posted: 06.24.2010

By Joshua Hartshorne The setting: a nursery. A baby speaks directly to the camera: “Look at this. I’m a free man. I go anywhere I want now.” He describes his stock-buying activities, but then his phone interrupts. “Relentless! Hang on a second.” He answers his phone. “Hey girl, can I hit you back?” This E*Trade commercial is only the latest proof of what comedians have known for years: few things are as funny as a baby who talks like an adult. This comedic law obscures an important question: Why don’t young children express themselves articulately? And why is the idea of toddler speaking in perfect sentences so hilarious? Many people assume children learn to talk by copying what they hear. In other words, babies listen to the words adults use and the situations in which they use them and imitate accordingly. Behaviorism, the scientific approach that dominated American cognitive science for the first half of the 20th century, made exactly this argument. This “copycat” theory can’t explain why toddlers aren’t as loquacious adults, however. After all, when was the last time you heard literate adults express themselves in one-word sentences (“bottle,” “doggie”) or in short phrases such as, “Mommy open box.” Of course, showing that a copycat theory of language acquisition can’t explain these strange patterns in child speech is easy. Actually explaining one-word sentences is much harder. Over the past half-century, scientists settled on two reasonable possibilities. © 1996-2009 Scientific American Inc.

Keyword: Language; Development of the Brain
Link ID: 12512 - Posted: 06.24.2010

By BENEDICT CAREY They’re considered a release, a psychological tonic, and to many a glimpse of something deeper: the heart’s own sign language, emotional perspiration from the well of common humanity. Tears lubricate love songs and love, weddings and funerals, public rituals and private pain, and perhaps no scientific study can capture their many meanings. “I cry when I’m happy, I cry when I’m sad, I may cry when I’m sharing something that’s of great significance to me,” said Nancy Reiley, 62, who works at a women’s shelter in Tampa, Fla., “and for some reason I sometimes will cry when I’m in a public speaking situation. “It has nothing to do with feeling sad or vulnerable. There’s no reason I can think of why it happens, but it does.” Now, some researchers say that the common psychological wisdom about crying — crying as a healthy catharsis — is incomplete and misleading. Having a “good cry” can and usually does allow people to recover some mental balance after a loss. But not always and not for everyone, argues a review article in the current issue of the journal Current Directions in Psychological Science. Placing such high expectation on a tearful breakdown most likely sets some people up for emotional confusion afterward. Copyright 2009 The New York Times Company

Keyword: Emotions
Link ID: 12511 - Posted: 06.24.2010

By Bruce Bower Dreams don’t just bubble up at night and then evaporate like morning dew once the sun rises. What you dream shapes what you think about your upcoming plans and your closest confidants, especially if nighttime reveries fit with what’s already convenient to believe, a new report finds. In an effort to understand whether people take their dreams seriously, Carey Morewedge of Carnegie Mellon University in Pittsburgh and Michael Norton of Harvard University surveyed 149 college students attending universities in India, South Korea or the United States about theories of dream function. People across cultures often assume that dreams contain hidden truths, much as Sigmund Freud posited more than a century ago, Morewedge and Norton report in the February Journal of Personality and Social Psychology. In fact, many individuals consider dreams to provide more meaningful information regarding daily affairs than comparable waking thoughts do, the two psychologists conclude. Ideas that dreams come from the brain’s random output or are essential for daily problem-solving or for weeding out the routine clutter in one’s mind appeal to a minority of people, the scientists say. In a series of experiments, the researchers also probed interpretations of various real and imagined dreams in a national sample of 270 people surveyed online, 656 commuters and pedestrians interviewed in Boston and Cambridge, Mass., and 60 college students. © Society for Science & the Public 2000 - 2009

Keyword: Sleep
Link ID: 12510 - Posted: 06.24.2010

By Judy Foreman A troubled, gun-wielding 23-year-old student at Virginia Polytechnic Institute goes on a campus rampage, killing 32 people and eventually himself. An MIT student commits suicide by ingesting cyanide, and another dies in a fire after an overdose. Such highly publicized occurrences underscore the sense of personal angst on today's college campuses. But contrary to popular belief, the stress young people experience has nothing to do with meeting the demands of higher education. It comes simply with being a newly minted adult. Whether in college or not, almost half of this country's 19-to-25-year-olds meet standard criteria for at least one psychiatric disorder, although some of the disorders, such as phobias, are relatively mild, according to a government-funded survey of more than 5,000 young adults, published in December in the Archives of General Psychiatry. The study, done at Columbia University and called the National Epidemiologic Study on Alcohol and Related Conditions, found more alcohol use disorders among college students, while their noncollege peers were more likely to have a drug use disorder. But, beyond that, misery is largely an equal-opportunity affliction: Across the social spectrum, young people in America are depressed. They're anxious. They regularly break one another's hearts. And, all too often, they don't get the help they need as they face life's questions: © 2009 NY Times Co.

Keyword: Development of the Brain; Emotions
Link ID: 12509 - Posted: 06.24.2010

by Peter Aldhous GASTRIC surgery is a last resort for people who are dangerously obese. But there may soon be a gentler option in the shape of a removable device inserted into the gut though the mouth. The EndoBarrier, developed by GI Dynamics of Lexington, Massachusetts, is an impermeable sleeve that lines the first 60 centimetres of the small intestine. In animal experiments and preliminary human trials, it reduces weight and rapidly brings type II diabetes under control. Given the rising tide of obesity across the developed world, new treatments are a matter of priority. In the US alone, more than 15 million adults meet the criteria for gastric surgery because they have a body mass index of more than 40, or a BMI of 35 plus a complication such as diabetes. While the operations do cause dramatic and sustained weight loss, their high cost and concerns about the risk of dying on the operating table mean only a fraction of those who might benefit go on to have the surgery. According to the American Society for Metabolic and Bariatric Surgery, around 220,000 people in the US had gastric surgery for weight loss in 2008. GI Dynamics is not the only company working on alternatives (see "Wired for weight loss"), but its approach is appealing for its simplicity and low cost. The device, enclosed in a capsule, is inserted via the mouth using an endoscope. Once in place below the base of the stomach, the capsule releases a small ball that with the help of a catheter pulls a flexible sleeve made of the slippery polymer PTFE through the intestine. The ball is jettisoned and the sleeve fixed in place by releasing a spiked attachment made from the shape-memory metal alloy nitinol. © Copyright Reed Business Information Ltd.

Keyword: Obesity
Link ID: 12508 - Posted: 06.24.2010

By Carolyn Y. Johnson The humble honeybee can count - at least, sort of. New research shows that honeybees can tell the difference between different numbers of objects, up to four. That means the buzzing insects join the ranks of the numerically competent - pigeons, raccoons, dolphins, monkeys, songbirds, salamanders, and monkeys, all of which have been shown to have some form of numerical ability. The researchers are quick to note their results do not suggest that honeybees can actually put numbers in order or do math. But it does show bees can see features in visual patterns. Even if Pythagoras isn't at work in the hive, the work shines a light on an insect whose intellect is outsized for its buzzing body and minuscule brain. "Is it surprising? No. Is it amazing? Absolutely," said Kim Flottum, president of the Eastern Apicultural Society and editor of Bee Culture, who was not involved in the study. "Bees are just incredibly interesting . . . they just keep showing us things they can do that we didn't think anything as small as a bee should be able to do." To test bees' ability to recognize different numbers, researchers in Australia and Germany first trained bees to recognize one pattern of dots. The bees flew into a tunnel whose opening was marked with that pattern, then continued until they came to a fork in the tunnel, with the ability to go right or left. One choice was marked with the same dot pattern as the tunnel opening, the other with a different pattern. The bees that chose the matching pattern received a reward of sugar water. © 2009 NY Times Co.

Keyword: Miscellaneous
Link ID: 12507 - Posted: 06.24.2010

Reading a book triggers an active response in a person's brain, replicating the activity described in the story, a study by Washington University researchers in St. Louis, Mo., indicates. A brain-imaging study at Washington University tracked brain activity as participants read sections of a story. What scientists discovered was that parts of the brain associated with certain activities described in the story would light up as the person read those sections. For instance, if a character pulled a light cord in the story, the frontal lobe region, which controls grasping motions, would increase in activity. "There has been good evidence for a while that mental simulation — imagination — can improve performance in sport and other skilled behaviours. This study suggests that readers do mental simulation when they comprehend a story," Jeffrey Zacks, director of the university's dynamic cognition laboratory, told the Guardian newspaper. Zacks is also co-author of the study, soon to be published in the journal Psychological Science. The study's lead author is Nicole Speer. © CBC 2009

Keyword: Brain imaging; Language
Link ID: 12506 - Posted: 06.24.2010

By Carey Goldberg Marcie Lipsitt found that all she had to do was page Dr. Joseph Biederman or another doctor on his pediatric psychiatry team with that message, and she would get a call back within two minutes to help her through her son Andrew's latest violent crisis. Lynn Tesher credits the Biederman team at Massachusetts General Hospital with giving her several more years with her daughter, Ariel. Tormented from early childhood by rages and emotional pain, Ariel jumped to her death from her Manhattan balcony at age 20, but without the care from Biederman's team, Tesher is convinced, "she would not have lived past 13." For these mothers and some other parents, conflict-of-interest allegations against Biederman, one of the nation's leading child psychiatrists, are not just baffling, but personally upsetting. They see the doctor, a member of the Harvard Medical School faculty, being investigated by a powerful member of Congress and portrayed in the media as an apparent example of how drug company money taints medicine. To some, what is really under attack is child psychiatry, the research that aims to improve how it is practiced, and the terribly ill children who need help. US Senator Charles E. Grassley, Republican of Iowa, has accused Biederman of failing to tell Harvard until last March about most of the more than $1.5 million that the pharmaceutical industry paid him in consulting and speaking fees between 2000 and 2007. Biederman also created a research center with funding from Johnson & Johnson, a company that sells a popular antipsychotic drug. © 2009 NY Times Co.

Keyword: Development of the Brain; Schizophrenia
Link ID: 12505 - Posted: 06.24.2010

By Coco Ballantyne A Charlotte, N.C., man was charged with first-degree murder of a 79-year-old woman whom police said he scared to death. In an attempt to elude cops after a botched bank robbery, the Associated Press reports that 20-year-old Larry Whitfield broke into and hid out in the home of Mary Parnell. Police say he didn't touch Parnell but that she died after suffering a heart attack that was triggered by terror. Can the fugitive be held responsible for the woman's death? Prosecutors said that he can under the state's so-called felony murder rule, which allows someone to be charged with murder if he or she causes another person's death while committing or fleeing from a felony crime such as robbery—even if it's unintentional. But, medically speaking, can someone actually be frightened to death? We asked Martin A. Samuels, chairman of the neurology department at Brigham and Women's Hospital in Boston. Is it possible to literally be scared to death? Absolutely, no question about it. Really? How does that happen? The body has a natural protective mechanism called the fight-or-flight response, which was originally described by Walter Cannon [chairman of Harvard University's physiology department from 1906 to 1942]. If, in the wild, an animal is faced with a life-threatening situation, the autonomic (involuntary) nervous system responds by increasing heart rate, increasing blood flow to the muscles, dilating the pupils, and slowing digestion, among other things. All of this increases the chances of succeeding in a fight or running away from, say, an aggressive jaguar. This process certainly would be of help to primitive humans, but the problem, of course, is that in the modern world there is very limited advantage of the fight-or-flight response. There is a downside to revving up your nervous system like this. © 1996-2009 Scientific American Inc.

Keyword: Emotions; Stress
Link ID: 12504 - Posted: 06.24.2010