By Michael Balter Being human has its pluses and minuses. Our cognitive powers are superior to that of other animals, and we can act consciously to alter our destinies. On the other hand, our highly evolved brains are prone to serious malfunctions such as mental illness and dementia. Now a team of neuroscientists has found that some of these blessings and curses might be linked to the same specialized neural circuits. In 1999, researchers discovered that the brains of humans and great apes such as chimpanzees and gorillas contain special elongated nerve cells called spindle neurons. These cells, also known as Von Economo neurons (VENs), are localized in two parts of the cerebral cortex known to be associated with social behavior, consciousness, and emotion. They are not found in other primates, although very recently they were discovered in some whales (ScienceNOW, 27 November). William Seeley, a neurologist at the University of California, San Francisco, and colleagues set out to see whether VENs play a role in a type of dementia that causes people to lose inhibition in social situations. People with frontotemporal dementia (FTD) engage in inappropriate and impulsive behavior and sometimes even carry out criminal acts such as shoplifting. The team looked at the brains of 7 deceased patients with FTD and compared them to 7 controls who had died of causes unrelated to the brain, as well as 5 patients diagnosed with Alzheimer's disease, a very different type of dementia that mainly affects memory. The researchers found that one of the two brain areas that contain VENs, the anterior cingulate cortex, looked very different in FTD patients: There was a 74% reduction in the number of VENs compared to controls. In contrast, Alzheimer's patients had only a small and statistically insignificant reduction, they report online today in Annals of Neurology. © 2006 American Association for the Advancement of Science

Keyword: Alzheimers; Attention
Link ID: 9791 - Posted: 06.24.2010

NEW YORK (Reuters Health) - Topamax, usually prescribed to prevent epileptic seizures, is also an effective treatment for so-called sleep-related eating disorder, according to a new study. Sleep-related eating disorder, or SRED, "is a behavioral disorder combining the repetitive nocturnal awakenings of a sleep disorder with the driven, compulsive eating of a daytime eating disorder," study author Dr. John W. Winkelman, of Harvard Medical School, Boston, writes in the Journal of Clinical Psychiatry. The disorder "is characterized by partial or full awakenings from sleep with compulsive eating, usually of high-calorie foods." Winkelman reviewed the cases of 30 patients with SRED who were treated with Topamax (known generically as topiramate) in a sleeping disorders clinic. Of the participants, 25 had at least one follow-up appointment. The average age of these 25 patients was 44 years, and three-quarters were female. SRED had started when the subjects were an average of 25 years old. Before starting topiramate, all the patients experienced nocturnal eating on a nightly basis, and most had multiple episodes of eating per night. After about 11 months of treatment, "17 (68%) of 25 patients were considered responders, 7 (28%) of 25 were unchanged, and 1 (4%) of 25 was worse," Dr. Winkelman reports. © 1996-2006 Scientific American, Inc.

Keyword: Sleep
Link ID: 9790 - Posted: 06.24.2010

Susan Milius Two female Komodo dragons in zoos have startled their keepers by laying viable eggs without any contribution from males. The world's largest lizard species had previously been observed to reproduce only in the usual mom-and-pop way, explains Kevin Buley of the Chester Zoo in England. So, he and the staff at the London Zoo were surprised when, at each institution, a female with no access to males managed to have offspring. Genetic tests have verified that each female was the sole parent of her clutch, Buley and his colleagues report in the Dec. 21 Nature. Solo moms have turned up in only 70 vertebrate species. Mammals never reproduce this way, according to the scientific literature. A few reptiles, amphibians, fish, and birds manage some variation on single-parent reproduction. The Komodo dragon "is certainly the largest," says Buley. Female Komodo dragons without males around have been known to lay infertile eggs. However, in May, one of the Chester Zoo's Komodo dragons laid a clutch that "looked really good," says Buley. "On a whim, we put them in an incubator." Three eggs collapsed, and when staff members opened them, "to our amazement, we found blood vessels and small embryos," he says. Flora, the Chester Zoo's new mom, had never been housed with a male. Buley sent tissue samples from Flora's embryos to the University of Liverpool. There, coauthor Phillip Watts and his colleagues found that although the embryos weren't exact replicas of the mother, only her genetic material had contributed to them. The doubling of sex chromosomes that occurs in this kind of asexual reproduction creates males among reptiles. ©2006 Science Service

Keyword: Sexual Behavior
Link ID: 9789 - Posted: 06.24.2010

Kerri Smith Researchers have recreated in a virtual world one of the most extreme social experiments ever performed in the real world. The results suggest that virtual environments could provide a way to explore human nature in ways that ethical concerns could make impossible to do for real. Mel Slater, who works jointly at the Catalan Polytechnic University in Barcelona, Spain, and at University College London, UK, and his colleagues set up a virtual version of an infamous experiment on obedience to authority. In the original experiment, conducted by Stanley Milgram in the 1960s, volunteers were told by an authority figure to deliver electric shocks to another person as punishment for incorrect answers to a test1. The other person wasn't really receiving the shocks, but the volunteers were tricked into thinking they were by shouts of pain and protest. Despite this feedback, some volunteers went on to deliver what would have been lethal shocks. Slater's volunteers did a similar experiment, but in an immersive virtual environment where they interacted with a virtual woman. This counters some of the ethical protests that have prevented Milgram's experiment from being repeated because the volunteers knew they would be interacting with a virtual woman and so, unlike Milgram's guinea-pigs, knew that nobody was being hurt. ©2006 Nature Publishing Group

Keyword: Aggression; Emotions
Link ID: 9788 - Posted: 06.24.2010

Scientists at Cardiff University have developed a potential treatment for Alzheimer's disease. Researchers say they have created an antibody which could block the production of brain chemicals linked to the debilitating disease. There is no known cure for Alzheimer's, which causes irreversible loss of brain function and memory. The disease affects one in 20 people aged over 65 and a fifth of all people over 80 in the UK. The results of the study show that it is possible to decrease production of the protein amyloid, which is believed to be the main cause of the disease. Deposits of amyloid build up in the brain, preventing it from functioning properly. The antibody will reduce this build-up, improving the patient's memory and quality of life, say researchers. Dr Kidd said: "Our results are highly encouraging at this stage. We believe that our approach could lead in time to a new therapy for this distressing and debilitating disease as it should prevent or reduce the irreversible deterioration of a patient's memory and other brain functions. This would also reduce the burden on carers, usually family members, who look after patients in the earlier stages of the disease." Dr Kidd said it was possible the antibody could be used as a preventative treatment for people with a family history of Alzheimer's. (C)BBC

Keyword: Alzheimers
Link ID: 9787 - Posted: 12.22.2006

By BENEDICT CAREY BUFFALO — In school he was as floppy and good-natured as a puppy, a boy who bear-hugged his friends, who was always in motion, who could fall off his chair repeatedly, as if he had no idea how to use one. This is the last in a series of articles about the increasing number of children whose problems are diagnosed as serious mental disorders. The earlier articles examined one family’s experience, the uncertainty of diagnosis, the use of combinations of psychiatric drugs and the transition to adulthood. "I don’t want him to look back and think the successes he’s had are all due to a drug," said Dawn Van De Wal, a mother of a child with attention deficit diagnosis. But at home, after run-ins with his parents, his exuberance could turn feral. From the exile of his room, Peter Popczynski would throw anything that could be launched — books, pencils, lamps, clothes, toys — scarring the walls of the family’s brick bungalow, and leaving some items to rattle down the hallway, like flotsam from a storm. The Popczynskis soon received a diagnosis for their son, attention-deficit hyperactivity disorder, or A.D.H.D., and were told that they could turn to a stimulant medication like Ritalin. Doctors have ample evidence that stimulants not only calm children physically but may also improve their school performance, at least for as long as they are on medication. Copyright 2006 The New York Times Company

Keyword: ADHD
Link ID: 9786 - Posted: 06.24.2010

EAST LANSING, Mich. — If you look at evolutionary biology as a big game of “Survivor,” it’s squirrels: one, spruce trees: zero. In the Dec. 22 edition of Science, Andrew McAdam, an assistant professor of fisheries and wildlife at Michigan State University, outlines how red squirrels have figured out a way around the elaborate ruse trees have used to protect their crops of tasty seeds. The remarkable part: The squirrels are divining the arrival of bumper crops of spruce cones months before the cones ever materialize and then betting on those crops with the most expensive evolutionary collateral – a second litter of pups. “We’ve been watching a co-evolutionary arms race where the trees and the squirrels are constantly trying to outwit each other,” McAdam said. “The trees’ strategy to outwit the squirrels has been documented, but now we’ve documented a counter strike by the squirrels.” The study, funded in part by the National Science Foundation and the Natural Sciences and Engineering Research Council of Canada, allows scientists to track the push and pull of evolution against an unforgiving struggle for survival. McAdam, Stan Boutin from the University of Alberta in Edmonton, Canada, and other international collaborators have been studying two different types of squirrels, which share the ‘red squirrel’ name but are only distantly related, in the forests of Canada, Belgium and Italy. The study has been going on for 20 years, with each squirrel carefully tracked. © 2006 Michigan State University Division of University Relations

Keyword: Evolution; Sexual Behavior
Link ID: 9785 - Posted: 06.24.2010

By Christopher Wanjek Magnet therapy is older than the holidays themselves. But don't let the millennia-old healing tradition fool you. That great suction force you might feel is just money leaving your wallet. Magnet therapy refers to healing with static magnets, the kind of basic magnet commonly found holding up notes and crayon artwork on a refrigerator. Products include magnetic belts, mattress pads, bracelets, bandages and shoe inserts. It's a $5 billion worldwide business, according to the National Center for Complementary and Alternative Medicine. Like many forms of alternative medicine, if magnet therapy works—and most studies find no positive effect or, at best, a statistically marginal effect attributed to the placebo effect—it would have to involve some novel biological mechanism. A top claim made by proponents is that magnets attract the iron in blood and improve blood flow, reducing pain. They only trouble with this theory is that iron in blood is bound to hemoglobin and is not attracted by magnets. You can test this, if you're brave, with a pinprick of blood. Then again, if blood were attracted to magnets, when you enter under the powerful magnets of an MRI machine, which are thousands of times stronger that so-called therapeutic magnets, you'd blow up. © 1999-2006 Imaginova Corp.

Keyword: Pain & Touch
Link ID: 9784 - Posted: 06.24.2010

CHAMPAIGN, Ill. -- A protein known primarily for its role in killing cells also plays a part in memory formation, researchers at the University of Illinois at Urbana-Champaign report. Their work exploring how zebra finches learn songs could have implications for treatment of neurodegenerative conditions such as dementia and Alzheimer's disease. When activated, the enzyme caspase-3 triggers a synaptic process essential for memory storage, according to Graham R. Huesmann and David F. Clayton of the department of cell and developmental biology and of the U. of I. Beckman Institute for Advanced Science and Technology. Their article, which appears in the Dec. 21 issue of the journal Neuron, describes their findings, which provide "the first direct evidence of a change in the availability of activated caspase-3 protein in the brain during the process of memory formation." Caspase-3 is best known for its role in a biochemical cascade that leads to apoptotic cell death. These new findings demonstrate that the enzyme acts differently under different conditions, and suggest that its regulation in the brain is more complex than previously thought. Huesmann and Clayton examined the brains of zebra finches after exposing the birds to tape recordings of the songs of other birds. They found an increase in the concentration of activated caspase-3 in post-synaptic sites of the auditory forebrain shortly after the birds were exposed to unfamiliar bird songs. Exposure to familiar songs caused no significant increase in the enzyme.

Keyword: Apoptosis; Learning & Memory
Link ID: 9783 - Posted: 12.22.2006

By Dan Ferber It's classic textbook ecology: To compete to have sex with attractive females, testosterone-loaded males grow antlers, sing complex songs, or wear silly hats to show their manliness. But in meerkats, it's the ladies who do the fighting. A new study reveals why and provides a better explanation for how females of some species evolved profoundly different traits than males. Females of many species risk and invest more to raise offspring, while males often try to impregnate a female and move on. As a result, ecologists had posited that males often evolve traits to help compete for access to healthy mates, while females choose males with traits that make for healthy offspring. But that theory did little to explain meerkats, which live in colonies of 3 to 50 animals, in which a single dominant female mates repeatedly with a single dominant male while the rest of the group cares for their pups. To better understand how dominant meerkats attain their status, behavioral ecologist Tim Clutton-Brock of the University of Cambridge, U.K., and his colleagues spent 12 years tracking the cuddly African mongoose on its home turf in the Kalahari desert. The researchers monitored 33 dominant females and 53 dominant males. Compared with dominant males, dominant females produced nearly twice as many pups that survived to adulthood. That's because on average, females stayed dominant for 32 months, nearly twice as long as dominant males. (And the longer they remained dominant, the more pups they had.) That means when they fight for dominance, female meerkats have a lot at stake. © 2006 American Association for the Advancement of Science.

Keyword: Aggression; Sexual Behavior
Link ID: 9782 - Posted: 06.24.2010

It’s long been known that experiencing control over a stressor immunizes a rat from developing a depression-like syndrome when it later encounters stressors that it can’t control. Now, scientists funded by the National Institute of Mental Health (NIMH), part of the National Institutes of Health (NIH), have unraveled the workings of the brain circuitry that inoculates against such hard knocks — the circuitry of resilience. Control not only activated the brain’s executive hub, the prefrontal cortex, but also altered it so that it later activated even when the stressor was not controllable. This activation turned off mood-regulating cells in the brainstem’s alarm center. The immunizing effect was so powerful that even a week later, when confronted with an uncontrollable stressor, the cells behaved as if the stressor was controllable and the rat was protected. “It’s as if the original experience with control leads the animal to later have the illusion of control even when it’s absent, thereby producing resilience in the face of challenge,” explained NIMH grantee Steven Maier, Ph.D., University of Colorado. “The prefrontal cortex is necessary for processing information about the controllability of stressors as well as applying this information to regulate responses to subsequent stressors.” A report on this first study exploring the neural mechanisms by which an initial experience with a controllable stressor can block the later behavioral effects of an uncontrollable stressor, by Maier, Jose Amat, Ph.D., and colleagues, appears in the December 20, 2006 issue of the Journal of Neuroscience.

Keyword: Stress
Link ID: 9781 - Posted: 06.24.2010

Michael Hopkin A US-led research team has developed a technique to filter potentially deadly prion proteins from blood. They suggest that the method should be used routinely in attempts to remove prions, which can cause variant Creutzfeldt-Jakob disease (vCJD), from blood products used for transfusions. The method could offer better protection than the current practice of removing white blood cells from donated blood, say the researchers, led by Robert Rohwer of the University of Maryland, Baltimore. Previous studies have shown that around a half of the abnormal, infective prion proteins are in white blood cells, so removing these can help reduce the risk of infection. But infective prions are also found in the blood plasma. Of the 200 vCJD cases recorded worldwide, only a few have involved contaminated blood transfusions, but health officials are still worried about this possible transmission route. Several countries have banned blood donations from people who have lived in Britain, where many people have potentially eaten meat containing infective prions. Despite the relatively few cases of this devastating, untreatable disease, researchers worry that many other people might be carriers. According to a survey of samples from tonsil and appendix removals, as many as 4,000 British people may be harbouring the disease, which can remain dormant for decades, without showing symptoms. There is currently no test to detect abnormal prions in humans, meaning that it is impossible to identify these people. ©2006 Nature Publishing Group

Keyword: Prions
Link ID: 9780 - Posted: 06.24.2010

EVANSTON, Ill. --- You know the sensation. When something has your full attention you see it vividly. And when you don't pay attention, you're liable to miss something important. Now a new Northwestern University study sheds light on how attention operates. The mystery of how attention improves the perception of incoming sensory stimulation has been a long-time concern of scientists. One hypothesis is that when you pay attention neurons produce stronger brain activity, as if the stimulus itself was stronger. That would mean that paying attention might make something appear more intense, and possibly distort its actual appearance. In the Northwestern study, EEG measures of brain activity were used to show precisely how attention alters brain activity. The team of psychologists and neuroscientists used a new strategy for understanding the mechanisms whereby sustained attention makes us process things more effectively, literally making the world come into sharper focus. "When you pay attention cells aren't only responding more strongly to stimuli," said co-author Marcia Grabowecky, research assistant professor of psychology in Northwestern's Weinberg College of Arts and Sciences. "Rather a population of cells is responding more coherently. It is almost like a conductor stepping in to control a large set of unruly musicians in an orchestra so that they all play together. Cells synchronize precisely to the conductor's cues."

Keyword: Attention
Link ID: 9779 - Posted: 12.21.2006

By REUTERS A chemical designed by doctors in Los Angeles could give earlier signals of Alzheimer’s disease and provide a new way to test treatments, a study has shown. Currently, the only way to diagnose the disease is to remove brain tissue or to perform an autopsy. The new study, to be published today in the New England Journal of Medicine, is by doctors at the University of California, Los Angeles, and is part of a larger quest to find a better method to diagnose the condition using tracers that can be detected with a positron emission tomography, or PET, scan. The new chemical, called FDDNP, attaches to abnormal clumps of proteins called amyloid plaques and nerve cell tangles that develop in Alzheimer’s sufferers and inhibit messages being processed by the brain. In the study, Dr. Gary Small and his colleagues discovered that the chemical allowed doctors to pick out which of 83 volunteers had Alzheimer’s, which had mild memory problems and which were functioning normally for their age. It was 98 percent accurate in determining the difference between Alzheimer’s and mild cognitive impairment, which surpassed the 87 percent success rate for a PET scan test that measured sugar metabolism in the brain, and the 62 percent accuracy rate when doctors used a magnetic resonance imaging. Copyright 2006 The New York Times Company

Keyword: Alzheimers
Link ID: 9778 - Posted: 06.24.2010

By ALEX BERENSON For at least a year, Eli Lilly provided information to doctors about the blood-sugar risks of its drug Zyprexa that did not match data that the company circulated internally when it first reviewed its clinical trial results, according to company documents. The original results showed that patients on Zyprexa, Lilly’s pill for schizophrenia, were 3.5 times as likely to experience high blood sugar levels as those taking a placebo, according to a February 2000 memo sent to top Lilly scientists. The memo is one of hundreds of internal Lilly documents provided to The New York Times by a lawyer in Alaska who represents mentally ill patients. But the results that Lilly eventually provided to doctors until at least late 2001 were very different. Those results indicated that patients taking Zyprexa were only slightly more likely to suffer high blood sugar as those taking a placebo, or an inactive pill. Another Lilly report, from November 1999, shows that Lilly found after examining 70 clinical trials that 16 percent of patients taking Zyprexa for a year gained more than 66 pounds. The company did not publicly disclose that figure, instead focusing on data from a smaller group of clinical trials that showed about 30 percent of patients gained 22 pounds. Copyright 2006 The New York Times Company

Keyword: Schizophrenia
Link ID: 9777 - Posted: 06.24.2010

By Will Dunham WASHINGTON (Reuters) - People with higher levels of vitamin D have a markedly reduced risk of developing multiple sclerosis (MS), according to a study published on Tuesday that may point to a promising way to protect against the disease. MS is an incurable and often disabling disease of the central nervous system that appears most often among young adults and affects 2 million people globally. Researchers at the Harvard School of Public Health in Boston combed a massive repository of serum samples from more than 7 million U.S. military personnel to find 257 people who developed MS. Their samples were analyzed for vitamin D levels and compared with a group of randomly picked military personnel from the same broad population who did not develop MS. Among the white people studied, the chances of developing MS fell as vitamin D levels in the body rose, according to findings published in the Journal of the American Medical Association. Among whites, the majority of those in the study, the risks of MS fell 62 percent for those in the top fifth of vitamin D concentration. © 1996-2006 Scientific American, Inc.

Keyword: Multiple Sclerosis
Link ID: 9776 - Posted: 06.24.2010

It is well known that animals use song as a way of attracting mates, but researchers have found that gibbons have developed an unusual way of scaring off predators – by singing to them. The primatologists at the University of St Andrews discovered that wild gibbons in Thailand have developed a unique song as a natural defence to predators. Literally singing for survival, the gibbons appear to use the song not just to warn their own group members but those in neighbouring areas. They said, "We are interested in gibbon songs because, apart from human speech, these vocalisations provide a remarkable case of acoustic sophistication and versatility in primate communication. Our study has demonstrated that gibbons not only use unique songs as a response to predators, but that fellow gibbons understand them." "This work is a really good indicator that non-human primates are able to use combinations of calls given in other contexts to relay new, and in this case, potentially life-saving information to one another. This type of referential communication is commonplace in human language, but has yet to be widely demonstrated in some of our closest living relatives - the apes." Gibbons are renowned amongst non-human primates for their loud and impressive songs that transmit over long distances and are commonly used in their daily routine when mating pairs 'duet' every morning. Songs in response to predators – mostly large cats, snakes and birds of prey – have been previously noted, but no extensive research into its purpose or understanding by other gibbons has been done until now.

Keyword: Language
Link ID: 9775 - Posted: 06.24.2010

"'Tis Better to Give Than Receive" The phrase typically attributed to a verse in the Christian New Testament is now proving to be hard-wired into our brains. Brain scanning research is revealing that generosity seems to be a built in human trait. "You give from the heart and… it satisfies your brain," says Jordan Grafman, chief of the Cognitive Neuroscience Section the National Institute of Neurological Disorders and Stroke (NINDS), a division of the National Institutes of Health (NIH). Grafman and his team study aspects of the human brain that set us apart from other species, with the aim of using that knowledge to better test when things go wrong in our brains, and whether new treatments are effective. They decided to study which areas of the human brain are involved in donating to organizations "because we know that that's something that other species just don't do," he says. They used a technique called functional MRI. It reveals which brain structures are most active relative to the rest of the brain when people perform certain mental tasks. They asked 19 healthy volunteers to play a computer game while having their brains scanned. In addition to dispensing cash rewards, the game also asked for donations to charities. "When they donated, either they could donate and it wouldn't cost them personally or they could donate and it might cost them some money," explains Grafman. © ScienCentral, 2000-2006.

Keyword: Emotions
Link ID: 9774 - Posted: 06.24.2010

Kerri Smith A nativity story with a twist is playing out this Christmas in two zoos in the UK. At Chester Zoo, a Komodo dragon named Flora awaits the birth of eight babies, and another four dragons have already hatched at London Zoo — each and every one the product of a virgin conception. The miraculous births, which are all males, could be a product of keeping this threatened species in captivity, say researchers, and could have implications for the continued health of zoo-bound populations. Parthenogenesis — reproduction without the need for fertilization by a male — is rare in vertebrates. Some animals, including several lizard species, are known to be capable of it. But Komodo dragons have never been seen to breed like this before. Yet in the space of 8 months, two of the three Komodo dragons in the UK have reproduced parthenogenetically. Zoo keepers knew something strange was happening because the female dragons had not been around any males within the period during which they must have become pregnant. To confirm the dragons' parentage, a team led by Phillip Watts at the University of Liverpool used genetic fingerprinting. Their results, published in Nature this week1, show that the dragon sons are not direct clones of their mothers, but that the babies' DNA contains half as much variation as is present in the mother's genes, indicating that it represents a doubling up of one set of mother's chromosomes. The results show that no other Komodo dragon could have been involved in their conception. ©2006 Nature Publishing Group

Keyword: Sexual Behavior
Link ID: 9773 - Posted: 06.24.2010

Helen Pearson The obese are often blamed for their own corpulence. But perhaps, just perhaps, some of the blame should be placed on another type of organism entirely: bacteria. Researchers have shown that the intestines of obese people are swimming with a different make-up of microbes compared with those of slim people. And this microbial population could actually be helping them gain weight: bugs taken from an obese mouse and transplanted into another animal's intestine made the animals gain more fat than normal. The researchers propose that the obese-prone microbes glean more calories from food, which are sucked up by the body and deposited as excess fat. "Minor differences in the calories you can harvest might play an important role in predisposition to obesity," says Jeffrey Gordon at the Washington University School of Medicine in St Louis, who led the studies. The implications for people trying to lose weight are, for now, unclear. It isn't known how easy it is to change a person's microbial balance, for example, or whether that might have unwanted health consequences. On top of all that, notes obesity expert Stephen Bloom of Imperial College London, the body's other weight-regulating mechanisms might step in to compensate for any gut microbe changes. Every person's gut is home to a unique cocktail of trillions of bacteria and other minute bugs that help to break down food and fight off invading pathogens. In 2004, Gordon first proposed that this medley of microbes might help control body weight. ©2006 Nature Publishing Group

Keyword: Obesity; Neuroimmunology
Link ID: 9772 - Posted: 06.24.2010