By Charles Q. Choi Chimpanzees readily learn and share techniques on how to fiddle with gadgets, new research shows, the best evidence yet that our closest living relatives pass on customs and culture just as humans do. The new findings help shed light on the capabilities of last common ancestor of humans and chimps. And the research could also help develop better robots and artificial intelligences, the researchers say In the wild, chimpanzee troops often are distinct from one another, possessing collections of up to 20 traditions or customary behaviors that altogether seem to form unique cultures. Such practices include various forms of tool use, including hammers and pestles; courtship rituals such as leaf-clipping, where leaves are clipped noisily with the teeth; social behaviors such as overhead hand-clasping during mutual grooming; and methods for eradicating parasites by either stabbing or squashing them. While observing chimpanzees, evolutionary psychologist Antoine Spiteri at the University of St. Andrews in Scotland wanted to help settle the question of whether or not the apes learned such practices by watching others like humans do, as opposed to simply knowing how to perform such behaviors innately. © 2007 MSNBC.com © 2007 Microsoft

Keyword: Evolution
Link ID: 10385 - Posted: 06.24.2010

By NICHOLAS WADE Applying a new genomic technique to a large group of patients, researchers in Britain have detected DNA variations that underlie seven common diseases, discovering unexpected links between them. The variations pinpoint biological pathways underlying each of the diseases, and researchers hope that as the pathways are analyzed, new drugs and treatments will emerge. The seven common diseases are bipolar disorder, coronary artery disease, Crohn’s disease, hypertension, rheumatoid arthritis, and Type 1 and Type 2 diabetes. Unveiling the complex genetics of common diseases was the promised payoff of the $3 billion human genome project, completed in 2003, but progress was slow until the recent development of devices that in a single operation can read the DNA sequence at up to 500,000 points across an individual’s genome. With the devices, called chips, researchers can compare large numbers of patients with healthy individuals, looking for points of differences in their genomes that may be associated with disease. The approach is known as whole genome association, and studies on Type 2 diabetes, heart disease and breast cancer have been reported within the last few weeks. Those and the new study, which was financed by the Wellcome Trust of London, demonstrate the power and reliability of the whole genome association method, which stands in contrast to the many uncorroborated claims of disease genes made previously. Copyright 2007 The New York Times Company

Keyword: Schizophrenia; Genes & Behavior
Link ID: 10384 - Posted: 06.24.2010

In a laboratory at the University of Texas Southwestern Medical Center in Dallas, researchers study a mouse swimming in a pool of milky water. While it looks like any other mouse, something is quite different about this mouse's genetically-modified brain. It finds a hidden platform in the water much faster than the other mice. This smart mouse is giving brain researchers new insights into intelligence. "Most people think of intelligence, they think learning and remembering," brain researcher James Bibb says. "However, flexibility in the face of changing situations may be a more important feat of intelligence." By turning off a certain gene, James Bibb (left) and his team found that the mice became smarter. James Bibb and his team didn't set out to make mice smarter. They simply wanted to study the function of a gene nobody knew much about. "We wanted to understand features of the brain's function and we didn't expect the animals to end up showing improved or enhanced performance in anything," he says. "We expected deficiencies to appear and for that to tell us what the role of this gene for Cdk5 was." Bibb wanted to study the Cdk5 gene because it is suspected to be involved in Alzheimer's disease as well as in drug addictions. © ScienCentral, 2000-2007

Keyword: Learning & Memory; Genes & Behavior
Link ID: 10383 - Posted: 06.24.2010

NEW YORK (Reuters Health) - A pre-existing defect in body temperature regulation may be a factor underlying some fatal reactions to the illegal "club drug" ecstasy (3,4-methylenedioxymethamphetamine, MDMA), researchers from Canada propose. "Fatal MDMA intoxication is idiosyncratic and the reasons why some ecstasy users are especially susceptible to the toxic effects of the drug are still unknown," Dr. Stephen J. Kish of the University of Toronto and the Centre for Addiction and Mental Health and colleagues point out. They also note that deaths attributed to MDMA intoxication, which are fairly infrequent compared with the estimated number of recreational users, are often associated with a sharp increase of body temperature, also referred to as hyperthermia. In the current issue of the Journal of Forensic Sciences, Kish's team describes a 24-year-old woman who developed fatal hyperthermia with complications affecting multiple organs after taking ecstasy. An autopsy showed that the woman had diffuse thyroid hyperplasia (also called Graves' disease), a thyroid disorder that could have made her less tolerant to heat. Comprehensive drug screening showed only MDMA and traces of methamphetamine in a blood sample collected 3 to 4 hours after the woman took the drugs. © 1996-2007 Scientific American, Inc.

Keyword: Drug Abuse; Hormones & Behavior
Link ID: 10382 - Posted: 06.24.2010

By Lucas Laursen Heavy snacking after exercise may have little to do with hunger or appetite hormones. In a new study, people who rode a bike for an hour ate more for lunch than those who just sat around ate, despite similar levels of hunger and short-term appetite-suppressing hormones. The urge to gobble after exercise, it turns out, may be a more complicated mixture of psychology and body chemistry. Hoping to get a better sense of why many people chow down after an hour at the gym, graduate student Cátia Martins of the University of Surrey, U.K., and colleagues recruited 12 adult volunteers with normal weight and eating habits, half of them male and half female. The team then divided the volunteers into two groups. Both groups drank a cup of hot chocolate for breakfast, but 1 hour later, volunteers from one group took a moderate 60-minute spin on a stationary bike, while volunteers in the other group sat around reading or writing. At the end of either activity, the researchers provided both groups with identical buffet lunches of unlimited sandwiches, fruit, cake, cookies, and yogurt. At various points throughout the experiment, Martins and her colleagues collected blood samples from the subjects and had them fill out a questionnaire about their hunger. During their workout, the exercisers reported less hunger than the inactive volunteers and had elevated levels of PYY, GLP-1, and PP, hormones that suppress appetite in the short term. By lunchtime, both groups reported similar amounts of hunger, and both had indistinguishable levels of the three hormones. Yet the exercisers out-ate the slackers, consuming nearly 20% more calories at lunch. © 2007 American Association for the Advancement of Science.

Keyword: Obesity
Link ID: 10381 - Posted: 06.24.2010

Jennifer Viegas, Discovery News — Neanderthals likely did not possess the cognitive complexities of modern humans and, as a result, probably did not suffer from schizophrenia and certain other mental disorders, according to a new theory. The theory proposes that language, creativity and many mental diseases are linked, due to the fact that they may originate in the neocortex, as well as the densely cell-packed cortex, located towards the top of the brain. These brain regions appear to mature and develop more slowly than other areas. Although there are conflicting claims about possible Neanderthal creative abilities, no direct evidence supports that this extinct human species or subspecies possessed full-fledged grammatical language. Neanderthals had large brains, but researchers believe their mental skills matured rapidly, closing the door to disorders associated with the cortex. Modern humans, on the other hand, must take the bad with the good. "In a nutshell, I feel that the extremely long maturation time of our brains — greater than 20 years — allows them to develop many and various capabilities, such as language and schizophrenia," H. Lee Seldon, the theory’s author, told Discovery News. © 2007 Discovery Communications Inc.

Keyword: Evolution
Link ID: 10380 - Posted: 06.24.2010

Researchers have identified a master hormone that allows the body to fuel itself with stored fat during times of fasting. The hormone mobilizes lipids from fat cells, and then directs the liver to transform those lipids into energy-rich molecules that circulate throughout the body. The researchers said their findings reveal a more complete picture of the far-reaching role of the hormone, fibroblast growth factor 21 (FGF21), which is already in development as a treatment for type 2 diabetes. In addition to switching the body to a fat-burning mode, the team found FGF21 induces the hibernation-like state of torpor that conserves energy in fasting animals. FGF21's unexpectedly broad role in fat-burning was reported in two papers published in the June, 2007, issue of the journal Cell Metabolism. One paper was from the laboratory of Steven Kliewer and Howard Hughes Medical Institute investigator David Mangelsdorf at the University of Texas Southwestern Medical Center. Coauthors on the paper are Kliewer and Mangelsdorf's colleagues at UT Southwestern and scientists from Van Andel Research Institute and New York University School of Medicine. The other Cell Metabolism paper was by Eleftheria Maratos-Flier of Harvard University and colleagues. © 2007 Howard Hughes Medical Institute

Keyword: Obesity
Link ID: 10379 - Posted: 06.24.2010

A segment of animated footage promoting the 2012 Olympics has been removed from the organisers' website after fears it could trigger epileptic seizures. Prof Graham Harding, who developed the test used to measure photo-sensitivity levels in TV material, said it should not be broadcast again. Charity Epilepsy Action said it had received calls from people who had suffered fits after seeing it. Organiser London 2012 said it will re-edit the film. The new logo for the event, which is a jagged emblem based on the date 2012, was unveiled on Monday. A London 2012 spokeswoman said the health concerns surrounded a piece of animation shown at the launch, which was recorded by broadcasters and put on the official website. Emphasising that it was not the logo itself which was the focus of worries, she said: "This concerns a short piece of animation which we used as part of the logo launch event and not the actual logo." She said the section of footage concerned showed a "diver diving into a pool which had a multi-colour ripple effect". The spokeswoman said: "We are taking it very seriously and are looking into it as a matter of urgency." Prof Harding is an expert in clinical neuro-physiology and he designed a test which all moving adverts need to undergo to check they will not trigger a reaction in people with epilepsy. He told BBC London 94.9FM: "It fails the Harding FPA machine test which is the machine the television industry uses to test images. And so it does not comply with Ofcom guidelines and is in contravention of them. The brand incorporates both the Olympic and Paralympic Games, which is ironic as the latter is a showcase for athletes with disabilities (C)BBC

Keyword: Epilepsy; Vision
Link ID: 10378 - Posted: 06.09.2007

Roxanne Khamsi Mice that lack the gene for an important brain-signalling chemical are 10 times less physically active and carry twice as much body fat as their control counterparts, a study reveals. The researchers speculate that mutations in this gene - known as brain specific homeobox transcription factor (Bsx) - could explain why some people fidget less than others and as a result put on more weight, even on a healthy diet. Mathias Treier at the European Molecular Biology Laboratory in Heidelberg, Germany, and colleagues engineered a set of mice to lack the Bsx gene and tagged the animals with transponders. Over the course of the experiment the team monitored the animals' weight and movements within the cages. By the time these mice reached three months of age they had about 3 grams of body fat - roughly twice the amount of their control counterparts, even though both groups ate the same healthy diet. According to Treier, this difference persisted in subsequent months as the mice matured. Treier noticed something that could explain this disparity: the mice lacking Bsx engaged in far less spontaneous activity and sat in place for long stretches of time - much like a human "couch potato". The normal mice, by comparison, fidgeted frequently, regularly wandering about the cage. © Copyright Reed Business Information Ltd.

Keyword: Obesity; Genes & Behavior
Link ID: 10377 - Posted: 06.24.2010

UK scientists are attempting to restore vision in people with a leading cause of blindness using stem cells. The team have already repaired the vision of a handful of patients with age-related macular degeneration using cells from the patients' own eyes. With the help of a £4m donation, they are now planning to carry out the same operation using retinal cells grown from stem cells in the lab. It is hoped the first patients would be treated within five years. Age-related macular degeneration (AMD) affects around 25% of over-60s in the UK to some degree and causes blindness in 14 million people across Europe. There are two types - dry - which makes up 90% of cases, and wet, which makes up the other 10%. It is caused by the failure of retinal pigment epithelial cells (RPE) - a layer of cells under the retina. Using stem cells - which are far more adaptable - can only improve success of what has already been achieved and in addition establish this as a global therapy Mr Lyndon Da Cruz, consultant ophthalmic surgeon at Moorfields Eye Hospital in London has carried out an operation in a handful of patients to take cells from the periphery of the eye in patients with wet AMD and transplant them into the affected area. The procedures have been successful but are associated with complications, take more than two hours and require two operations. To make the procedure quicker, easier and more widely available, researchers at the University of Sheffield have grown RPE cells from embryonic stem cell lines. The hope is that this can be processed into a layer that can be injected into the patients' eye during a simple 45-minute operation. Tests of the laboratory grown RPE cells in rats with AMD showed they restored blindness. (C)BBC

Keyword: Vision; Stem Cells
Link ID: 10376 - Posted: 06.05.2007

Agricultural workers exposed to high levels of pesticides have a raised risk of brain tumours, research suggests. The French study also indicated a possible higher risk among people who used pesticides on houseplants. All agricultural workers exposed to pesticides had a slightly elevated brain tumour risk, it suggested. But the Occupational and Environmental Medicine study found the risk was more than doubled for those exposed to the highest levels. The risk of a type of central nervous system tumour known as a glioma was particularly heightened among this group - more than three times the risk in the general population. Gliomas are more common in men than women, and the researchers speculate that part of the reason might be that men are more often exposed to pesticides. However, the overall risk of developing a brain tumour remained very low. UK experts said the findings were inconclusive. The findings were based on an analysis of 221 cases of brain tumours by the French Institute of Public Health, Epidemiology and Development. The research took place in the Bordeaux wine-growing region, where 80% of all pesticides used are fungicides. The chemicals are mixed and sprayed in a mist to protect vines from fungal attack. However, the researchers were unable to get specific enough data to pin down exactly which types of pesticide were associated with the development of brain tumours. (C)BBC

Keyword: Neurotoxins; Parkinsons
Link ID: 10375 - Posted: 06.05.2007

By BENEDICT CAREY DENVER — Almost every parent of young children has heard an anguished cry or two (or 200) something like: “This shirt is scratchy, this shirt is scratchy, get it off!” “This oatmeal smells like poison, it’s poisonous!” “My feet are hot, my feet are hot, my feet are boiling!” Such bizarre, seemingly overblown reactions to everyday sensations can end in tears, parents know, or escalate into the sort of tantrum that brings neighbors to the door asking whether everything’s all right. Usually, it is. The world for young children is still raw, an acid bath of strange sights, smells and sounds, and it can take time to get used to it. Yet for decades some therapists have argued that there are youngsters who do not adjust at all, or at least not normally. They remain oversensitive, continually recoiling from the world, or undersensitive, banging into things, duck-walking through the day as if not entirely aware of their surroundings. Copyright 2007 The New York Times Company

Keyword: Pain & Touch; Hearing
Link ID: 10374 - Posted: 06.24.2010

Every day humans make thousands of decisions, small and large, based on the information at hand and their assessment of the potential outcome of those choices. Now, in a pioneering study of rhesus macaque monkeys, a team of researchers from the Howard Hughes Medical Institute (HHMI) at the University of Washington has caught primates in the act of probabilistic reasoning. They have measured the electrical activity at play in brain cells as the animals make a choice based on their interpretation of a set of visual cues and the potential for reward. Writing June 3, 2007 in an advance online publication of the journal Nature, a team of researchers led by HHMI investigator Michael N. Shadlen at the University of Washington describes experiments in which monkeys learned to base their decisions on the combined probabilities for reward of a random sequence of shapes presented on a video screen. In the process, Shadlen and colleague Tianming Yang, also of the University of Washington, measured the response of neurons in a region of the brain associated with vision, motor planning and attention. “It's amazing the monkeys can do this,” said Shadlen, “and it's pretty incredible you can find neurons in the brain that are doing these calculations.” © 2007 Howard Hughes Medical Institute.

Keyword: Attention
Link ID: 10373 - Posted: 06.24.2010

By Kathi Mestayer The hardest thing I've had to come to terms with in the 17 years since my hearing started to fail is not silence but intrusive noises: They ring in my ears, obscure the sounds I want to listen to and startle me when they amplify themselves without warning. There I am, working quietly at my desk, when the knock at my door becomes -- Crash! -- a tympanic interruption, and I leap to attention. Mine is what's called sensorineural hearing loss, which can be caused by loud noises and is often associated with aging (I was 35 when it began) but in my case is probably genetic. Most of my immediate family members have lost their hearing as they've aged, and they walk around, like me, with hunks of beige-ish plastic in and around their ears. Fifteen percent of American adults have some kind of hearing loss, according to the National Institute on Deafness and Other Communication Disorders. Those of us in that group have learned to adapt to a world that ever larger numbers of people are likely to share because more of us are getting, well, older. You have to wonder whether kids these days are ruining their hearing with all that loud music piped from iPods directly into their ear canals. There's no doubt that noise causes hearing loss, but there is no hard evidence yet that noise-induced hearing loss is on the rise. In any event, I'm hardly in a position to give that lecture, having danced through my share of rock concerts, right in front of amps that were bigger than I was. © 2007 The Washington Post Company

Keyword: Hearing
Link ID: 10372 - Posted: 06.24.2010

Michael Reilly A note to the forgetful: be thankful you don’t remember everything. It means your brain is working properly. According to a new study, the brain only chooses to remember memories it thinks are most relevant, and actively suppresses those that are similar but less used, helping to lessen the cognitive load and prevent confusion. Brice Kuhl at Stanford University in California, US, and colleagues used functional magnetic resonance imaging (fMRI) to measure the brain activity of 20 healthy adults while they performed a simple memory test. Participants were given three words pairs to memorise, including two pairs that were closely associated, as follows: ATTIC dust ATTIC junk MOVIE reel After studying "ATTIC dust" a second time, subjects were asked to recall all three pairs using the first words as cues. On average, people were 15% worse at recalling "ATTIC junk" than they were at recalling the unrelated pair, "MOVIE reel". Comparing these findings to the fMRI data taken during the test, the team found participants’ brains were highly active in a region known for handling competing memories, and also in an area believed to induce memory suppression. © Copyright Reed Business Information Ltd.

Keyword: Learning & Memory
Link ID: 10371 - Posted: 06.24.2010

Katharine Sanderson Pairs of Australian magpie-larks (Grallina cyanoleuca) that sing in tune and in tempo are more threatening to rivals whose territory they move in on than pairs that can't quite get their twittering coordinated. Michelle Hall from the Max Planck Institute for Ornithology, working at the Australian National University in Canberra with Robert Magrath, listened closely to the shared songs of breeding pairs of the birds. The most coordinated magpie-lark pairs sang alternating notes of the song in a way that, to an untrained ear, gave the impression of being a single voice. Uncoordinated pairs don't get the alternation quite right and produce overlapping notes. Hall then played recordings of coordinated and uncoordinated songs within the territory of 12 magpie-lark pairs. The most closely coordinated songs provoked the most aggressive territorial defence response from the male birds being 'invaded'. These birds who thought their territory was under threat responded by singing more in return. The research raises a number of questions, not least what is so intimidating about a coordinated song, says Peter Slater, an expert in bird duetting at the University of St Andrews, Scotland. "They're producing a song that might as well be produced by an individual," says Slater. "High coordination might be an indication that these are rivals not to be messed with," he suggests. ©2007 Nature Publishing Group

Keyword: Sexual Behavior; Animal Communication
Link ID: 10370 - Posted: 06.24.2010

Scientists have shown how having a stroke - or even snoring heavily - can increase the risk of developing Alzheimer's disease. A Leeds team found a lack of oxygen in the brain, which occurs during strokes or even in heavy snorers, can affect brain cells called astrocytes. The changes to the cells let glutamate, a neurotransmitter, build up - which could contribute to Alzheimer's. The Journal of Neuroscience study may help scientists prevent Alzheimer's. Under normal circumstances astrocytes mop up glutamate in the brain. However, the Leeds team found a lack of oxygen decreased the expression of proteins required by the cells to carry out this task. Glutamate is toxic if allowed to build up in high levels, so the accumulation could lead to brain cell death, and eventually to the onset of Alzheimer's. Lead researcher Professor Chris Peers said the study was important as it suggested why beta amyloid, the protein that builds up in the brains of Alzheimer's patients, is key to the process of triggering disease. It is already known that low oxygen can cause astrocytes to increase their production of beta amyloid. The latest research suggests it may be this increased production of beta amyloid that blocks expression of the proteins needed for astrocytes to mop up excess glutamate. Professor Peers said: "This is an important factor in what's going on in hypoxic brains. Even though the patient may outwardly recover, the hidden cell damage may be irreversible." (C)BBC

Keyword: Alzheimers; Stroke
Link ID: 10369 - Posted: 06.04.2007

Susan Endersbe, a schizophrenic who lived in Minneapolis, battled depression all her life. When her illness worsened, she usually checked into a hospital, which she did for the last time on May 7, 1994. On that occasion, doctors gave her an antidepressant, and three weeks later she said she felt ready to leave soon, according to nurses’ notes. The next day, she was referred to Dr. Faruk Abuzzahab and agreed to participate in a drug study he was being paid to conduct, although her suicidal tendencies should have excluded her. Dr. Abuzzahab stopped giving her the antidepressant, and she was forced to wait nearly two weeks before receiving either an experimental drug or a placebo. Throughout those weeks, Dr. Abuzzahab recorded Ms. Endersbe’s adverse effects as “0,” but nurses documented a steady decline. Ms. Endersbe expressed reservations about being part of a study. “I guess I didn’t understand that I would be going off all my other medications,” she told a hospital worker, according to records. She spoke repeatedly of killing herself, even telling a nurse in a late-night talk on June 8 that she planned to jump off the Franklin Avenue Bridge, “but says she is safe in the hospital,” a hospital worker wrote. On June 10, Dr. Abuzzahab wrote in her chart that Ms. Endersbe was “medically improving.” He gave her permission to visit her apartment alone, although leaving the hospital violated the study’s rules and she had spoken of suicide only the night before. Copyright 2007 The New York Times Company

Keyword: Schizophrenia; Depression
Link ID: 10368 - Posted: 06.24.2010

By Susan DeFord Randy and Lynn Gaston received the distressing diagnosis not once but three times. Their sons, Zachary, Hunter and Nicholas, are triplets, and as the brown-haired boys grew into toddlers, Lynn noticed how oddly they played, how little they babbled, how they cried inconsolably at doctor's offices and family gatherings. Two years ago, when the boys were 4, specialists confirmed the Gastons' suspicions: The boys have varying degrees of autism, a neurological disorder that hampers communication and social interactions and can include obsessive-compulsive behavior. "It was shocking," Lynn said, "but in my heart, I knew, yes, somebody finally sees it." The diagnosis launched a transformation of the Gastons' lives. Now even mundane details of the daily routine are carefully orchestrated, driven by the boys' need for sameness: identical sheets on their beds, baths in the same order every night, the same kind of pizza from the same kind of box. The Gastons rarely go out as a couple; it's difficult to find babysitters. The family has never eaten in a restaurant together, because crowded, unfamiliar environments sometimes make the boys anxious and upset. And the couple never get a full night's rest. Like many autistic children, the boys don't sleep well, going to bed at 8 p.m. and often waking for the day between 2 a.m. and 3 a.m. © 2007 The Washington Post Company

Keyword: Autism
Link ID: 10367 - Posted: 06.24.2010

Alison Abbott You've walked your normal route home a thousand times. Twice, a lurking gang of teenagers jeered as you went by. Most people would see the threat of attack on any day for what it is — minimal. But a few would be too scared to risk the journey alone ever again. Such over-anxious people tend to interpret a potentially dangerous situation as intolerably threatening, even when the risk is tiny. Researchers have now uncovered the neural circuits behind this inappropriate behaviour — at least in mice. Humans probably have a similar system, say the researchers who made the discovery. Knowing the actual cells involved in one manifestation of anxiety might help those developing new therapies. If normal mice are given an electric shock every time they are exposed to a flash of light, they will quickly learn to freeze with fear every time the light flashes. If they get the shock only occasionally, they will show less fear after the cue. But mice lacking a particular receptor for the neurotransmitter serotonin, called 5-Htr1a, show the same level of fear in both cases. Such mice are anxious, and cannot evaluate the true threat of an ambiguous situation. ©2007 Nature Publishing Group

Keyword: Emotions; Genes & Behavior
Link ID: 10366 - Posted: 06.24.2010