By NICHOLAS WADE The glue that binds a human society together is trust. But people who trust others too much are likely to get taken for a ride. Both trust and distrust, it now seems, are influenced by hormones that can induce people to ratchet their feeling of trust up or down. The trust side of the equation is mediated by a brain hormone known as oxytocin. A soft touch or caress will send a pulse of oxytocin into a person’s bloodstream. Swiss researchers found in 2005 that a squirt of oxytocin would make players in an investment game more willing to hand over their money to strangers. It may seem strange that there is a hormonal influence in such a delicate calculation as to whether or not to trust someone. But perhaps trust is so important to a society’s survival that natural selection has generated a hormonal basis for it. In any event, trust has a downside — one may hand over too much money to a Mr. Madoff who promises to generate steady returns in both up and down markets. There needs to be an antidote to oxytocin that makes a person keep those warm, fuzzy feelings suppressed in the appropriate circumstances. Researchers at Utrecht University in Holland now report that they have identified this antidote: it is testosterone. They gave young women a dose of the hormone in the form of a drop of liquid placed under the tongue, then asked them to judge the trustworthiness of a series of men’s faces shown in photographs. The women were significantly less inclined to trust a face when given testosterone than when they had taken a placebo, the Dutch team reported last month in The Proceedings of the National Academy of Sciences. Copyright 2010 The New York Times Company

Keyword: Hormones & Behavior
Link ID: 14161 - Posted: 06.24.2010

By Katherine Harmon Veterans of war have been known to suffer from high incidence of post-traumatic stress disorder (PTSD), depression and traumatic brain injury in addition to any physical wounds. And a new study of thousands of U.S. Army soldiers returning from combat duty in Iraq found up to 31 percent reported symptoms of PTSD or depression as long as a year after returning from the battlefield. Between 2004 and 2007, 18,305 soldiers returning from Active Component and National Guard infantry brigade combat teams completed surveys that screened for PTSD, depression and other trends, such as alcohol abuse, aggression and general difficulties getting along in civilian life, three months and a year after the soldiers returned from deployment in Iraq. Based on general definitions of the disorders, the researchers found that 20.7 percent to 30.5 percent of soldiers met the criteria for PTSD, and 11.5 percent to 16 percent met the criteria for depression. And "using the strictest definitions with high symptom rates and serious functional impairment," the authors found up to 11.3 percent of soldiers had PTSD and up to 8.5 percent suffered from depression. Between 8.5 percent and 14 percent of soldiers reported "serious functional impairment" due to their symptoms, the authors noted in their study, which was led by Jeffrey Thomas, of the Division of Psychiatry and Neuroscience at Walter Reed Army Institute of Research, and published online June 7 in Archives of General Psychiatry. © 2010 Scientific American,

Keyword: Stress
Link ID: 14160 - Posted: 06.24.2010

By Ferris Jabr Our eyes swivel restlessly in their sockets during rapid eye movement (REM) sleep, an aptly named period of intense dreaming that makes up 20 to 25 percent of total sleep time. Whether this fidgeting is random or serves a function has never been clear, but a new study suggests that our eyes shift their gaze to fixate on the imagined people, places and actions in our sleep dreamscape. In other words, the movements of dreaming eyes mimic those of waking eyes. For more than 50 years neuroscientists have debated the reasons for REM during sleep, proposing all kinds of ideas: the eyes roll around to lubricate the inside of the eyelids; jiggling eyes warm the brain; eyes twitch randomly in response to stimulation from the brain stem. According to a study in the June issue of Brain, the most likely explanation is the "scanning hypothesis," which says that throughout REM sleep our eyes orient their gaze to scan the imagery of our dreams—just as eyes change their gaze in response to our environment when we're awake and moving around. But how do researchers know where someone is looking while they dream? And how do they test whether that has anything to do with what someone is dreaming about? In the study neuroscientists at Pitié-Salpêtrière Hospital in Paris turned to a unique group of subjects: individuals with REM sleep behavior disorder (RBD). During REM sleep, the limb muscles of most people enter a state of temporary paralysis that prevents any flailing about. People with RBD do not go into sleep paralysis and physically act out their dreams—often with dramatic and violent actions: They kick, scream, grab, reach, climb and jump, both in their dreams and in reality, allowing researchers to observe what normally remains inside a dreamer's head. © 2010 Scientific American,

Keyword: Sleep; Vision
Link ID: 14159 - Posted: 06.24.2010

By Bruce Bower Where there’s secondhand cigarette smoke, there’s emotional fire. As exposure to cigarette fumes increases among nonsmokers, so does their risk of developing serious psychological distress and of being hospitalized for mental ailments, a new study finds. Cigarette smokers have been shown to have more psychological problems than nonsmokers do, and new evidence suggests that nonsmokers who inhale high levels of secondhand smoke may experience nearly as much psychological distress as smokers, say epidemiologist Mark Hamer of University College London and his colleagues. Overall, these findings support the view, largely based on animal studies, that nicotine administered in large enough doses can induce sadness and other negative moods, the researchers propose in the August Archives of General Psychiatry. “Our data are preliminary, but there is a strong possibility that the observed association reflects a causal link,” Hamer says. Previous research suggests that nicotine alters mood by disrupting immune responses, stress-hormone regulation and the transmission of dopamine, a chemical messenger in the brain. But little is known about nicotine’s possible relationship to specific psychiatric disorders. The link between nicotine exposure and mood held up after statistically accounting for participants’ social status, alcohol use, physical activity level, body mass index, chronic physical illness, level of psychological distress upon entering the study and previous hospitalizations for mental illness. © Society for Science & the Public 2000 - 2010

Keyword: Drug Abuse; Stress
Link ID: 14158 - Posted: 06.24.2010

by Linda Geddes Children with autism appear to have a characteristic chemical signature in their urine which might form the basis of an early diagnostic test for the condition. The finding also adds weight the hypothesis that substances released by gut bacteria are contributing to the onset of the condition. Autism has previously been linked to metabolic abnormalities and gastrointestinal problems such as gut pain and diarrhoea. Several studies have also hinted at changes in gut bacteria in the faeces of children with autism. To investigate whether signs of these metabolic changes might be detectable in children's urine, Jeremy Nicholson and colleagues at Imperial College London investigated 39 children with autism, 28 of their non-autistic siblings and 34 unrelated children. Using nuclear magnetic resonance (NMR) spectroscopy to analyse the children's urine, they found that each of these groups had a distinct chemical fingerprint, with clear and significant differences between children with autism and unrelated controls. "The signature that comes up is related to gut bacteria," says Nicholson. It is not yet clear whether the bacteria's metabolic products contribute to the development of autism, but it is a possibility worth investigating, he adds. A large proportion of autistic children have severe gastrointestinal problems that tend to appear at about the same time as the behavioural symptoms. © Copyright Reed Business Information Ltd.

Keyword: Autism
Link ID: 14157 - Posted: 06.24.2010

by Jim Giles The children of lesbian parents outscore their peers on academic and social tests, according to results from the longest-running study of same-sex families. The researchers behind the National Longitudinal Lesbian Family Study say the results should change attitudes to adoption of children by gay and lesbian couples, which is prohibited in some parts of the US. The finding is based on 78 children who were all born to lesbian couples who used donor insemination to become pregnant and were interviewed and tested at age 17. The new tests have left no doubt as to the success of these couples as parents, says Nanette Gartrell at the University of California, San Francisco, who has worked on the study since it began in 1986. Compared with a group of control adolescents born to heterosexual parents with similar educational and financial backgrounds, the children of lesbian couples scored better on academic and social tests and lower on measures of rule-breaking and aggression. A previous study of same-sex parenting, based on long-term health data, also found no difference in the health of children in either group. "This confirms what most developmental scientists have suspected," says Stephen Russell, a sociologist at the University of Arizona in Tucson. "Kids growing up with same-sex parents fare just as well as other kids." © Copyright Reed Business Information Ltd.

Keyword: Development of the Brain; Sexual Behavior
Link ID: 14156 - Posted: 06.24.2010

Answered by: Professor Andrew Smith Caffeine – 1,3,7-trimethylxanthine, to give it its chemical name – is a member of a group of naturally occurring substances called methylxanthines. These compounds are similar in structure to adenosines, naturally occurring molecules in our bodies which aid the onset of sleep. In its natural context, which is in tea and coffee plants, caffeine can kill or paralyse insects and is thus an effective natural pesticide. The earliest recorded caffeine consumers were in China in the 10th century BC, when philosophers believed tea-drinking was "an indispensable ingredient to the elixir of life". Coffee-quaffing originated in Yemen in the 15th century. The exact amount of caffeine present in a drink depends on its growing conditions and preparation. While tea naturally has more caffeine gramme for gramme than coffee, there is less tea per cubic centimetre of cup, leading to its weaker stimulant properties. For the record, in a 5oz cup of filter coffee, there is between 100mg and 150mg of caffeine. The same sized serving of tea holds 35-45mg. Meanwhile, a 12oz serving of cola contains just 40mg. Doctors say at least 100mg is necessary to properly increase our alertness. (A study published by Bristol University last week argued that caffeine can't make irregular users more alert; a cup of coffee in the morning, the research suggested, only counteracts the effects of withdrawal that have built up overnight.) How does it work? Adenosine bonds to receptor cells in the brain to calm the activity of the central nervous system, thus triggering tiredness. There is also evidence to suggest that it decreases blood flow in the brain. Caffeine molecules bind to these receptor cells but have no active effect on the nervous system. However by doing so they take the place of adenosine molecules that could make a difference. This process is known as "competitive inhibition" and effectively delays the onset of fatigue, increases alertness and improves people's ability to sustain attention. ©independent.co.uk

Keyword: Attention; Drug Abuse
Link ID: 14155 - Posted: 06.24.2010

Amy Maxmen A leading antipsychotic drug temporarily reduces the size of a brain region that controls movement and coordination, causing distressing side effects such as shaking, drooling and restless leg syndrome. Just two hours after injection with haloperidol, an antipsychotic commonly prescribed to treat schizophrenia, healthy volunteers experienced impaired motor abilities that coincided with diminished grey-matter volume in the striatum — a brain region that mediates movement. "We've seen changes in the brain before, but to see significant remodelling of the striatum within a couple of hours is staggering," says Clare Parish at the Howard Florey Institute for brain research in Melbourne, Australia, who was not involved in the study. "Our viewpoint was that only chemical changes would happen in such a short time." In functional magnetic resolution imaging (fMRI) scans the authors observed the participants' striatal volume diminishing and changes to the structure of the motor circuitry in their brains. Further, their reaction times slowed in a computer test taken after the treatment, indicating the onset of lapses in motor control that affect many patients on antipsychotics. © 2010 Nature Publishing Group,

Keyword: Schizophrenia; Brain imaging
Link ID: 14154 - Posted: 06.24.2010

By MATT RICHTEL SAN FRANCISCO — When one of the most important e-mail messages of his life landed in his in-box a few years ago, Kord Campbell overlooked it. Not just for a day or two, but 12 days. He finally saw it while sifting through old messages: a big company wanted to buy his Internet start-up. “I stood up from my desk and said, ‘Oh my God, oh my God, oh my God,’ ” Mr. Campbell said. “It’s kind of hard to miss an e-mail like that, but I did.” The message had slipped by him amid an electronic flood: two computer screens alive with e-mail, instant messages, online chats, a Web browser and the computer code he was writing. While he managed to salvage the $1.3 million deal after apologizing to his suitor, Mr. Campbell continues to struggle with the effects of the deluge of data. Even after he unplugs, he craves the stimulation he gets from his electronic gadgets. He forgets things like dinner plans, and he has trouble focusing on his family. His wife, Brenda, complains, “It seems like he can no longer be fully in the moment.” This is your brain on computers. Scientists say juggling e-mail, phone calls and other incoming information can change how people think and behave. They say our ability to focus is being undermined by bursts of information. Copyright 2010 The New York Times Company

Keyword: Attention
Link ID: 14153 - Posted: 06.24.2010

By PAUL BLOOM It is one of the most famous psychological demos ever. Subjects are shown a video, about a minute long, of two teams, one in white shirts, the other in black shirts, moving around and passing basketballs to one another. They are asked to count the number of aerial and bounce passes made by the team wearing white, a seemingly simple task. Halfway through the video, a woman wearing a full-body gorilla suit walks slowly to the middle of the screen, pounds her chest, and then walks out of the frame. If you are just watching the video, it’s the most obvious thing in the world. But when asked to count the passes, about half the people miss it. This experiment, published in 1999 by Christopher Chabris and Daniel Simons, is a striking demonstration of the zero-sum nature of attention. When you direct your mental spotlight to the basketball passes, it leaves the rest of the world in darkness. Even when you are looking straight at the gorilla (and other experiments find that people who miss it often have their eyes fully on it) you frequently don’t see it, because it’s not what you’re looking for. In “The Invisible Gorilla,” Chabris and Simons begin by talking about their study and its implications for everyday life. It is a mistake, they argue, to see it as revealing a bug in our software, rather than an inherent limitation. Our brains are physical systems and hence have finite ­resources. The real problem here — what Chabris and Simons call “the illusion of attention” ­— is that we are often unaware of these limitations; we think that we see the world as it really is, but “our vivid visual experience belies a striking mental blindness.” They go on to explore a series of related illusions having to do with perception, memory, knowledge and ability, providing vivid examples of the real-world problems these illusions cause. Copyright 2010 The New York Times Company

Keyword: Attention
Link ID: 14152 - Posted: 06.24.2010

By William Saletan Elizabeth Loftus warmed to the idea of memory tampering for the best of reasons. She wanted to help people. In her official career, as she described it in books, she studied the art of mental manipulation only to dissect, expose, and defeat it. Occasionally, she lent her psychological expertise to lawyers or advertisers for their self-interested purposes. But these purposes weren't hers, so she never turned them into a career. To embrace memory tampering, she needed a purpose of her own. Something she could believe in and care about. Something that could put her skills to good use. The story of how Loftus found that purpose—the story of her shadow career—began 30 years ago with a metaphor. "Imagine a world in which people could go to a special kind of psychologist or psychiatrist—a memory doctor—and have their memories modified," she mused in her 1980 book, Memory. This was no fantasy, she argued. The doctor was memory itself. "Every day, we do this to ourselves and others," she explained. "Our memories of past events change in helpful ways, leading us to be happier than we might otherwise be." Indeed, this was nature's design: Why should we cling tightly to those memories that disturb us and spoil our lives? Life might become so much more pleasant if it is not marred by our memory of past ills, sufferings, and grievances. … We seem to have been purposely constructed with a mechanism for erasing the tape of our memory, or at least bending the memory tape, so that we can live and function without being haunted by the past. Accurate memory, in some instances, would simply get in the way. © Copyright 2010 Washington Post.Newsweek Interactive Co. LLC

Keyword: Learning & Memory; Depression
Link ID: 14151 - Posted: 06.24.2010

By Katherine Harmon When your stomach growls and you have the urge to reach for the nearest snack, it is, in a way, your tummy talking. Those signals are in part sparked by the gut-based hunger hormone ghrelin, which blocks certain receptors in the brain, telling your body when it is time to eat. But a team of researchers thinks this hormone might be doing more than just urging you to pile on some calories. It might also be helping to regulate the levels of cholesterol in your bloodstream. The new research was published online June 6 in Nature Neuroscience (Scientific American is part of Nature Publishing Group). Although so-called bad cholesterol (low-density lipoprotein, or LDL) can result in clogged arteries and cardiovascular disease, good cholesterol (high-density lipoprotein, or HDL) is thought to actually prevent plaque build-up in the arteries by helping to transport lipids more smoothly through the bloodstream. Cholesterol levels have long been thought to be mainly a factor of diet and liver function. But new research in mouse models shows that changes in ghrelin and in a ghrelin-inhibited receptor in the hypothalamus altered how much HDL went to the liver for processing and how much remained in the blood stream. "Our study shows for the first time that cholesterol is also under direct 'remote control' by specific neurocircuitry in the central nervous system," Matthias Tschöp, a professor of endocrinology at the University of Cincinnati and coauthor of the paper, said in a prepared statement. © 2010 Scientific American,

Keyword: Obesity
Link ID: 14150 - Posted: 06.24.2010

A biological factor may play an essential part in the development of eating disorders in girls during puberty, a new study finds. The research, led by Michigan State University (MSU) scientists, finds that the genes of girls who have higher levels of estradiol at puberty can act as a catalyst for the development of eating disorders. Estradiol is the primary form of estrogen in women's bodies. It plays a key role in the development of secondary sex characteristics and bone development. "The reason we see an increase in genetic influences during puberty is that the genes for disordered eating are essentially getting switched on during that time," said Kelly Klump, MSU associate professor of psychology, in a release. "What we found is that increases in estradiol apparently are activating genetic risk for eating disorders." The genes responsible for activating eating disorders have yet to be identified. The researchers also believe that environmental factors and a genetic link (having a family history of eating disorders) play a part in the development of the condition. The researchers measured the amount of estradiol in the bloodstreams of 200 sets of twin girls between the ages of 10 and 15. The study is published in the journal Psychological Medicine. © CBC 2010

Keyword: Anorexia & Bulimia; Hormones & Behavior
Link ID: 14149 - Posted: 06.24.2010

By OLIVIA JUDSON A few weeks ago, I was walking through a wood in the English countryside when I heard the unmistakable call of the cuckoo. For some reason, it caused me to fall into a reverie, and as I walked, I began to meditate on that iconic bird and what it represents. The European cuckoo (Cuculus canorus) is, famously, a “brood parasite”: the female lays her eggs in other birds’ nests. Typical victims are small birds like reed warblers and wagtails. When the young cuckoo hatches, its first act is to dispose of any other eggs: it heaves them out of the nest, leaving itself as the sole occupant. What happens next is peculiar. The foster parents don’t appear to notice they are rearing a monster. Instead, they work hard to satisfy the demands of the chick, even though it sometimes becomes so large that it no longer fits inside the nest, and has to sit on top. It’s one of the oddest sights in nature. The cuckoo habit has evolved several times. It’s found in species as diverse as cowbirds, indigobirds, honeyguides and even a species of South American duck. (Actually, brood parasitism can also occur within a species — geese sometimes slip an egg into a neighbor’s nest, as do coots and starlings. Nor is it restricted to birds — fish and insects sometimes foist the rearing of their offspring onto others. But for the rest of this article, I want to focus on the birds that are “professional” brood parasites — the ones that, like the cuckoo, never build nests, and always palm their offspring onto another species.) Copyright 2010 The New York Times Company

Keyword: Sexual Behavior; Vision
Link ID: 14148 - Posted: 06.24.2010

By Nathan Seppa In science’s struggle to keep up with life on the streets, smoking cannabis for medical purposes stands as Exhibit A. Medical use of cannabis has taken on momentum of its own, surging ahead of scientists’ ability to measure the drug’s benefits. The pace has been a little too quick for some, who see medicinal joints as a punch line, a ruse to free up access to a recreational drug. But while the medical marijuana movement has been generating political news, some researchers have been quietly moving in new directions — testing cannabis and its derivatives against a host of diseases. The scientific literature now brims with potential uses for cannabis that extend beyond its well-known abilities to fend off nausea and block pain in people with cancer and AIDS. Cannabis derivatives may combat multiple sclerosis, Crohn’s disease and other inflammatory conditions, the new research finds. Cannabis may even kill cancerous tumors. Many in the scientific community are now keen to see if this potential will be fulfilled, but they haven’t always been. Pharmacologist Roger Pertwee of the University of Aberdeen in Scotland recalls attending scientific conferences 30 years ago, eager to present his latest findings on the therapeutic effects of cannabis. It was a hard sell. © Society for Science & the Public 2000 - 2010

Keyword: Drug Abuse; Pain & Touch
Link ID: 14147 - Posted: 06.24.2010

By Katherine Harmon NEW YORK—When ancient denizens of central France painted leaping horses on the cave walls at Lascaux, they might not have had the late Renaissance understanding of how to illustrate perspective and three dimensions. But they did, with simple black lines, give the implication of depth, showing the far pair of limbs behind the closer pair. That seemingly simple detail reveals a world of information about the human brain, concluded various scientists and artists at a World Science Festival panel held June 3 at New York University. In the world itself, lines do not define objects. "You cannot find objects that have lines around them," rather most people make sense of their surroundings using shapes, color, shading and subtleties of depth, explained Patrick Cavanagh, of the Vision Sciences Lab at Harvard University. By that measure, line drawings are "not something we've evolved to be able to understand," he said, but rather, people in all cultures—and even babies and monkeys—can understand a simple line drawing. The effectiveness of simple line-based representations "wasn't invented; it was discovered by artists," he noted. Cavanagh called this discovery "a backdoor to the brain," through which scientists can learn more about how the brain makes sense of the visual world: for instance, why we all understand that a straight line that ends at a square's edge and then continues on the same plane on the other side is probably "behind" the square—and why our brain has so much trouble sorting out even simple optical illusions. © 2010 Scientific American,

Keyword: Vision
Link ID: 14146 - Posted: 06.24.2010

by Gisela Telis The select club of brainy critters known for carrying traditions—among them humans, primates, whales, and dolphins—has an unlikely new member: the banded mongoose. Researchers have found that the furry African carnivore learns by imitation as well and carries what it learns well into adulthood. Experts say the discovery offers the first direct observation of animals passing down traditions in the wild. The mongoose is better known for its unique social system than for its brainpower. When mongoose pups emerge from the den, they try out and eventually choose one adult—usually an older sibling, cousin, or uncle, not a parent—who becomes their "escort" or chaperone during infancy. The escort protects, feeds, and plays with the pup as it grows, and the pair spends almost all its time together until the pup reaches adulthood. The relationship made Corsin Müller, an animal cognition expert at the University of Vienna, wonder if the escort teaches the pup any behaviors; that is, whether the escort is passing down "culture" or tradition to the pup. To find out, Müller and a colleague at the University of Exeter in the United Kingdom took advantage of another mongoose quirk. When eating hard-shelled prey, such as eggs or rhinoceros beetles, some mongooses bite into the item, others hurl it against a hard surface to smash it open, and still others switch between the techniques. Each mongoose sticks to its preferred behavior, even if other members of the same group choose a different tactic. Watch and learn. A mongoose escort smashes (top) or bites (bottom) a food-filled plastic egg as his pup looks on. As an adult, the pup will adopt its escort's preferred foraging technique or "tradition" during its own encounters with the egg. © 2010 American Association for the Advancement of Science.

Keyword: Learning & Memory; Sexual Behavior
Link ID: 14145 - Posted: 06.24.2010

by Sarah Reed A new movie set for general release today follows the lives of sexually liberated females. No, its stars are not the glamorous gals from Sex and the City. The film instead throws the spotlight on crickets, offering unprecedented video footage of the insect's mating behavior in the wild and confirming lab studies that have suggested female crickets have just as many different mates as males. Most studies of insect behavior have been confined to the laboratory, due to the technical challenges faced in monitoring these small creatures in the wild. Although laboratory-based studies have revealed much about the behavior and physiology of insects, it wasn't known how much the controlled environment influenced these findings. To address this issue, a team of European scientists monitored a population of flightless field crickets (Gryllus campestris) at the bottom of a river valley in northern Spain from the spring of 2006 through to the autumn of 2007. The crickets were under surveillance 24 hours a day, with a network of 64 motion-sensitive, infrared-equipped video cameras capturing a total of 250,000 hours of footage. Tags featuring a highly visible code were glued onto the backs of the crickets as soon as they emerged from their burrows so that they could be individually identified in the footage. Parentage was then assigned by extracting DNA from the tip of a hind leg. Caught on tape. In this video, Tom Tregenza of the University of Exeter narrates several scenes from the crickets' lives. © 2010 American Association for the Advancement of Science.

Keyword: Sexual Behavior; Evolution
Link ID: 14144 - Posted: 06.24.2010

Researchers have found a way to pharmacologically induce a memory of safety in the brain of rats, mimicking the effect of training. The finding suggests possibilities for new treatments for individuals suffering from anxiety disorders (http://www.nimh.nih.gov/health/topics/anxiety-disorders/index.shtml). Rats normally freeze when they hear a tone they have been conditioned to associate with an electric shock. The reaction can be extinguished by repeatedly exposing the rats to the tone with no shock. In this work, administering a protein directly into the brain of rats achieved the same effect as extinction training. The protein, brain-derived neurotrophic factor or BDNF, is one of a class of proteins that support the growth and survival of neurons. Prior work has shown that extinction training does not erase a previously conditioned fear memory, but creates a new memory associating the tone with safety. "The surprising finding here is that the drug substituted for extinction training, suggesting that it induced such a memory," said Dr. Gregory Quirk at the University of Puerto Rico School of Medicine, who led the investigation with support from the National Institute of Mental Health. The work is reported in the June 4 issue of Science. Memory formation involves changes in the connections, or synapses, between neurons, a process known as synaptic plasticity. One brain structure critical for extinction memory in rats is the infralimbic prefrontal cortex (ILC). Drugs that block synaptic plasticity impair the formation of extinction memory when injected into the ILC, causing rats to continue freezing at high levels after extinction training.

Keyword: Learning & Memory; Emotions
Link ID: 14143 - Posted: 06.05.2010

In a major study, investigators have compared how individuals with Parkinson's disease respond to deep brain stimulation (DBS) at two different sites in the brain. Contrary to current belief, patients who received DBS at either site in the brain experienced comparable benefits for the motor symptoms of Parkinson's. The results appear in the June 3, 2010 issue of the New England Journal of Medicine. This is the latest report from a study that has followed nearly 300 patients at 13 clinical sites for two years. The study was funded by the Department of Veterans Affairs (VA) and the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health. Additional support was provided by Minneapolis-based Medtronic, Inc., the makers of the DBS systems used in the study. "These results establish that DBS delivered to these two brain areas linked to key motor control pathways can have equivalent effects on tremor, stiffness and other motor symptoms of Parkinson’s disease," said Walter Koroshetz, M.D., deputy director at NINDS. "The important question now becomes how stimulation at each site affects some of the other important, non-motor symptoms and how to best individualize DBS therapy." Motor control problems such as shaking, rigidity, slowed movement and poor balance are often the first and most troubling symptoms of Parkinson’s disease. In later stages, patients tend to develop a variety of cognitive and mood problems, including depression, apathy, slowed thinking, confusion, impaired memory and trouble sleeping.

Keyword: Parkinsons
Link ID: 14142 - Posted: 06.24.2010