It was hailed as the "trust" hormone, then the "mind-reading" hormone. Now it seems oxytocin may also help people with social phobia to interact. Markus Heinrichs at the University of Zurich, Switzerland, and colleagues are studying 70 people with generalised social phobia, characterised by overwhelming anxiety and self-consciousness in social situations. Half an hour before undergoing standard cognitive behavioural therapy, which is designed to alter negative thoughts and behaviour, the patients were given a dose of oxytocin by nasal spray. Preliminary results suggest oxytocin improved their readiness to interact in role-playing and their confidence in tackling social challenges outside the sessions, says Heinrichs, who will present his results at the World Congress of Neuroscience in Melbourne, Australia, this week. In a separate study, Heinrichs and colleagues report that oxytocin reduces the response of the amygdala - a brain region involved in the fear response - to pictures of fearful, happy or angry faces (Biological Psychiatry, DOI: 10.1016/j.biopsych.2007.03.025). This may explain why patients are more ready to engage in social situations, Heinrichs believes. © Copyright Reed Business Information Ltd

Keyword: Hormones & Behavior; Emotions
Link ID: 10500 - Posted: 06.24.2010

By DAVID TULLER For decades, people suffering from chronic fatigue syndrome have struggled to convince doctors, employers, friends and even family members that they were not imagining their debilitating symptoms. Skeptics called the illness “yuppie flu” and “shirker syndrome.” But the syndrome is now finally gaining some official respect. The Centers for Disease Control and Prevention, which in 1999 acknowledged that it had diverted millions of dollars allocated by Congress for chronic fatigue syndrome research to other programs, has released studies that linked the condition to genetic mutations and abnormalities in gene expression involved in key physiological processes. The centers have also sponsored a $6 million public awareness campaign about the illness. And last month, the C.D.C. released survey data suggesting that the prevalence of the syndrome is far higher than previously thought, although these findings have stirred controversy among patients and scientists. Some scientists and many patients remain highly critical of the C.D.C.’s record on chronic fatigue syndrome, or C.F.S. But nearly everyone now agrees that the syndrome is real. “People with C.F.S. are as sick and as functionally impaired as someone with AIDS, with breast cancer, with chronic obstructive pulmonary disease,” said Dr. William Reeves, the lead expert on the illness at the C.D.C., who helped expose the centers’ misuse of chronic fatigue financing. Copyright 2007 The New York Times Company

Keyword: Neuroimmunology; Stress
Link ID: 10499 - Posted: 06.24.2010

By NICHOLAS BAKALAR Certain kinds of carbohydrates may play a role in the development of age-related macular degeneration, an incurable degenerative eye disease that is a leading cause of blindness in older adults. A new study has found that eating carbohydrate-rich food with a high glycemic index — a measure of a food’s potential to raise blood glucose levels — is associated with the development of the disorder. The glycemic index is a measure of how fast carbohydrates are metabolized — the faster they are broken down into glucose, the higher the glycemic index. Simple carbohydrates, like those in cakes and cookies, cheese pizza, white bread or other foods sweetened with sugar or corn syrup, are quickly metabolized by the cells, while the complex carbohydrates in brown rice, barley and many other vegetables are broken down more slowly. Heavy consumption of foods with a high glycemic index has been implicated in the development of diabetes, cardiovascular disease and some cancers, according to background information in the paper, which appears in the July issue of The American Journal of Clinical Nutrition. The researchers examined 4,099 people ages 55 to 80 enrolled in a larger long-term study of eye health. Each participant had 20/32 vision in at least one eye, and the lens of the eye had to be clear enough to allow good photographs that could be used to diagnose macular degeneration. Copyright 2007 The New York Times Company

Keyword: Vision
Link ID: 10498 - Posted: 06.24.2010

Researchers say they may have worked out why the obese are more prone to asthma than those of normal weight. The link between the two conditions is well-established, but the relationship is ill-understood. Now scientists at King's College London say they have pinned down a protein which contributes to inflammation of the lungs as well as increasing hunger. The study in the Proceedings of the National Academy of Sciences said further research was now needed. The researchers investigated molecules produced by Th2 cells - specialised cells belonging to the immune system which can inflame the lungs and contribute to the development of asthma. But these cells also produce a protein known as PMCH which is known to increase appetite. "These findings may provide a mechanistic link between allergic inflammation, asthma and obesity," the researchers wrote. Several European and American studies have found a link between obesity and asthma which cannot be explained by weight gain brought on by the inactivity asthma encourages. In many cases, the obesity precedes the asthma. One study of 330,000 patients published earlier this year found that for every normal weight person with asthma, there were 1.5 who were overweight or obese. The latter category effectively ran a 50% greater risk of developing the condition. (C)BBC

Keyword: Obesity; Neuroimmunology
Link ID: 10497 - Posted: 07.17.2007

Heidi Ledford Getting sick often means getting tired too. Now researchers have tracked down how the chemical responsible for such drowsiness works. The culprit is a small protein called tumour necrosis factor alpha (TNF-alpha), named for its anti-tumour properties. This compound was known to trigger inflammation in response to infection and some chronic diseases such as rheumatoid arthritis and multiple sclerosis. And it was known to be linked — somehow — to fatigue. Cancer patients treated with TNF-alpha sometimes report severe lethargy, for example. And patients with a sleep disorder called sleep apnea sometimes report less daytime sleepiness after receiving a drug that interferes with TNF-alpha. But precisely how the protein was affecting sleep habits was unclear. Thomas Birchler, an immunologist at the University Hospital of Zurich in Switzerland, and his colleagues administered TNF-alpha to mice and then monitored the expression of genes involved in the biological clock, the internal timekeeper that tells us when to go to sleep and when to wake up. They found that the genes were expressed in their normal rhythm, rising and falling at designated points during the day. But the overall level of expression of some of these genes was reduced in mice that received the drug. "The oscillations were still in rhythm," says Birchler. "But the output of the clock genes was much reduced." © 2006 Nature Publishing Group

Keyword: Sleep; Neuroimmunology
Link ID: 10496 - Posted: 06.24.2010

Louis Buckley It seems that some chimps surprisingly use less energy walking on two feet than they do loping around on all four limbs. The researchers who discovered the expert walking ability of one chimp say it may help to explain how the earliest humans adapted to standing upright. Chimpanzees normally move about on all fours in a gait known as a 'knucklewalk', says David Raichlen from the University of Arizona in Tucson. "But they can also walk on two legs — when they're carrying things, reaching for fruit, that kind of thing." Raichlen trained five adult chimps to amble on a treadmill using both kinds of locomotion, and he also roped in four humans to strut their stuff at a variety of different speeds. The researchers then measured the amount of oxygen used in each case.1 As expected, chimps were significantly less efficient at walking than humans, using up 75% more energy, irrespective of whether they were walking on two legs or four. This is mainly down to the fact that humans walk using relatively straight legs. This means they can propel themselves along by swinging their rigid appendages, using a minimal amount of muscle. Chimps, on the other hand, generally walk with their knees and hips flexed. ©2007 Nature Publishing Group

Keyword: Evolution
Link ID: 10495 - Posted: 06.24.2010

Colin Barras It used to be easy to separate man from beast. Then we realised animals, too, can experience sophisticated emotions and communicate through language. But there is one thing that is beyond even our closest relatives, chimpanzees. And that is the ability to be spiteful. Keith Jensen and his team at the Max Planck Institute for Evolutionary Anthropology at Leipzig, Germany, conducted experiments in which they placed a food-laden table in front of a caged chimp. Attached to the table was a string the chimp could pull to collapse the table. The chimp resisted the urge to pull the string as long as the food was within its reach. But when the researchers moved the food to the opposite side of the table, the frustrated chimp collapsed the table in 30% of the trials. In a second experiment, the researchers placed a second chimp in a cage at the opposite side of the table. Moving the food across the table now benefited the second chimp at the cost of the first. If the first chimp wanted to be spiteful, it could simply collapse the table and prevent its rival from feeding. But the chimps tested merely showed the same level of frustration as before, collapsing the table 30% of the time. But if the second chimp attempted to move the food closer to itself, by pulling a string of its own, the first chimp reacted angrily, collapsing the table 50% of the time. © Copyright Reed Business Information Ltd.

Keyword: Emotions; Evolution
Link ID: 10494 - Posted: 06.24.2010

by Virginia Hughes • The humpback whale is known as the gregarious, singing "gentle giant" of the sea. But the herring it inventively preys upon—one whale in a gang blows "air bubble nets" around a school of fish while another screams until the poor things are scared to the surface—would probably disagree with this assessment. In any case, the auditory and communicative behaviors within groups of humpbacks reveal remarkable intelligence. However, since whale specimens are rare—either harvested from beached whales or sick aquarium residents—scientists know only the basics of their brain surface anatomy and are virtually ignorant about what goes on underneath. But last summer, neuroscientists from Mount Sinai School of Medicine got their hands on one of these rare brain samples and studied it. Now they've published a thorough morphological analysis of the humpback brain, and have compared it to a host of other species. Their study, published in the Nov. 27 early online edition of the journal The Anatomical Record, reveals that the humpback brain contains many anatomical curiosities, including one type of neuron involved in high-level cognitive functions previously thought to be unique to primates. "Methodologically, it's a beautifully done study, and the results are really stunning," said neuroscientist Lori Marino of Emory University, who was not involved in the research. "[The presence of these neurons] tells us that these are animals with possibly a very sophisticated sense of social cognition." © Copyright 2005-2007 Seed Media Group, LLC

Keyword: Evolution
Link ID: 10493 - Posted: 06.24.2010

Mental illness poses a particular challenge for medical researchers trying to understand what is going on in patients' brains. Exploratory surgery is a tough sell. Instead, researchers turn to animal models of psychiatric ills, bearing in mind that a mouse will never show signs of hypochondria and a fruit fly will never buzz off to Vegas for a gambling addiction. Still, researchers have made headway against a lot of psychiatric ills by experimenting on animals, and a neuroengineering team led by Stanford University's Karl Deisseroth reports on a possible answer to one of the mysteries behind depression. "Depression raises all kinds of questions," Deisseroth says. "It has all sorts of symptoms and responds to a variety of drugs that act in different ways." Almost 15 million people nationwide suffer from a "major depressive disorder," according to the federal National Institute of Mental Health. The researchers looked at a rat known for exhibiting a symptom of depression — hopelessness. "They give up on tasks easily," he says. The same rats respond to treatment with fluoxetine, an antidepressant commonly given to people as well. The team treated some of their rats to 5-to-7 weeks of stress, such as changing their sleeping and feeding schedules, tilting their cages and using strobe lights. Some of the rats received antidepressants and some didn't. Copyright 2007 USA TODAY,

Keyword: Depression
Link ID: 10492 - Posted: 06.24.2010

Blocking a molecule in the brain may "cure" post-traumatic stress disorder, according to US researchers. They showed that inhibiting a specific enzyme removed fear in mice and report to journal Nature Neuroscience that the finding may lead to new treatments. Around a third of people may suffer PTSD after an exceptionally traumatic event, such as a terrorist attack or a natural disaster. Experts said it was early days but the findings were worth exploring further. There is currently no treatment for PTSD although antidepressants and sleeping pills can help with the symptoms, which include flashbacks, anger, anxiety and depression. Professor Li-Huei Tsai and colleagues in the Brain and Cognitive Sciences Department at MIT looked at the effects of an enzyme called Cdk5 in the brains of genetically engineered mice which had been given mild foot shocks. When re-exposed to the same environment but without the shocks, mice in whom the researchers had increased levels of Cdk5 activity had difficulty letting go - or extinguishing - the memory of the foot shock and continued to freeze in fear. But in mice whose Cdk5 activity was blocked, the bad memory of the shocks disappeared when the mice learned that they no longer needed to fear the environment where the foot shocks had occurred. The enzyme activity was modified in the hippocampus - the brain's centre for storing memories. (C)BBC

Keyword: Stress; Learning & Memory
Link ID: 10491 - Posted: 07.16.2007

Scientists have discovered a protein which may help to slow, or even reverse symptoms of Parkinson's disease. Parkinson's destroys nerve cells that produce the brain chemical dopamine, causing movement and balance problems. Finnish researchers found the new molecule can prevent degeneration of these cells - and help damaged cells start to recover. Their paper, featured in Nature, showed symptoms eased in rats given injections of the protein. Current anti-Parkinson's drugs do not stop nerve cells from degenerating and dying, and their effects can be patchy and short-lived. The researchers, from the University of Helsinki, believe the new molecule - dubbed conserved dopamine neurotrophic factor (CDNF) - has great potential as a treatment. Previous research has centred on another protein - GDNF - which some research had suggested could improve symptoms in Parkinson's patients. However, other studies have thrown doubt over the effect of the protein - and raised serious safety issues. The Helsinki team decided to search for related proteins - known as growth factors - which worked in a similar way, but were likely to be better tolerated. They found that CDNF, unlike other similar growth factors, was specific to brain nerve cells. Experiments were carried out on rats bred to show symptoms similar to Parkinson's. In tests, CDNF protected 96% of nerve cells in the brains of the animals from degeneration. (C)BBC

Keyword: Parkinsons
Link ID: 10490 - Posted: 07.14.2007

Kavita Mishra, Chronicle Staff Writer Want to forget something? Just let your brain know. New research suggests that people can push out memories, even highly emotional ones, simply by deciding to do so. The researchers believe the new findings will help scientists understand disorders like post-traumatic stress disorder and obsessive-compulsive disorder, in which the brain's mechanism of suppressing unwanted memories may be dysfunctional, said lead author Brendan Depue, a graduate student in neuroscience and clinical psychology at the University of Colorado at Boulder. But many experts are wary of linking the findings -- published today in the online journal Science -- to debilitating disorders like PTSD. They believe the mind developed to actively forget some memories to keep from cluttering the brain with unpleasant memories and irrelevant information, like unnecessary phone numbers. But highly emotional memories may never be forgotten. "We have these mechanisms to try to stamp out and suppress these things when we want to try to avoid uncomfortable thoughts. On the other hand, we do know that very serious emotional memories are, in general, very remembered," UC Berkeley psychologist Art Shimamura said. Stanford psychologist Anthony Wagner said the findings help explain how the brain works to forget some things and not others. Specific areas of the brain are used in order to help us forget. © 2007 Hearst Communications Inc.

Keyword: Learning & Memory
Link ID: 10489 - Posted: 06.24.2010

By David Douglas NEW YORK (Reuters Health) - Examining the blood vessels in the retina of the eye may give a clue to the mental status of elderly people and their risk of developing dementia, researchers report. The presence of retinal damage, or retinopathy, "is a marker of early damage to the blood vessels in the brain, and is a harbinger of future stroke risk," senior investigator Dr. Tien Yin Wong of the University of Melbourne Centre for Eye Research, Australia, told Reuters Health. In order to see if retinopathy might also be linked to cognitive function and dementia, Wong and colleagues studied retinal photographs of 2211 people aged 69 to 97 years. More than half of them had hypertension, i.e., high blood pressure. After adjusting for factors such as age, diabetes, and smoking status, subjects with retinopathy had lower scores on a standard test of cognitive status than those without (39 versus 41), the team reports in the medical journal Stroke In subjects with high blood pressure, retinopathy doubled the likelihood of having dementia. No such relationship was seen in those without high blood pressure. © 1996-2007 Scientific American, Inc

Keyword: Alzheimers; Vision
Link ID: 10488 - Posted: 06.24.2010

Children with Fragile X Syndrome – the most common, inherited type of mental retardation – have delayed learning and language, poor coordination and repetitive behaviors. Now researchers at MIT have hope of reversing those symptoms after a successful study in mice. Mansuo Hayashi, lead researcher of the study, explains why a treatment is needed. "With the modern human genetic diagnosis, I think we could identify the genetic disorders prior to birth, but in many cases, with even with the advanced technology, the abnormality won't show up until after birth. … Therefore it's important to find a drug that will treat or delay the symptoms after the symptom appear." The brain of a Fragile X Child is like an inattentive gardener, letting too many bushy spines grow on brain cells. Normal brains prune these spines to keep the cells' connections strong. The abundance of weak connections in Fragile X causes a kind of static in brain signals. At MIT's Picower Institute for Memory and Learning, Hayashi worked with mice that had the opposite problem of Fragile X: too little spine growths on neurons due to inactivity of a chemical in the brain called PAK. The PAK enzyme controls the growth of neurons in the brain. She decided to breed these mice with Fragile X mice to see if some of the offspring would have normal brains. But Fragile X affects the brain as it grows, and the PAK inhibitor doesn't activate until the mice are several weeks old. Meaning that for it to work, it would have to reverse structural abnormalities in the brain, something that has never been observed. © ScienCentral, 2000-2007.

Keyword: Development of the Brain
Link ID: 10487 - Posted: 06.24.2010

By Benjamin Lester Monkeys imitate what they see, but so do humans, only more discreetly. Whether any muscles actually flex, our brains fire up the same pathways needed to perform any action we observe another person perform. But new work on disabled volunteers indicates that the brain instead activates alternate circuits when faced with an action its body cannot physically copy. The research suggests that the brain's motor system may be wired to work toward a goal rather than just duplicating a movement. Every time you watch someone press a computer key or pick up a cup, regions of your brain unconsciously respond, mapping what you see onto the motor pathways you would use to carry out that same motion. Researchers believe that this so-called mirror neuron system, which consists of a subclass of motor neurons, is critical to learning new behaviors, and perhaps for developing skills like recognizing facial expressions. But neuroscientists have long wondered how the brain reacts if the body lacks the ability to replicate the action. In a study reported 12 July in Current Biology, a team from the Netherlands, Italy, and France showed videos of hands performing simple actions, like grasping a cup, to 16 "normal" people and two aplasic people born without hands or arms. While the volunteers watched the video, the researchers spied on their brain activity using MRI. © 2007 American Association for the Advancement of Science

Keyword: Brain imaging
Link ID: 10486 - Posted: 06.24.2010

Larry O'Hanlon, Discovery News — Giving a squirrel a big, sweet cookie can be a kind gesture, and now scientists have found it also encourages the critter to watch for predators. The conclusion, in a newly published study, has implications for other species, including the survival of those facing human-caused changes to their habitats. Most animals have two daily concerns: Getting food and not becoming food. Unfortunately, concentrating on one of those activities is almost always at the cost of the other. "These two things make you survive," said animal behavior researcher Joanna Makowska at the University of British Columbia and lead author of a paper on an experiment that revealed how squirrels juggle those needs in the July issue of Animal Behaviour. "Most animals can’t be very vigilant while eating," Makowska told Discovery News. To get a clearer picture of just how and when squirrels choose to focus on food or predators, she and her undergraduate professor at McGill University, Donald Kramer, created an experiment that put the squirrels to the test. They placed sunflower seeds inside a two-and-a-half-foot high frame that blocked their peripheral views of the urban park in which they lived. © 2007 Discovery Communications

Keyword: Attention
Link ID: 10485 - Posted: 06.24.2010

Brian Vastag Call it a flimsy silver lining to a noxious blue cloud: Long-term smokers have half the risk of Parkinson's disease that nonsmokers do, according to a new report. In 12,000 people studied, those who smoked the most—the equivalent of at least a pack a day for 60 years—had the lowest risk. And after smokers stubbed out their last butts, the protective effect faded. Cigarette, cigar, and pipe smoking appear to offer similar anti-Parkinson's benefits, according to the report in the July Archives of Neurology. Author Beate Ritz of the University of California, Los Angeles characterizes the amount of Parkinson's protection provided by smoking as moderate. "Never-smokers have about a twofold higher risk of Parkinson's disease than ever-smokers," she says. However, because Parkinson's disease is fairly rare—only about 60,000 new cases are diagnosed each year in the United States—and because smoking causes cancer and heart disease, "nobody would ever recommend smoking in order to prevent Parkinson's," Ritz emphasizes. ©2007 Science Service.

Keyword: Parkinsons; Drug Abuse
Link ID: 10484 - Posted: 06.24.2010

Kerri Smith People can will themselves to forget traumatic or emotional scenes, researchers have found. When the brain conducts such deletions, brain regions that process vision and emotion go quiet. Knowing that memories can be consciously suppressed, and the brain areas involved, could point to therapies for people who struggle to forget traumatic experiences, such as those with post-traumatic stress disorder or obsessive-compulsive disorder. Neuroscientist Brendan Depue, of the University of Colorado at Boulder, wanted to find out what goes wrong in the brains of sufferers of such conditions. Previous studies have shown that people can suppress memories of words. But to make the test relevant to traumatic memories, Depue's team included an emotional component. They showed volunteers pairs of pictures: one of a face, and one to evoke an emotional response — a car crash, or a wounded person. Once the subjects had learned to associate the image pairs, they were shown the faces alone, and either told to think of the associated picture or to try not to think about it. The subjects' brains were less active when they deliberately tried not to think of the associated picture, the team found. "It looks like these areas of the brain are being shut down," says Depue. ©2007 Nature Publishing Group

Keyword: Learning & Memory
Link ID: 10483 - Posted: 06.24.2010

Biomedical researcher Priti Kumar came to the United States to look for a cure for deadly encephalitis infections, which kill tens of thousands of people a year in her native India. She and her colleagues in the lab of Manjunath N. Swamy at Harvard's CBR Institute ended up finding a way to potentially treat virtually any brain disease. West Nile Virus encephalitis and Eastern Equine Encephalitis are among the many types of mosquito-spread encephalitis viruses that attack the brain. "There are no drugs existing for encephalitis in the world today," Kumar says. "What has been routinely commonly followed in all hospitals is that when a patient comes in with encephalitis, he is just put on something like supportive therapy and you wait for the immune system to kick back in, and the patient recovers if an immune system reaction to the virus is able to bring him out of the infection." Kumar's team was able to use RNA interference to develop a new kind of therapy against brain diseases like encephalitis. But there was still a big barrier to being able to use the drug in people-- the natural barrier called the blood-brain barrier, tightly-packed cells around the blood vessels that prevent molecules from passing from the bloodstream into the brain. © ScienCentral, 2000-2007.

Keyword: Miscellaneous
Link ID: 10482 - Posted: 06.24.2010

Being the life and soul of the party may cut your chances of a fatal heart or stroke, research suggests. A 30-year study by Chicago Northwestern University suggested shy or antisocial men were 50% more likely to die this way, compared with outgoing men. The Annals of Epidemiology study supports other work suggesting a link between personality and health. A British expert said lower social status may be the root cause of both shyness and poor health. The researchers tracked the health of more than 2,000 middle-aged men over three decades, until 60% of their subjects had died. The death certificates were matched with psychological questionnaires filled in at the start of the study to reveal the personality type of the man in question. The shyest group of men were 50% more likely to have died from heart attack or stroke than the group of most sociable men. When other information about the mens' lifestyles was analysed, no link to other known risk factors, such as smoking, drinking or obesity came to light - apparently ruling out the theory that shy or unsocial men might be dying because of unhealthy, couch potato behaviour. The researchers suggested that either that shy men are more stressed by new situations, or that the setting of their personality type is in some way linked to the part of the the brain that controls the smooth operation of the heart. Decades of research suggest there is only one personality type which is not linked to an increase risk of serious disease. Easy going people - so-called type "B" personalities - appear to be the healthiest. Type "A" personalities - driven workaholics prone to stress and anger, are more likely to suffer high blood pressure and heart disease, while Type "C" people, who suppress their feelings, have been connected to an increased risk of cancer.

Keyword: Stress; Emotions
Link ID: 10481 - Posted: 07.14.2007