By Rachel Ehrenberg The kicks and somersaults of a developing baby aren’t the only in utero calisthenics. Babies also flex their mental muscles months before birth. Nerve cells from developing brains as young as 20 weeks old fire in a pattern that persists into adulthood, researchers report February 15 in the Journal of Neuroscience. The research provides a glimpse into the behavior of extremely young brain cells and could help scientists understand what happens when brain development goes awry. Cells from the cerebral cortices of 20- to 21-week-old fetuses exhibit bursts of electrical activity interspersed with periods of quiet, researchers from the University of Connecticut Health Center in Farmington found. When the adult brain is sleeping, or under anesthesia, it also displays this busy-then-quiet firing pattern, suggesting it may be an intrinsic property of human brains. The cerebral cortex deals with sensory information, thinking, emotion and consciousness. But even when not receiving input from the outside world, the nerve cells, or neurons, in this region oscillate between firing and resting. “In adults, we go to sleep and the cortex is disconnected from the outside environment — it sleeps alone. But you see this quiet synchronized activity,” says Igor Timofeev of Laval University in Québec. That young nerve cells behave in a similar way long before they grapple with outside input suggests that the firing pattern “is a very basic feature of the brain that occurs in very early stages of development,” says Timofeev. © Society for Science & the Public 2000 - 2011

Keyword: Development of the Brain
Link ID: 15009 - Posted: 02.17.2011

People who smoke cigarettes or have smoked in the past may be more likely to develop Lou Gehrig's disease, according to a new study. The disease slowly kills the neurons that send messages between the brain and the rest of the body, causing patients to lose control of their muscles -- including those that are essential for eating and breathing. Most people who are diagnosed with Lou Gehrig's disease, also known as amyotrophic lateral sclerosis, or ALS, don't survive more than five years after the diagnosis. About 20,000 to 30,000 people in the United States have ALS, according to the Centers for Disease Control and Prevention. While about 10 percent of those cases are caused by a genetic defect, the rest have no known cause. Some previous studies have suggested that smoking may be one factor that increases a person's risk of getting ALS, but others have found no link. "Results have been rather conflicting regarding the association between smoking and ALS," said Dr. Fang Fang, who has investigated the question at the Karolinska Institute in Stockholm, Sweden, but was not involved with the current study. Many ALS researchers tend to agree on a positive association between cigarette smoking and ALS risk although some quite-recent studies still report no link, he told Reuters Health in an e-mail. In the current study, researchers led by Dr. Hao Wang of the Harvard School of Public Health collected data from five long-term studies in the United States that altogether included more than a million adults. In all of the studies, participants had been asked if they currently smoked or had smoked in the past, and if so, how frequently and for how many years. Copyright 2011 Thomson Reuters.

Keyword: ALS-Lou Gehrig's Disease ; Drug Abuse
Link ID: 15008 - Posted: 02.15.2011

By Rachel Saslow Once, "relaxation beverages" consisted of alcohol, chamomile tea and warm milk. Now, the field includes a slew of new drinks promising a better night's sleep using such ingredients as melatonin, valerian root and - think turkey - tryptophan. They have apt names such as Unwind, iChill and Dream Water, and offer such flavors as Berry-Berry Tired, Snoozeberry and Lullaby Lemon. They're the inverse of energy drinks. Consumers can wake up with Red Bull and then wind down with Slow Cow. But can consumers trust these fruity concoctions to give them their z's? According to Steven M. Scharf, director of the Sleep Disorders Center at the University of Maryland in Baltimore, the answer is a resounding maybe. "The issue is this: Some of them probably have some biologic effect, but they haven't been as well studied as you'd like," Scharf says. "Nobody's ever compared valerian root to [the prescription sleep aid] Ambien." The chief ingredient in many of these beverages is melatonin, a hormone that induces sleepiness and helps coordinate the body's biological clock. It's typically released by the pineal gland around 10 p.m.; secretion stops around 4 or 5 a.m., helping to trigger the body to wake up, Scharf says. The body produces about three-fourths of a milligram of melatonin a day. The manufacturer of the sleep aid Snooz'n says its 2.5-ounce "shots" contain five milligrams of melatonin; Unwind, a "relaxation blend," has three milligrams per 12-ounce can. © 2011 The Washington Post Company

Keyword: Sleep; Hormones & Behavior
Link ID: 15007 - Posted: 02.15.2011

By MARC E. AGRONIN, M.D. The woman described the sensation as a delicate flicker, like a moth trapped in a small gauze bag. She ran her slender fingers repeatedly over the spot in her slightly distended abdomen and said, “Doctor, right here.” Sometimes, she told me, the flicker gave way to a more forceful kick that rippled beneath her hand and then spread like a warm tide over her body. She felt contented and soothed as she imagined the baby growing inside. I was tempted to smile, but I kept still. An actual pregnancy would have been international news: the woman was 83 years old, recovering from a hip fracture and pneumonia. But her delusion was not unique. Indeed, our nursing home was having something of a baby boom. Just the day before, another woman who had recently suffered a stroke insisted that she had given birth to twin boys, who were now crying in the adjacent nursery. I reminded her that she was 90, but my words were no match for the force of her belief. She looked at me blankly and called again for her babies. Her husband, distraught, begged me to consider some pharmacologic remedy. But I was struck not by any mental suffering on the woman’s part, but by the opposite. In the face of terrible losses and confusion, her mind had found refuge in imaginary children. Their coos and cries brought comfort and hope. © 2011 The New York Times Company

Keyword: Stroke; Attention
Link ID: 15006 - Posted: 02.15.2011

By BENEDICT CAREY In recent years, many psychiatrists have come to believe that the last, best chance for some people with severe and intractable mental problems is psychosurgery, an experimental procedure in which doctors operate directly on the brain. Hundreds of people have undergone brain surgery for psychiatric problems, most in experimental trials, with some encouraging results. In 2009, the government approved one surgical technique for certain severe cases of obsessive-compulsive disorder, or O.C.D. For the first time since frontal lobotomy fell into disrepute in the 1950s, surgery for behavior problems seemed back on the road to the medical mainstream. But now some of the field’s most prominent scientists are saying, “Not so fast.” In a paper in the current issue of the journal Health Affairs, these experts say approving the surgery for O.C.D. was a mistake — and a potentially costly one. They argue that the surgery has not been sufficiently tested, that neither its long-term effectiveness nor its side effects are well known and that even calling it “therapy” raises people’s hopes well beyond what is scientifically supportable. “We’re not against the operation, we just want to see it tested adequately before it’s called a therapy,” said the paper’s lead author, Dr. Joseph J. Fins, chief of medical ethics at NewYork-Presbyterian/Weill Cornell hospital. “With the legacy of psychosurgery, it’s important that we don’t misrepresent things as therapy when they’re not.” Doctors who run programs offering the operation strongly object. “These patients are very capable of making informed decisions based on our experience with the surgery,” said Dr. Wayne K. Goodman, chairman of psychiatry at the Mount Sinai School of Medicine, “and I would not want to deprive them of the option, any more than I would deny someone with AIDS access to a promising therapy that has not been established yet. Their life has been so destroyed by O.C.D. that they might contemplate suicide” if the surgery were not available. © 2011 The New York Times Company

Keyword: OCD - Obsessive Compulsive Disorder
Link ID: 15005 - Posted: 02.15.2011

By KATHERINE BOUTON Imagine, Michael Chorost proposes, that four police officers on a drug raid are connected mentally in a way that allows them to sense what their colleagues are seeing and feeling. Tony Vittorio, the captain, is in the center room of the three-room drug den. He can sense that his partner Wilson, in the room on his left, is not feeling danger or arousal and thus has encountered no one. But suddenly Vittorio feels a distant thump on his chest. Sarsen, in the room on the right, has been hit with something, possibly a bullet fired from a gun with a silencer. Vittorio glimpses a flickering image of a metallic barrel pointed at Sarsen, who is projecting overwhelming shock and alarm. By deducing how far Sarsen might have gone into the room and where the gunman is likely to be standing, Vittorio fires shots into the wall that will, at the very least, distract the gunman and allow Sarsen to shoot back. Sarsen is saved; the gunman is dead. That scene, from his new book, “World Wide Mind,” is an example of what Mr. Chorost sees as “the coming integration of humanity, machines, and the Internet.” The prediction is conceptually feasible, he tells us, something that technology does not yet permit but that breaks no known physical laws. © 2011 The New York Times Company

Keyword: Robotics; Hearing
Link ID: 15004 - Posted: 02.15.2011

By Mark Fischetti A dozen brain regions, working together, create feelings of passionate love. Stephanie Ortigue of Syracuse University and her colleagues worldwide compared MRI studies of people who indicated they were either in love or were experiencing maternal or unconditional love. The comparison revealed a "passion network"—the red regions shown here at various angles. The network releases neurotransmitters and other chemicals in the brain and blood that create the sensations of attraction, arousal, pleasure…and obsession. For more details on how the network affects cognitive functions, see "Graphic Science: Your Brain in Love" in the February 2011 issue of Scientific American. Graphic by James W. Lewis, West Virginia University © 2011 Scientific American

Keyword: Sexual Behavior; Brain imaging
Link ID: 15003 - Posted: 02.15.2011

by Wendy Zukerman Is it that time of the month? These are the words no man should ever utter. How about this for a diplomatic alternative: "Are your GABA receptors playing up?" You may be spot on. It seems that these brain cells are to blame for some women's monthly mood swings. Many women feel a little irritable before menstruating, but up to 8 per cent suffer extreme symptoms, including anxiety, depression and fatigue. Symptoms of what's called premenstrual dysphoric disorder (PMDD) begin around a week before menstruation when women are in the "late luteal phase" of their cycle and progesterone levels are at their height. Symptoms quickly subside after menstruation, once the so-called "follicular phase" has kicked in. To investigate potential mechanisms behind PMDD, Andrea Rapkin at the University of California, Los Angeles used a PET scan, which shows where glucose is being metabolised to identify activity in the brain. The idea was to analyse the brain activity of 12 women with PMDD and 12 without the condition, at various times throughout their menstrual cycle. Before each scan, the women rated the severity of any symptoms they had on a scale of one to six. Blood samples were also taken to test their hormone levels. Fluctuating hormones were not to blame: all the women experienced similar jumps in progesterone levels throughout their cycle, irrespective of whether they had PMDD or not. © Copyright Reed Business Information Ltd.

Keyword: Hormones & Behavior; Emotions
Link ID: 15002 - Posted: 02.15.2011

by Rachel Courtland How does a nose generate the signals that the brain registers as smell? The conventional theory says it's down to the different shapes of smelly molecules. But fruit flies have now distinguished between two molecules with identical shapes, providing the first experimental evidence to support a controversial theory that the sense of smell can operate by detecting molecular vibrations. The noses of mammals, and the antennae of flies, are lined with different folded proteins that form pocket-shaped "receptors". It has been generally assumed that a smell arises when an odour molecule slides into a receptor like a key in a lock, altering the receptor's shape and triggering a cascade of chemical events that eventually reach the brain. But this "shape" theory has limitations. For one, it can't easily explain why different molecules can have very similar smells. In 1996, Luca Turin, a biophysicist now at the Massachusetts Institute of Technology, proposed a solution. He revived a theory that the way a molecule vibrates can dictate it odour, and came up with a mechanism to explain how this might work. His idea was that electrons might only be able to pass across a receptor if it was bound to a molecule that vibrated at just the right frequency. Ordinarily, the energy needed for the electron to make this journey would be too great, but the right vibrational energy could prompt a quantum effect in which the electron "tunnels" through this energy barrier, and this would then be detected and registered as a particular smell (see diagram). © Copyright Reed Business Information Ltd.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 15001 - Posted: 02.15.2011

By JAMES DAO, BENEDICT CAREY and DAN FROSCH In his last months alive, Senior Airman Anthony Mena rarely left home without a backpack filled with medications. He returned from his second deployment to Iraq complaining of back pain, insomnia, anxiety and nightmares. Doctors diagnosed post-traumatic stress disorder and prescribed powerful cocktails of psychiatric drugs and narcotics. Yet his pain only deepened, as did his depression. “I have almost given up hope,” he told a doctor in 2008, medical records show. “I should have died in Iraq.” Airman Mena died instead in his Albuquerque apartment, on July 21, 2009, five months after leaving the Air Force on a medical discharge. A toxicologist found eight prescription medications in his blood, including three antidepressants, a sedative, a sleeping pill and two potent painkillers. Yet his death was no suicide, the medical examiner concluded. What killed Airman Mena was not an overdose of any one drug, but the interaction of many. He was 23. After a decade of treating thousands of wounded troops, the military’s medical system is awash in prescription drugs — and the results have sometimes been deadly. By some estimates, well over 300,000 troops have returned from Iraq or Afghanistan with P.T.S.D., depression, traumatic brain injury or some combination of those. The Pentagon has looked to pharmacology to treat those complex problems, following the lead of civilian medicine. As a result, psychiatric drugs have been used more widely across the military than in any previous war. © 2011 The New York Times Company

Keyword: Stress; Depression
Link ID: 15000 - Posted: 02.14.2011

NEW YORK — Compared to a sleek new laptop, that three-pound mass of fatty tissue called the brain may not look like much. But when it's injured, it adapts and rewires its circuits in new ways. That's the kind of flexibility that doctors and rehabilitation specialists hope to encourage in Gabrielle Giffords, the brain-injured Arizona congresswoman. Details about her recovery have been thin. But members of her staff say she recently began speaking for the first time since the Jan. 8 attack by a gunman in Tucson. Brain injury patients who regain speech typically begin to do that about four to six weeks after the injury, experts say. Still, recovery for the 40-year-old Giffords will be a long, tough journey, as it is for anyone with a significant brain injury. Patients can make remarkable progress. But experts caution that they shouldn't expect to return to exactly the way they were before. Too little has been revealed and it's too early to say if Giffords might be able to return to her job in Congress. One expert questioned whether that would be the best thing for her to do. Most people with such injuries have some level of impairment for the rest of their lives. The New York Times on Sunday reported that some of Giffords' efforts to relearn how to speak include mouthing the words to song lyrics, such as "Twinkle, Twinkle, Little Star," and briefly talking with her brother-in-law by telephone while he orbited aboard the International Space Station. Copyright 2011 The Associated Press.

Keyword: Regeneration; Brain Injury/Concussion
Link ID: 14999 - Posted: 02.14.2011

By Gary Stix A debate rages on whether President Reagan did or didn't have Alzheimer's disease during his time in office. With what we have learned in the last decade about the disease, the question is relatively meaningless, except perhaps to score political points. The simple answer: of course he did. The newest technology—consisting of imaging and spinal taps—shows that the disease process begins its relentless course as many as 15 years before a firm diagnosis. By the time the first symptoms appear, the disease is already progressing. While in office, Reagan had moments of incomprehension interspersed with fully lucid thinking. So Reagan was well along the glide path to dementia when he was staring down the Evil Empire. The beloved conservative acronym WWRD might have been reframed: WSHBDAR: What Should Have Been Done About Reagan. It doesn't really matter. Reagan will retain his exalted status within conservative hagiography. The more interesting question lurks ahead for future presidential candidates. The most significant advance in the Alzheimer's field in recent years is the advent of these imaging and spinal fluid "biomarkers" that can probe the course of the disease years before the first symptom. The techniques might not be fully ready for prime time, but they're getting there fast. In January, an FDA advisory panel voted to recommend, with just a few conditions, the approval of an imaging test that shows in living patients the buildup of the amyloid protein fragments characteristic of the disease. © 2011 Scientific American

Keyword: Alzheimers
Link ID: 14998 - Posted: 02.14.2011

By Emily Sohn People love music for much the same reason they're drawn to sex, drugs, gambling and delicious food, according to new research. When you listen to tunes that move you, the study found, your brain releases dopamine, a chemical involved in both motivation and addiction. Even just anticipating the sounds of a composition like Vivaldi's "Four Seasons" or Phish's "You Enjoy Myself" can get the feel-good chemical flowing, found the study, which was the first to make a concrete link between dopamine release and musical pleasure. The findings offer a biological explanation for why music has been such a major part of major emotional events in cultures around the world since the beginning of human history. Through music, the study also offers new insights into how the human pleasure system works. "You're following these tunes and anticipating what's going to come next and whether it's going to confirm or surprise you, and all of these little cognitive nuances are what's giving you this amazing pleasure," said Valorie Salimpoor, a neuroscientist at McGill University in Montreal. "The reinforcement or reward happens almost entirely because of dopamine." "This basically explains why music has been around for so long," she added. "The intense pleasure we get from it is actually biologically reinforcing in the brain, and now here's proof for it." © 2011 Discovery Communications, LLC.

Keyword: Hearing; Emotions
Link ID: 14997 - Posted: 02.14.2011

Dr. Russell A. Barkley First, it is important to note that attention deficit hyperactivity disorder does not present all that much differently in women from the way it does in men. Most research on this issue has confirmed this. While symptoms may vary somewhat among children, they are virtually the same by adulthood. In childhood, boys are three times as likely as girls to have A.D.H.D. Boys with the disorder tend to be more hyperactive and impulsive and are more likely to develop oppositional behavior, conduct problems and later delinquency than girls, though girls, too, can develop these problems. Girls, on the other hand, may be more prone to develop anxiety, depression and eating disorders — bulimia, in particular. By adulthood, the proportion of men to women with the disorder is nearly even, and there are few differences in the symptoms. Both men and women have significant problems with executive functioning, which involves skills like time management, self-organization and problem-solving, as well as self-restraint, self-motivation and self-regulation of emotions. All of these problems can have a major effect on daily life activities, like family relations, child-rearing, managing money, functioning at work or driving. Where men and women may differ is in the amount of time they engage in these activities – and the subsequent impact on daily life. A woman who works full time outside the home, for instance, would have more work-related difficulties, whereas a stay-at-home mother might have more problems related to home life. To the extent that women may opt for certain roles, those roles will be more greatly affected by the disorder, and vice versa for men. © 2011 The New York Times Company

Keyword: ADHD; Sexual Behavior
Link ID: 14996 - Posted: 02.12.2011

By Wynne Parry Experience can be a disadvantage, since preconceptions may limit our ability to creatively solve a problem we think we've seen before. However, stimulating the brain in a certain way may provide flashes of insight, according to two scientists. In a study of 67 adults, researchers found that electrical stimulation of two parts of the brain prompted three times as many participants to come up with an insightful solution to a puzzle compared with those who didn't receive a brain zap. "Our experiences can blind us," Richard Chi and Allan Snyder, researchers at the Center for the Mind at the University of Sydney in Australia, write in the Feb. 2 issue of the journal PLoS ONE. "Once we have learned to solve problems by one method, we often have difficulties in generating solutions involving a different kind of insight." Chi and Snyder set out to induce a temporary mental state less constrained by preconceptions, focusing on the brain's anterior temporal lobes, located just above the ears. The left anterior temporal lobe is associated with maintaining existing concepts and representations of these concepts; research has shown that when this brain region is inhibited, people are less likely to draw on their preconceived notions. The right anterior temporal lobe, meanwhile, is associated with insight. They gave study participants "matchstick arithmetic" puzzles, in which matchsticks spelled out inaccurate equations in Roman numerals. Participants had to correct the statements by moving only one stick. They first solved 27 puzzles all with a particular type of solution — making an "X" into a "V." © 2011 LiveScience.com.

Keyword: Attention
Link ID: 14995 - Posted: 02.12.2011

Ewen Callaway Sex and violence are intertwined in mice. A tiny patch of cells buried deep within a male's brain determines whether it fights or mates, and there is good reason to believe humans possess a similar circuit. The study, published in Nature today1, shows that when these neurons are quieted, mice ignore intruding males they would otherwise attack. Yet when the cells are activated, mice assault inanimate objects, and even females they ought to court. The cells lie within an area of the hypothalamus with known links to violent behaviour. An electrical jolt to this vicinity causes cats and rats to turn violent, but neurophysiological experiments conducted decades ago stimulated too big an area to identify the specific brain circuits, let alone the individual neurons, involved in aggression. More recently, scientists studying mice engineered to lack specific genes have found that some of them act more aggressively than normal mice. "We really don't know which part of the brain went wrong in those mice. Consequently it's tough to make sense of that behaviour," says Dayu Lin, a neuroscientist now at New York University and an author of the study, who began searching for the seat of aggression in mice while working with David Anderson at the California Institute of Technology in Pasadena. © 2011 Nature Publishing Group,

Keyword: Aggression; Sexual Behavior
Link ID: 14994 - Posted: 02.12.2011

By Janet Raloff On his third consecutive evening of air combat, a military pilot closes in on the night’s quarry, a suspected Taliban fuel depot in Afghanistan. Fatigued, his alertness flagging, the pilot throws some chewing gum into his mouth. Laced with caffeine, it’s the cockpit alternative to a cup of coffee. This pilot would probably suspect that the gum is just a perk-me-up. But several caffeinated military rations — including this relatively new one — do more than stave off sleepiness. Emerging data indicate that these rations boost not only attention but also cognitive performance, features that do not necessarily climb in lockstep. The U.S. Department of Defense has been investigating such supplements to improve the ability of U.S. armed forces to maintain sustained periods of intense vigilance and focus, explains Harris Lieberman, a psychologist at the Army Research Institute of Environmental Medicine in Natick, Mass. Another hope, he notes: These dietary aids might minimize the risk of “friendly fire.” Army researchers at the institute, including Lieberman, are at the forefront of a small but growing cadre of investigators exploring how to boost what they call mental energy. This rather fuzzy phrase embraces wakefulness, but also includes mood, motivation and the capacity to perform key mental tasks. Increasing mental energy is important for those enervated because of a lack of sleep or for those whose jobs, like those of fighter pilots, require vigilance even in the face of sleep deprivation. Compounds that keep you awake, it turns out, can also boost other aspects of mental performance. Improved cognition is emerging as a quantifiable side benefit of many of these substances — in some cases, even for those folks who aren’t sleepy to begin with. © Society for Science & the Public 2000 - 2011

Keyword: ADHD; Drug Abuse
Link ID: 14993 - Posted: 02.12.2011

New research shows a link between use of two pesticides, rotenone and paraquat, and Parkinson's disease. People who used either pesticide developed Parkinson’s disease approximately 2.5 times more often than non-users. "Rotenone directly inhibits the function of the mitochondria, the structure responsible for making energy in the cell," said Freya Kamel, Ph.D., a researcher in the intramural program at NIEHS and co-author of the paper appearing online in the journal Environmental Health Perspectives. "Paraquat increases production of certain oxygen derivatives that may harm cellular structures. People who used these pesticides or others with a similar mechanism of action were more likely to develop Parkinson's disease. The authors studied 110 people with Parkinson’s disease and 358 matched controls from the Farming and Movement Evaluation (FAME) Study (http://www.niehs.nih.gov/research/atniehs/labs/epi/studies/fame/index.cfm) to investigate the relationship between Parkinson’s disease and exposure to pesticides or other agents that are toxic to nervous tissue. FAME is a case-control study that is part of the larger Agricultural Health Study (http://www.niehs.nih.gov/research/atniehs/labs/epi/studies/ahs/index.cfm), a study of farming and health in approximately 90,000 licensed pesticide applicators and their spouses. The investigators diagnosed Parkinson's disease by agreement of movement disorder specialists and assessed the lifelong use of pesticides using detailed interviews.

Keyword: Parkinsons; Neurotoxins
Link ID: 14992 - Posted: 02.12.2011

Jessica Marshall Mild-mannered male squid turn into furious fighting machines when their tentacles brush a chemical on the surface of squid eggs, a finding that could give insights into how aggression works. The discovery also reveals how male squid compete for female mating partners. "I think that this is really a novel and kind of wonderful addition to our understanding of how aggression might work," said Russell Fernald of Stanford University, who was not a part of the study. Researchers diving on squid spawning grounds had noticed that not just female squid would hang around the many mop-like clusters of egg capsules. "We noticed underwater that the males were attracted to the eggs, too. This made no sense. All the eggs are fertilized already. This caught our attention," lead author Roger Hanlon of the Marine Biological Laboratory in Woods Hole, Mass. told Discovery News. A key to solving the puzzle came during a Cape Cod dive. "There was absolutely nothing that was happening, it was Deadsville." Hanlon said. So, he fetched some squid eggs from the boat and brought them back to the dive site. "I just put the squid eggs on the bottom. Within a minute or two, one bold male squid went down and touched them. He came back up to the squid above him and started fighting with other squid." © 2011 Discovery Communications, LLC.

Keyword: Aggression; Sexual Behavior
Link ID: 14991 - Posted: 02.12.2011

By Susan Gaidos You know the feeling — the flush of excitement when your boss hands you a bonus check, or you unexpectedly run into an old friend, or you discover a way to get tickets to the big game that was long ago sold out. When life throws you a gift or a gain, it’s not just your mood that perks up. Two small almond-shaped masses of nerve cells buried deep in your brain take notice too. Those clumps of cells, one on each side of the brain, are known as the amygdala (uh-MIG-duh-luh). For years the amygdala has been regarded primarily as the brain’s center for fear. Scores of studies have shown that it is essential both for perceiving fear and expressing it. In recent years, though, a surge of new research has expanded scientists’ view of the amygdala’s importance. It turns out that the amygdala helps shape behavior in response to all sorts of stimuli, bad and good. It plays a role not only in aversion to fright, but also in pursuit of pleasure. Studies of the brain’s anatomy reveal good reasons for the amygdala’s power: It is very well connected. In humans and other primates, the amygdala is linked through a complex network of cells to brain regions involved in all five senses. Signals about everything you encounter are passed from the brain’s sensory processing areas directly to the amygdala. And the amygdala shares elaborate communications channels with the prefrontal cortex — the brain’s control center for planning and decision making. © Society for Science & the Public 2000 - 2011

Keyword: Emotions
Link ID: 14990 - Posted: 02.12.2011