Boston = Researchers at The Forsyth Institute have discovered that the transport mechanisms for serotonin — the chemical substance involved in transmitting signals between neurons, and which has a role in anxiety and mood disorders — play a key role in determining where organs are positioned in the body during embryonic development. Transporters bring serotonin into cells. The research team, led by Dr. Michael Levin, found that when the transport of serotonin into cells was blocked, normal development was disrupted in frog and chick embryos. In particular, left-right asymmetry, the process through which cells “know” which side they are on as they form body organs such as the heart and liver, is controlled by serotonin transporters. Michael Levin, PhD., Associate Member of the Staff, conducted his research with substances commonly used to treat mood disorders in humans including the drug Prozac. These drugs address chemical imbalances in the brain by blocking serotonin’s removal from the space between neurons. “With this research, we’ve not only identified a novel role of the serotonin transporters, in contributing to left-right asymmetry, but have also confirmed that serotonin has a role in cells other than neurons,” Levin said. “This raises interesting questions related to embryonic development and also about the possible subtle side-effects of serotonin-related drugs like the selective serotonin reuptake inhibitors (SSRI antidepressants such as Prozac and Zoloft) or the monoamine oxidase inhibitors (MAOIs).” Copyright 2004, Forsyth Institute

Keyword: Development of the Brain
Link ID: 8235 - Posted: 06.24.2010

Stefan Lovgren for National Geographic News Normally cautious mice can be turned into daredevils by removing a gene in their brain that regulates fear, a new study has found. Scientists say stathmin, a gene that is normally present in high levels in a part of mammals' brains called the amygdala, controls both innate and learned fear. Switching off the gene makes a fearful mouse courageous. The discovery provides important information on how fear is experienced and processed. It could have important implications for the study of anxiety disorders in humans, and may aid in the development of gene-based therapies to treat such diseases. "Because stathmin controls both instinctive and learned fear, it provides genetic means to study how these two types of fear work and interact to govern our emotions," said Gleb Shumyatsky, a genetics professor at Rutgers University in New Brunswick, New Jersey. Shumyatsky is the lead author on the study, which was reported in the November 18 issue of the science journal Cell. © 1996-2005 National Geographic Society.

Keyword: Emotions; Genes & Behavior
Link ID: 8234 - Posted: 06.24.2010

The first images ever made of retinas in living people reveal surprising variation from one person to the next. Yet somehow our perceptions don't vary as might be expected. As they took pictures of the thousands of cells responsible for detecting color in the deepest layer of the eye, scientists found that our eyes are wired differently. Yet we all — with the exception of the colorblind — identify colors similarly. The results suggest that the brain plays an even more significant role than thought in deciding what we see. The eye, responsible for receiving visual images, is wrapped in three layers of tissue. The innermost layer, the retina, is responsible for sensing color and sending information to the brain. The retina contains light receptors known as cones and rods. These receptors receive light, convert it to chemical energy, and activate the nerves that send messages to the brain. The rods are in charge of perceiving size, brightness and shape of images, whereas color vision and fine details are the responsibility of the cones. © 2005 MSNBC.com © 2005 Microsoft

Keyword: Vision
Link ID: 8233 - Posted: 06.24.2010

The more creative a person is, the more sexual partners they are likely to have, according to a pioneering study which could explain the behaviour of notorious womanisers such as poets Lord Byron and Dylan Thomas. The research, by the University of Newcastle upon Tyne and the Open University in the UK, found that professional artists and poets have around twice as many sexual partners as those who do not indulge in these creative activities. The authors also delved into the personalities of artists and poets and found they shared certain traits with mentally ill patients. These traits were linked with an increased sexual activity and are thought to have evolved because they contribute to the survival of the human species. Some 425 British men and women, including a sample of visual artists and poets and schizophrenic patients, were surveyed for the report, which is published today in the academic journal, The Proceedings of the Royal Society (B). Although creative types have long been associated with increased sexual activity, this the first time that this link has been proved by research. Study participants filled in questionnaires which asked about their degree of creative activity in poetry and visual art, their psychiatric history, and their history of sexual encounters since the age of 18. They were also required to answer questions on a 'schizotypy inventory', a breakdown of characteristics linked with schizophrenic patients.

Keyword: Sexual Behavior
Link ID: 8232 - Posted: 11.30.2005

By Jennifer Viegas, Discovery News — The sexy sounds emitted by male pigeons send female pigeons into the bird version of rapture, and such vocalizations seem to affect the females more than when they watched a desirous male strut his stuff, a recent study determined. Since the males usually vocalize and strut at the same time, the findings suggest the strutting may be "redundant," meaning that it serves the same function as the sounds to hammer home a point, which in this case is that the male wants to mate. Humans communicate using comparable signals, such as when a person might raise his or her eyebrows while at the same time asking someone, "Care to dance?" The eyebrow move alone might be misunderstood or ignored, but together the facial expression and words suggest what the speaker is thinking. "The acoustic signals were very salient to the birds: when the females could hear but not see the males, they responded with some courtship behavior (circle walking and spreading their tails), but most importantly they began to coo," said lead author Sarah Partan, whose research was outlined in a recent issue of the journal Animal Behavior. © 2005 Discovery Communications Inc.

Keyword: Sexual Behavior; Language
Link ID: 8231 - Posted: 06.24.2010

By Michael Purdy — By peering into the minds of volunteers preparing to play a brief visual game, neuroscientists at Washington University School of Medicine in St. Louis have found they can predict whether the volunteers will succeed or fail at the game. "Before we present the task, we can use brain activity to predict with about 70 percent accuracy whether the subject will give a correct or an incorrect response," says lead author Ayelet Sapir, Ph.D., a postdoctoral research associate in neurology. Eleven seconds before volunteers played the game — discriminating the direction of a field of moving dots — scientists showed them a hint: an arrow pointing to where the moving dots were likely to appear. The dots were visible only for one-fifth of a second and therefore were easy to miss if a subject was not paying attention to the right area. After the hint and prior to the appearance of the moving dots, researchers scanned the volunteers with functional brain imaging, which reveals increases in blood flow to different brain areas indicative of increased activity in those regions. Based on brain activity patterns that reflected whether the subjects used the hint or not, scientists found they could frequently predict whether a volunteer's response would be right or wrong before the volunteers even had a chance to try to see the dots.

Keyword: Attention; Vision
Link ID: 8230 - Posted: 06.24.2010

A popular treatment for nicotine addiction can also cut cravings among crystal meth addicts, a US study suggests. Crystal meth – the commonly used term for methamphetamine – is a cheap and addictive drug that has become a massive problem in the US in recent years. It increases alertness and creates sensations of euphoria in users by stimulating the generation of dopamine and norepinephrine – neurotransmitters within the regions of the brain responsible for feelings of pleasure. Bupropion – the active chemical ingredient found in the nicotine addiction drug, Zyban, as well as the anti-depressant Wellbutrin – was found to reduce the drug-induced high experienced by methamphetamine users and also to lessen their urge to take the drug in response to visual cues, in a study by researchers at the University of California in Los Angeles (UCLA). Twenty methamphetamine users were given either 150 milligrams of bupropion twice a day for a week, or a placebo. Subjects were then injected with 30 milligrams of methamphetamine and asked to rate the high they experienced on a scale of 1 to 10, with 10 being the most intense imaginable. The users given doses of bupropion reported experiencing a significantly reduced high of, on average, 3 out of 10, compared to 5 out of 10 prior to the treatment. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse; Depression
Link ID: 8229 - Posted: 06.24.2010

By DENISE GRADY Within seconds, they could actually feel their waists begin to shrink. It would have been a great advance in the world of weight loss - if only it had been real. But the shrinking feeling was just an illusion, created by scientists who wanted to study how the brain creates body image, people's perceptions of their own size and shape. The researchers, led by Dr. H. Henrik Ehrsson of University College London, fooled 17 people into feeling as if they were getting skinnier by outfitting them with gadgets that stimulated a tendon in each wrist to create the false sensation that both hands were moving inward. The subjects wore blindfolds and placed their hands at their waists, and then the stimulators were turned on, while an M.R.I. scanner measured activity in different parts of the brain. For the subjects, the feeling that their wrists were flexing inward was so powerful that they felt their waists had to be getting smaller. Their study is published today in the journal Public Library of Science Biology (www.plosbiology.org). The technique is a variation on the Pinocchio illusion, an experiment first done - and named - in 1988 by another researcher, James R. Lackner of Brandeis University, in which stimulation of wrist tendons convinced blindfolded people who were touching their noses that their noses were growing. Copyright 2005 The New York Times Company

Keyword: Obesity; Anorexia & Bulimia
Link ID: 8228 - Posted: 11.29.2005

By GINA KOLATA Christina Koenig found out she had breast cancer on a Friday afternoon. She was just 39 years old. On Monday, she thought she knew why the cancer had struck. "I went in and talked to a team of medical professionals who ultimately performed a lumpectomy, and I said, 'How long has this been there?' They said, 'Five to ten years.' And immediately, my mind jumped to: 'Well, I did go through a divorce. I did have stress.' " Ms. Koenig, who lives in Chicago, was divorced four years before her cancer was diagnosed. Was it just a coincidence, she wondered? Now, four years later, she still wonders. So do many other women who get breast cancer. Ms. Koenig now works for Y-ME National Breast Cancer Organization, which gets 40,000 calls a year on its hot line. Over and over, she says, women ask, Did stress cause their cancer by weakening their immune system and allowing a tumor to grow? Copyright 2005 The New York Times Company

Keyword: Stress
Link ID: 8227 - Posted: 11.29.2005

Keay Davidson, Chronicle Science Writer Insects were the world's first aviators, and to this day their evolutionary descendants perform aerial stunts more dashing than the Blue Angels: They zip past your eyes like meteors, then hover like helicopters over flowers, then vanish out of sight before you can swat them. Scientifically speaking, insect flight was shrouded in mystery for much of the 20th century and even now is haunted by enigmas. Studies have shown how insects fly by frantically flapping their wings and taking advantage of physical forces too microscopic to be exploited by airplanes. Now scientists are beginning to investigate how insects' brains, although extremely tiny, can manage the incredibly complex motions required for them to stay aloft. Traditionally, scientists assumed that the basic physics of insect flight resembled the basic physics of human aviation. For example, there's an urban legend that many decades ago, scientists analyzed the plump bodies and stubby wings of bumblebees and concluded they were too heavy to fly. Over the years, during repeated retellings of this story in schoolyards and barrooms, it acquired a punch line: "But bees don't know they can't fly, so they fly anyway." ©2005 San Francisco Chronicle

Keyword: Miscellaneous
Link ID: 8226 - Posted: 06.24.2010

Feeling thin or fat is an illusion constructed in the brain, according to a new study published in the journal Public Library of Science Biology. The collaborative study led by UCL (University College London) used a trick called the Pinocchio illusion to scan people's brains while they experienced the sensation that their waists were shrinking. The study reveals which parts of the brain are involved in body image and may shed some light on anorexia and body dysmorphic disorder, where sufferers are overly concerned by a small or imagined defect in their body, and frequently overestimate or underestimate their actual body size. The study, led by Dr Henrik Ehrsson of the UCL Institute of Neurology, used the Pinocchio illusion in combination with functional magnetic resonance imaging to study volunteers' brains. For each volunteer, a vibrating device was placed on their wrist to stimulate the tendon and create the sensation that the joint was flexing, even though it remained stationary. With their hand touching their waist, volunteers felt their wrists bending into their body, creating the illusion that their waists were shrinking. During the tendon exercise, all 17 participants felt that their waist had shrunk by up to 28 per cent. The researchers found high levels of activity in the posterior parietal cortex, an area of the brain that integrates sensory information from different parts of the body. Volunteers who reported the strongest shrinking sensation also showed the strongest activity in this area of the brain.

Keyword: Anorexia & Bulimia
Link ID: 8225 - Posted: 11.29.2005

Most people with a rare type of dementia called primary progressive aphasia (PPA) have a specific combination of prion gene variants, a new study shows. The study is the first to link the prion protein gene to this disorder. It was funded in part by the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health (NIH), and appears in the December 2005 issue of the Annals of Neurology.[1] The researchers, led by James A. Mastrianni, M.D., Ph.D., of the University of Chicago, also looked at the prion protein gene in people with Alzheimer's disease and amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease) and did not find any association with specific gene variants in those disorders. PPA is classified as a type of frontotemporal dementia because of the pattern of brain degeneration it causes. The primary symptoms of the disease are problems speaking or understanding speech, and these problems gradually get worse over time. People with PPA also may develop difficulty with math. Most other functions remain normal for at least two years after the language symptoms appear, but the disease may eventually cause other changes, such as problems with memory, reasoning, and spatial abilities. While PPA sometimes runs in families, it has never before been linked to variations in a specific gene.

Keyword: Prions; Language
Link ID: 8224 - Posted: 11.29.2005

Andreas von Bubnoff Having too many males around can be bad news for lizards. Scientists have found that an excess of males can cause a small population of several dozen lizards to shrink because females are subjected to more male aggression during mating attempts, which reduces their survival and fertility. If the finding applies generally, removing excess males could be a useful tactic to save small, isolated populations of endangered species, the scientists say. Male aggression during sex occurs in many species. The male red-sided garter snake (Thamnophis sirtalis parietalis), for example, sometimes suffocates his partner during copulation. But this is the first study showing the effects this can have on population size, says Xavier Lambin, a behavioural ecologist at the University of Aberdeen who is not connected to the study. "Such effects have been speculated but not demonstrated before," Lambin says. The researchers monitored the reproduction and survival of two groups of common lizards (Lacerta vivipara) kept in enclosures in a meadow that were covered by nets to stop the lizards being picked off by birds.

Keyword: Aggression; Sexual Behavior
Link ID: 8223 - Posted: 11.29.2005

People suffering generalised social phobia experience increased brain activity when confronted with threatening faces or frightening social situations, new research shows. The finding could help identify how severe a person's generalised social phobia is and measure the effectiveness of pharmacological and psychological treatments for the condition. Up to one million Australians suffer from social phobia at any one time, making it the most common anxiety disorder, and the third most common psychiatric disorder after depression and alcohol dependence. People with generalised social phobia experience heightened anxiety during potential or perceived threatening social situations. They generally avoid eye contact and fear any interpersonal situation. The research, to be published in the journal Biological Psychiatry, was conducted by an international team of researchers, including Associate Professor Pradeep Nathan from Monash University's Centre for Brain and Behaviour and the Department of Physiology. The researchers found that the area of the brain called the amygdala becomes increasingly hyperactive when patients look at threatening, angry, disgusted or fearful faces. Further, they found that the increased response in the amygdala correlated with the patients' level of social phobia symptoms.

Keyword: Emotions; Autism
Link ID: 8222 - Posted: 11.29.2005

The relationship between the size of a brain structure and the ability to recover from traumatic experiences also may influence overall personality type, according to a study from Massachusetts General Hospital (MGH) researchers. In a followup to earlier findings that an area of the brain called the medial orbitofrontal cortex (mOFC) appears thicker in those who can better control their emotional response to unpleasant memories, the investigators found that study participants who exhibited better fear inhibition also score higher in measures of extraversion – an energetic, outgoing personality. The report appears in the Nov. 28 issue of NeuroReport. "Some studies have demonstrated links between extraversion or the trait of neuroticism and the overall activity of brain regions that include the mOFC. But this is the first time anyone has looked at the potential relation of both brain structure and fear extinction to personality traits," says Mohammed Milad, PhD, of the MGH Department of Psychiatry, a co-lead author of the study. Most individuals initially respond with physical and emotional distress to situations that bring back memories of traumatic events, but such responses usually diminish over time, as the situations are repeated without unpleasant occurrences. The ability to suppress those negative responses is called "extinction memory," and its deficiency may lead to anxiety disorders such as post-traumatic stress disorder. In their previous study, the MGH team focused on the ventromedial prefrontal cortex – an area on the lower surface of the brain that includes the mOFC and is believed to inhibit the activity of the amygdala, a structure known to be involved with fear. The current report combined the data analyzed in that study – published in the July 26, 2005, Proceedings of the National Academy of Science – with the results from a standard personality test.

Keyword: Emotions
Link ID: 8221 - Posted: 06.24.2010

Swimming with dolphins appears to help alleviate mild to moderate depression, researchers have found. A University of Leicester team tested the effect of regular swimming sessions with dolphins on 15 depressed people in a study carried out in Honduras. They found that symptoms improved more among this group than among another 15 who swam in the same area - but did not interact with dolphins. The study is published in the British Medical Journal. All the volunteers who took part in the trial stopped taking antidepressant drugs or undergoing psychotherapy at least four weeks beforehand. Half the volunteers swam and snorkelled around dolphins for one hour a day over a two-week period. The others took part in the same activities, but without dolphins around. Two weeks later, both groups showed improved mental health, but especially so among patients who had been swimming with the dolphins. The researchers say dolphins' aesthetic value, and the emotions raised by the interaction may have healing properties. Some have speculated that the ultrasound emitted by dolphins as part of their echolocation system may have a beneficial effect. The Leicester team believe that using animals in this way could be a productive way to treat depression and other psychiatric illnesses. (C)BBC

Keyword: Depression
Link ID: 8220 - Posted: 11.25.2005

Gerontologist Stephen Kritchevsky says differences in our genes may explain why some of us reap the benefits of exercise more than others — especially as we age. This may offer new opportunities to explore treatments to help older adults maintain their mobility. "Even if you exercise, it doesn't guarantee that you will maintain function," says Kritchevsky, from Wake Forest University Baptist Medical Center. "There are other things going on." As part of much larger study to investigate the functional health of older people, called the Health ABC Study, Kritchevsky and his research team followed the health and activity levels of more than 3,000 people in their 70's over four years. "We asked them what kinds of physical activity they did over the past two weeks and took a blood sample to find out kind of what genotype that they had," he explains. "And then we talked to this group every six months over the next four years." Regular exercise helped most of them gain or maintain their mobility. Kritchevsky says, "People who were physically active when we first talked with them maintained maintain walking ability much better than the people who weren't physically active." However, a small percentage developed mobility problems in spite of exercising. It turned out they had a variation in a gene called ACE (angiotensin converting enzyme), what the researchers refer to as a difference in the person's genetic make-up, or genotype. © ScienCentral, 2000-2005.

Keyword: Genes & Behavior
Link ID: 8219 - Posted: 06.24.2010

Ben Harder When a groggy reporter complaining of difficulties falling asleep recently visited a doctor in Washington, D.C., the physician's quick solution was to offer her a free sample of a drug called Rozerem (ramelteon). "What do you know about the drug?" the reporter queried, as reporters are apt to do. Noting that the medicine had been approved only a few months earlier, the doctor confessed to knowing next to nothing about it. Since 2000, prescriptions for sleeping pills have increased in all age groups, nearly doubling for children and young adults. Last year, doctors across the country doled out millions of scripts for Ambien (zolpidem) and its relatives in the group known as hypnotic drugs. Doctors also prescribed unofficial sleep aids, including antidepressants and anti-epileptic drugs, to slumber-deprived patients. The options are still increasing. In the past year, several new drugs targeting insomnia reached the market. One was a variation on an older medication; others took advantage of new insights into sleep biology. In addition to the novel drug Rozerem (ramelteon), the Food and Drug Administration approved the hypnotic drugs Lunesta (eszopiclone) and a new, slow-release formulation of zolpidem called Ambien CR. At least one other hypnotic compound, indiplon, could appear in pharmacies next year. A few novel anti-insomnia drugs are currently being tested. Copyright ©2005 Science Service.

Keyword: Sleep
Link ID: 8218 - Posted: 06.24.2010

By Larry O'Hanlon, Discovery News —A mysterious underwater "boing" heard for 50 years by marine scientists and naval mariners in the North Pacific Ocean has finally been traced to breeding minke whales. The discovery comes as a bit of a surprise, since it's usually not so hard to link a sound caught by hydrophones to a marine mammal. That's because unlike fish, marine mammals have to come up for air and can be spotted on the surface. "The common thinking was that it was being made by a large fish,” said Jay Barlow of the National Oceanic and Atmospheric Administration's Southwest Fisheries Science Center in La Jolla, Calif. Barlow was among the scientists onboard a research vessel near the Hawaiian Islands in 2002 that made the minke-boing connection. A report on the discovery has just been published by Barlow and his colleague Shannon Rankin in the November issue of the Journal of the Acoustical Society. Copyright © 2005 Discovery Communications Inc.

Keyword: Hearing; Sexual Behavior
Link ID: 8217 - Posted: 06.24.2010

In an important new study from the forthcoming Quarterly Review of Biology, biologists from Binghamton University explore the evolution of two distinct types of laughter – laughter which is stimulus-driven and laughter which is self-generated and strategic. "Laughter that occurs during everyday social interaction in response to banal comments and humorless conversation is now being studied," write Matthew Gervais and David Sloan Wilson. "The unstated issue is whether such laughter is similar in kind to laughter following from humor." Using empirical evidence from across disciplines, including theory and data from work on mirror neurons, evolutionary psychology, and multilevel selection theory, the researchers detail the evolutionary trajectory of laughter over the last 7 million years. Evolutionarily elaborated from ape play-panting sometime between 4 million years ago and 2 million years ago, laughter arising from non-serious social incongruity promoted community play during fleeting periods of safety. Such non-serious social incongruity, it is argued, is the evolutionary precursor to humor as we know it.

Keyword: Emotions; Evolution
Link ID: 8216 - Posted: 06.24.2010