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

SOME relatives of people with autism also display behaviours and brain differences associated with the condition, even though they themselves do not have it. This could make it easier to spot families at risk of having an autistic child. It could also help in the quest to identify the genetic and environmental triggers for the condition, though it seems these triggers might vary from country to country. Eric Peterson of the University of Colorado in Denver had compared an MRI study of the brains of 40 parents with autistic children to that of 40 age-matched controls. And he told the Society for Neuroscience annual meeting in Washington DC that the parents who had an autistic child shared several differences in brain structure with their offspring. Looking at the group averages, the differences in parents of the autistic children included an unexpected increase in the size of the motor cortex and basal ganglia, areas important for movement planning and imitation. The somatosensory cortex, neighbouring the motor cortex, by contrast, was smaller than average. This region is important for understanding social information such as facial expressions - one key skill that autistic people often lack. These parents also had reductions in the cerebellum, important for coordinating movement, and in a frontal region thought to be responsible for understanding the intentions and feelings of others - the so-called theory of mind area. © Copyright Reed Business Information Ltd.

Keyword: Autism; Genes & Behavior
Link ID: 8215 - Posted: 06.24.2010

Even if you could get more RAM for your brain, the extra storage probably wouldn't make it easier for you to find where you left your car keys. What may help, according to a discovery published Nov. 24 in the journal Nature, is a better bouncer – as in the type of bouncer who manages crowd control for nightclubs. The study by Edward Vogel, an assistant professor of cognitive neuroscience at the University of Oregon, is the first to demonstrate that awareness, or "visual working memory," depends on your ability to filter out irrelevant information. "Until now, it's been assumed that people with high capacity visual working memory had greater storage but actually, it's about the bouncer – a neural mechanism that controls what information gets into awareness," Vogel said. The findings turn upside down the popular concept that a person's memory capacity, which is strongly related to intelligence, is solely dependent upon the amount of information you can cram into your head at one time. These results have broad implications and may lead to developing more effective ways to optimize memory as well as improved diagnosis and treatment of cognitive deficits associated with attention deficit disorder and schizophrenia.

Keyword: Learning & Memory; Vision
Link ID: 8214 - Posted: 06.24.2010

Canadian scientists have developed some clever molecular trickery that is helping to reduce the drug cravings of addicted rats. One of the problems in addiction is that neurons in some parts of the brain lose glutamate receptors from the cell surface, and those receptors are important for communication between neurons. The researchers have sidestepped this problem by crafting a peptide that mimics a portion of the tail of the glutamate receptor and, once inside a neuron, serves as a decoy to prevent the loss of glutamate receptors. Yu Tian Wang and colleagues report their findings in the November 25, 2005, issue of the journal Science. In addicted rats, cell-to-cell communication is compromised as a result of certain long-term changes at the level of individual neurons. Their research has produced a targeted drug that tricks brain cells into preventing those changes. “We think this is a good candidate for a drug against addiction that has very few side effects,” said Wang, a neuroscientist . Although the initial studies are promising, Wang cautioned that the drug is in the early stages of development and is years away from testing in humans. During addiction to drugs, cells in the nucleus accumbens—a tiny ball of tissue deep in the brain involved in pleasure and motivation—miscommunicate. Normally, one neuron triggers activity in a neighbor by using neurotransmitters such as glutamate. “This is the 'go' signal,” said Wang. “The receiving cell uses glutamate receptors on its surface to listen to the signal. © 2005 Howard Hughes Medical Institute.

Keyword: Drug Abuse
Link ID: 8213 - Posted: 06.24.2010

By comparing foxes selected for tameness with others that have not been selected in this way, researchers have found evidence that dramatic behavioral and physiological changes accompanying tameness may be associated with only limited changes in gene activity in the brain. The work is reported by Elena Jazin and colleagues at Uppsala University, the Swedish University of Agricultural Sciences, and the Norwegian University of Life Science. The first step in the process of domestication in mammals is the selection for tame individuals that can adapt to life with humans and to frequent handling. To investigate the changes in gene activity that accompany tameness, in the present study the authors compared two groups of farm-raised silver foxes (Vulpes vulpes). One group derived from a long-standing domestication process in which farm-raised silver foxes have been selected for more than 40 generations for non-aggressive behavior toward men (see the related work of Brian Hare and colleagues, Current Biology 15:226–230). Another group of foxes was also farm raised but was not selected for tameness. The foxes selected for tameness were docile and friendly and showed developmental, morphological, and neurochemical changes similar to those observed in other domestic animals.

Keyword: Genes & Behavior; Evolution
Link ID: 8212 - Posted: 06.24.2010

A total of 25% of schizophrenics say they have stopped taking their medication because of adverse side effects, research has found. The charity Sane said this was leading to an increase in relapse rates and hospital re-admissions. Its survey found that 62% of respondents had not been told about side effects, including weight gain, drowsiness and restlessness. The charity is calling for better communication by health workers. The survey found that three-quarters of patients suffer from side effects, which can put them at greater risk of serious conditions such as diabetes and cardiovascular disease. Schizophrenia is the most common major psychiatric disorder and affects around one in 100 people in the UK. The condition is associated with a shorter life expectancy, although this is thought to be due to a number of factors, including reduced socio-economic status. The findings of the latest study echo previous research which found that one in 10 psychiatrists never proactively discussed long-term health risks associated with some treatments. Marjorie Wallace, chief executive of Sane, said: "It is appalling that so many patients are not being given information vital to understanding the impact of their treatment and in turn their ability to make decisions and help in their own recovery. (C)BBC

Keyword: Schizophrenia
Link ID: 8211 - Posted: 11.22.2005

(Philadelphia, PA) -- Using a novel application of an fMRI (functional magnetic resonance imaging) technique, researchers at the University of Pennsylvania School of Medicine have, for the first time, visualized the effects of everyday psychological stress in a healthy human brain. Their work, performed at Penn's Center for Functional Neuroimaging, provides a neuro-imaging marker of psychological stress -- which will pave the way for the development of improved strategies for preventing or correcting the long-term health consequences of chronic stress. The researchers' study appears in the November 21 online edition of Proceedings of the National Academy of Sciences. In the Penn study, researchers induced stress on healthy subjects by asking them to quickly tackle challenging mental exercises while being monitored for performance. During the fMRI scans, the researchers also recorded subjects' emotional responses -- such as stress, anxiety, and frustration -- and measured the corresponding changes in stress hormone and heart rate. Many subjects described themselves as being "flustered, distracted, rushed and upset" by the stress task. The results showed increased cerebral blood-flow during the "stress test" in the right anterior portion of the brain (prefrontal cortex) -- an area long associated with anxiety and depression. More interestingly, the increased cerebral blood-flow persisted even when the testing was complete. These results suggest a strong link between psychological stress and negative emotions. On the other hand, the prefrontal cortex is also associated with the ability to perform executive functions -- such as working memory and goal-oriented behavior -- that permit humans to adapt to environmental challenges and threats.

Keyword: Stress; Brain imaging
Link ID: 8210 - Posted: 11.22.2005

By DONALD G. McNEIL Jr. Gerard O'Donnell is a firefighter, so his snoring - which sounds like a chain saw fighting its way through 500 pounds of toffee - is a problem at work as well as at home. His girlfriend frequently gets up to sleep in her son's bed "just so she can get a few hours," he said. A New Treatment for Sleep Apnea At his Brooklyn firehouse, he stays up late, trying to be the last one into the bunkroom, "but they still bust my chops." His crew mates even added a box of nasal strips to one of their grocery runs. It didn't help. So last month, Mr. O'Donnell tried something new. Dr. Charles P. Kimmelman, a Manhattan otolaryngologist, injected three polyester braids into the back of his throat. The treatment, known as the pillar palatal implant system and patented by the Restore Medical Company of St. Paul, has been performed on about 9,000 Americans and 1,000 patients in Europe and Hong Kong. It has received publicity because it is faster, cheaper and far less painful than traditional snoring surgery. Copyright 2005 The New York Times Company

Keyword: Sleep
Link ID: 8209 - Posted: 11.22.2005

By SANDRA BLAKESLEE Hypnosis, with its long and checkered history in medicine and entertainment, is receiving some new respect from neuroscientists. Recent brain studies of people who are susceptible to suggestion indicate that when they act on the suggestions their brains show profound changes in how they process information. The suggestions, researchers report, literally change what people see, hear, feel and believe to be true. The new experiments, which used brain imaging, found that people who were hypnotized "saw" colors where there were none. Others lost the ability to make simple decisions. Some people looked at common English words and thought that they were gibberish. "The idea that perceptions can be manipulated by expectations" is fundamental to the study of cognition, said Michael I. Posner, an emeritus professor of neuroscience at the University of Oregon and expert on attention. "But now we're really getting at the mechanisms." Even with little understanding of how it works, hypnosis has been used in medicine since the 1950's to treat pain and, more recently, as a treatment for anxiety, depression, trauma, irritable bowel syndrome and eating disorders. Copyright 2005 The New York Times Company

Keyword: Attention
Link ID: 8208 - Posted: 11.22.2005

Keay Davidson, Chronicle Science Writer Seriously folks, scientists want to know what tickles people's funny bones, and they're looking into the brain to find out. At Stanford University, Professor Allan L. Reiss and his colleagues are using a brain-scanning technique in combination with "Bizarro" and "Far Side" cartoons to see if activity in the gray matter between the ears reveals whether men and women react differently to visual humor. At Dartmouth College in New Hampshire, students are laughing at the TV sitcoms "Seinfeld" and "The Simpsons" while being scanned by the same brain-scanning technique, known as functional magnetic resonance imaging or "fmri". Strange as such research might appear to laypeople, "humor is quite amenable to scientific study," says neuroscience Professor Gregory S. Berns of Emory University, who wasn't connected with either of the brain-scanning studies. Berns, who in a 2004 article for the journal Trends in Cognitive Sciences, wrote about Reiss' earlier studies of humor, said such studies must be conducted in the tightly controlled circumstances of labs like Reiss' because, as he noted with a chuckle, "we can't study people in a comedy club audience with fmri." In their lab, Reiss and his four Stanford colleagues found that on the average, males and females seem to be amused -- or not amused -- by the same kinds of cartoons. ©2005 San Francisco Chronicle

Keyword: Emotions; Sexual Behavior
Link ID: 8207 - Posted: 06.24.2010

KINGSTON, Ont. – Surprisingly, people with mild depression are actually more tuned into the feelings of others than those who aren’t depressed, a team of Queen’s psychologists has discovered. “This was quite unexpected because we tend to think that the opposite is true,” says lead researcher Kate Harkness. “For example, people with depression are more likely to have problems in a number of social areas.” The researchers were so taken aback by the findings, they decided to replicate the study with another group of participants. The second study produced the same results: People with mild symptoms of depression pay more attention to details of their social environment than those who are not depressed. Their report on what is known as “mental state decoding” – or identifying other people’s emotional states from social cues such as eye expressions – is published today in the international journal, Cognition and Emotion. Also on the research team from the Queen’s Psychology Department are Professors Mark Sabbagh and Jill Jacobson, and students Neeta Chowdrey and Tina Chen. Drs. Roumen Milev and Michela David at Providence Continuing Care Centre, Mental Health Services, collaborated on the study as well. ©Queen's University, 2005

Keyword: Depression
Link ID: 8206 - Posted: 06.24.2010

By Virginia Hughes Two new studies provide the strongest evidence yet that schizophrenia is a genetic disease and shed further light on how it progresses on a molecular level. The findings may lead to the design of better antipsychotic drugs, say the researchers. Many scientists have assumed that schizophrenia is caused by environmental influences, such as viral infections or psychological stress. But a genetic case for the disease was bolstered in 2000 when J. Kirsty Millar of the University of Edinburgh, United Kingdom, found that a number of Scottish schizophrenics shared a mutation in a gene called DISC1. Not all researchers were convinced of the gene's significance, however, because Millar's study was limited to a single family. Now two studies provide further evidence of DISC1's role in the development of schizophrenia. As reported online yesterday in Nature Cell Biology, Akira Sawa of Johns Hopkins University in Baltimore, Maryland, and colleagues disrupted DISC1 expression in the brains of mouse embryos using a technique called RNA interference. Compared to controls, the mice experienced a severe delay in the migration of neurons in their brains, leading to abnormal brain development. What's more, the neurons themselves were improperly oriented in a pattern that matched that seen in the brains of human schizophrenics. This is the first time DISC1 dysfunction has been linked to schizophreniclike abnormalities in living brain tissue, says Sawa. © 2005 American Association for the Advancement of Science.

Keyword: Schizophrenia; Genes & Behavior
Link ID: 8205 - Posted: 06.24.2010