By Steve Mitchell Peer pressure may push teens to start smoking, but their DNA keeps them hooked on the nicotine buzz into their adult years. So says a new study that finds that people with variations in particular genes are more likely to become addicted if they start smoking during early adolescence. The work may explain why some people find it harder to kick the habit and also underscores the importance of preventing children from smoking in the first place. Previous research has shown that people who start smoking during adolescence are more likely to be heavy smokers as adults; they also find it harder to quit than those who first begin lighting up later in life. Certain genes may influence whether people get hooked on cigarettes during their teen years, but nobody had pinpointed which ones. Three recent studies found that people with a single nucleotide base change in the genes that code for cell receptors that bind nicotine--the addictive chemical in cigarettes--were more likely to develop lung cancer (ScienceNOW, 2 April). Because the genes help produce nicotine's buzz, a team led by Robert Weiss, a geneticist at the University of Utah in Salt Lake City, wanted to determine if variations in their sequences influence whether people develop a stronger addiction to cigarettes. © 2008 American Association for the Advancement of Science.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 11808 - Posted: 06.24.2010

Catherine Brahic "Robo-frog" has a way with the ladies. He has a speaker that broadcasts a realistic mating call and a shiny painted balloon that inflates and vibrates beneath his throat, perfectly mimicking the vocal sac of a real túngara frog. Researchers at the University of Texas are using robo-frog to study different components of communication between the frogs. And the Texas team has found good evidence that the striped vocal sac is important for wooing females, even though they mate in the dark. Túngara frogs live in the forests of northern Latin America. At night, males sing to attract females and their throats inflate. "The sacs evolved for males to shuttle air back and forth, so they don't have to suck in air each time they sing," says Michael Ryan of the University of Texas in Austin. Since the female frogs can see very well in the dark, Ryan and his colleague Ryan Taylor thought the distinctive pattern on the males' vocal sac might have another purpose as well. In experiments, females will move towards a speaker playing a recorded male mating call. But to test whether the vocal sac also played a role, the researchers created robo-frog – a resin replica of a male túngara frog with an inflatable latex vocal sac. © Copyright Reed Business Information Ltd.

Keyword: Sexual Behavior; Animal Communication
Link ID: 11807 - Posted: 06.24.2010

Many of the seemingly disparate mutations (http://www.nimh.nih.gov/science-news/2007/tiny-spontaneous-gene-mutations-may-boost-autism-risk.shtml) recently discovered in autism (http://www.nimh.nih.gov/health/topics/autism-spectrum-disorders-pervasive-developmental-disorders/index.shtml) may share common underlying mechanisms, say researchers supported in part by the National Institute of Mental Health (NIMH), a part of the National Institutes of Health (NIH). The mutations may disrupt specific genes that are vital to the developing brain, and which are turned on and off by experience-triggered neuronal activity. A research team led by Christopher Walsh, M.D., Ph.D., and Eric Morrow, M.D., Ph.D., of Harvard University, found two large sections missing on chromosomes in people with autism and traced them to likely inherited mutations in such genes regulated by neuronal activity. They report their findings in the July 11, 2008 issue of Science. The study breaks new ground for complex disorders like autism, taking advantage of a shortcut to genetic discovery by sampling families in which parents are cousins. The researchers found genes and mutations associated with autism in 88 families from the Middle East, Turkey and Pakistan in which cousins married and had children with the disorder. “The emerging picture of the genetics of autism is quite surprising. There appear to be many separate mutations involved, with each family having a different genetic cause,” explained NIMH Director Thomas R. Insel, M.D. “The one unifying observation from this new report is that all of the relevant mutations could disrupt the formation of vital neural connections during a critical period when experience is shaping the developing brain.”

Keyword: Autism; Genes & Behavior
Link ID: 11806 - Posted: 06.24.2010

By Alexis Madrigal Some birds, caged or not, only sing when they really need to, namely, during the breeding season. After it's over, their musical neurons die-off, and they are left tune-less. But now, scientists at the University of Washington have shown they can keep the birds singing, temporarily, by stopping the action of an enzyme key to their brains' natural cell-death processes. As cell-death mechanisms are similar across species, the research could open up new avenues of research on degenerative and age-related diseases like Alzheimer's. Programmed cell death, or apoptosis, is common in multicellular organisms and aids important biological processes, like maintaining homeostasis and acting as the chisel in skeletal development. While there are many reasons that a cell could sense it is supposed to die, the actual suicide process is generally the same: A group of enzymes called caspases execute on the order for cellular degeneration. What the researchers have shown in work to be published tomorrow in the Journal of Neuroscience is that inhibiting the caspases preserves neurons and brain-region function; in this case, singing. "In the future, physicians might be able to stabilize people who have suffered a stroke using these inhibitors," said Eliot Brenowitz, a University of Washington professor of psychology and zoology, in a release. © 2008 CondéNet, Inc.

Keyword: Sexual Behavior; Apoptosis
Link ID: 11805 - Posted: 06.24.2010

Researchers in the U.S. have identified the emergence of a new type of brain-wasting disease that resembles Creutzfeld-Jakob, the human form of mad cow disease. Similarly to Creutzfeld-Jakob disease (CJD), the human variant of bovine spongiform encephalopathy, the new disease causes the brains of sufferers to fill with tiny holes, robbing them of the ability to think, speak and move. In the U.S., it has been found in 16 people since 2002, 10 of whom have died of it. Cases of the disease were first described in the Annals of Neurology in 2006 and are discussed in an article in the June 20 issue of the journal and in a July 9 article in New Scientist. "I believe the disease has been around for many years, unnoticed," Pierluigi Gambetti, director of the U.S. National Prion Disease Pathology Surveillance Center at Case Western Reserve University in Cleveland, Ohio, said in a news release Wednesday. It's believed that excessive amounts of prions, misfolded forms of a brain protein, lead to breakdown of brain tissue in both types of brain-wasting diseases. In the case of CJD, prions are not broken down by enzymes, but in the new disease, they are. © CBC 2008

Keyword: Prions
Link ID: 11804 - Posted: 06.24.2010

By CARLA K. JOHNSON CHICAGO -- Pressured by desperate parents, government researchers are pushing to test an unproven treatment on autistic children, a move some scientists see as an unethical experiment in voodoo medicine. The treatment removes heavy metals from the body and is based on the fringe theory that mercury in vaccines triggers autism _ a theory never proved and rejected by mainstream science. Mercury hasn't been in childhood vaccines since 2001, except for certain flu shots. But many parents of autistic children are believers, and the head of the National Institute of Mental Health supports testing it on children provided the tests are safe. "So many moms have said, `It's saved my kids,'" institute director Dr. Thomas Insel said. For now, the proposed study, not widely known outside the community of autism research and advocacy groups, has been put on hold because of safety concerns, Insel told The Associated Press. The process, called chelation, is used to treat lead poisoning. Studies of adults have shown it to be ineffective unless there are high levels of metals in the blood. Any study in children would have to exclude those with high levels of lead or mercury, which would require treatment and preclude using a placebo. © 2008 The Associated Press

Keyword: Autism
Link ID: 11802 - Posted: 06.24.2010

By Clara Moskowitz Some songbirds can contract their vocal muscles with the fastest muscle movements yet described — about 100 times faster than humans can blink an eye, according to new research. The study found that two types of songbirds produce their tunes with superfast muscles, similar to those used by rattlesnakes, several fish and the ringdove (a type of pigeon). "We discovered that the European starling (found throughout Eurasia and North America) and the zebra finch (found in Australia and Indonesia) control their songs with the fastest-contracting muscle type yet described," said Coen Elemans, who conducted the study as a postdoctoral researcher in biology at the University of Utah. © 2008 LiveScience.com.

Keyword: Animal Communication; Muscles
Link ID: 11801 - Posted: 06.24.2010

By John Horgan I'm 54, with all that entails. Gray hair, trick knee, trickier memory. I still play a mean game of hockey, and my love life requires no pharmaceutical enhancement. But entropy looms ever larger. Suffice it to say, I would love to believe that we are rapidly approaching “the singularity.” Like paradise, technological singularity comes in many versions, but most involve bionic brain boosting. At first, we'll become cyborgs, as stupendously powerful brain chips soup up our perception, memory, and intelligence and maybe even eliminate the need for annoying TV remotes. Eventually, we will abandon our flesh-and-blood selves entirely and upload our digitized psyches into computers. We will then dwell happily forever in cyberspace where, to paraphrase Woody Allen, we'll never need to look for a parking space. Sounds good to me! Notably, singularity enthusiasts tend to be computer specialists, such as the author and retired computer scientist Vernor Vinge, the roboticist Hans Moravec, and the entrepreneur Ray Kurzweil. Intoxicated by the explosive progress of information technologies captured by Moore's Law, such singularitarians foresee a “merger of biological and nonbiological intelligence,” as Kurzweil puts it, that will culminate in “immortal software-based humans.” It will happen not within a millennium, or a century, but no later than 2030, according to Vinge. These guys—and, yes, they're all men—are serious. Kurzweil says he has adopted an antiaging regimen so that he'll “live long enough to live forever.”

Keyword: Miscellaneous
Link ID: 11800 - Posted: 06.24.2010

Colin Barras Nine years ago, a brain-stem stroke left Erik Ramsey almost totally paralysed, but with his mental faculties otherwise intact. Today he is learning to talk again – although so far he can only manage basic vowel sounds. In 2004, Ramsey had an electrode implanted in his speech-motor cortex by Philip Kennedy's team at Neural Signals, a company based in Duluth, Georgia, US, who hoped the signal from Ramsey's cortex could be used to restore his speech. Interpreting these signals proved tricky, however. Fortunately, another team headed by Frank Guenther at Boston University, Massachusetts, US, has been working on the same problem from the opposite direction. Guenther and his colleagues have used information from brain scans of healthy patients to monitor neural activity during speech. These studies show that the brain signals don't code for words, but instead control the position of the lips, tongue, jaw and larynx to produce basic sounds. Guenther's research group then developed software that could recognise and translate the patterns of brain activity during speech. © Copyright Reed Business Information Ltd.

Keyword: Stroke; Language
Link ID: 11799 - Posted: 06.24.2010

By Virginia Morell To a female frog, the mating season must sound like a cacophony of rock, rap, and country-and-western tunes as males of all species croak and bellow for attention. So how does she find Mr. Right--and most importantly, Mr. Right Species? It turns out that she doesn't evaluate each call but rather blocks those that are biologically meaningless to her. Researchers already knew that female túngara frogs (Physalaemus pustulosus) that are ready to lay eggs and thus searching for mates pay more attention to the calls of their own species. Placed in a confined space and given a choice between a speaker emitting the "whine-chuck" of a túngara male or the call of another species, the females invariably hopped toward the túngara speaker. But male túngara frogs showed no such discrimination; they amped up their own calls whether they heard another túngara male or a male from another species. Kim Hoke, a neuroscientist at the University of Texas, Austin, suspected that males and females process the calls differently. To find out what part of the brain is involved, Hoke and colleagues tested 60 wild-caught túngara frogs (30 males and 30 females) that were ready for mating. Each frog listened for 30 minutes to a recording of a male túngara calling, to a different species, or to silence. They were immediately euthanized and their brains frozen and treated with a radioactive marker to reveal neural activity. © 2008 American Association for the Advancement of Science.

Keyword: Hearing; Sexual Behavior
Link ID: 11798 - Posted: 06.24.2010

No doubt about it, autism rates have skyrocketed in the U.S. and beyond in recent years. According to the Centers for Disease Control and Prevention, the disease affects one in every 150 children born today in the U.S., up from one in 500 as recently as just 10 years ago. It’s become the fastest-growing developmental disability—more prevalent than childhood cancer, juvenile diabetes and pediatric AIDS combined—and it continues to grow at a rate of 10 to 17 percent per year. While researchers think there is a genetic component to autism, they also believe environmental factors are playing a role in its recent increase. Environmental mercury and other heavy metal exposure, contaminated water, pesticides, a greater reliance on antibiotics—and even extensive television viewing by very young children—may be factors in mounting autism rates. Researchers at the American Academy of Pediatrics and other institutes have also identified flame retardants as possible culprits. Vaccines containing the mercury preservative thimerosal (now mostly removed from the market) have long been blamed for causing autism, but scientific links are inconclusive. In lieu of a smoking gun, a more complex picture of autism’s environmental causes is now emerging. Some researchers are focusing on the role of food in a young child’s development. Many autistic children suffer from digestive diseases or have genetic dispositions rendering them unable to naturally rid their bodies of toxins. As such, exposure to heavy metals, pesticides, contaminated water and even processed food could have a devastating cumulative effect, some researchers think. According to Brian MacFabe, a researcher at the University of Western Ontario who has studied autism triggers in rats, simple changes such as removing wheat and dairy from the diet could potentially bring about improvements. © 1996-2008 Scientific American Inc.

Keyword: Autism
Link ID: 11797 - Posted: 06.24.2010

Eric Bland -- The only definitive diagnosis of Alzheimer's disease is a brain slice from a cadaver -- which is obviously not much help for the living. But now a new laser that harmlessly penetrates deep into the live brain could help diagnose Alzheimer's before its most tragic effects are apparent. The laser won't treat the disease -- no cure for Alzheimer's exists -- but it could give scientists a better understanding of the disease, which could then lead to better treatments. "The ability to detect [Alzheimer's-linked brain plaques] early would be a great boon," said Eugene Hanlon, a doctor at the Veterans Affairs Medical Center in Mass. and co-author on the study that appears in Optics Express. "Doing therapy early on is when it would be most effective." There have been other physical diagnostics for Alzheimer's, such as lasers, MRI, and PET scans, but none of them have had the power to penetrate skin, bone and brain to find the protein groups that scientists think gum up neurons. The new system involves shining a near-infrared laser into the brain. When the light hits the protein clumps linked with Alzheimer's, the light scatters in a "distinctive" pattern that is the picked up by detectors, said Hanlon. Hanlon and his colleagues have tested the laser on brain tissue and hope to have a clinical trial involving live patients within a couple years. © 2008 Discovery Communications, LLC.

Keyword: Alzheimers
Link ID: 11796 - Posted: 06.24.2010

Daniel Cressey Fossilized fish provide a snapshot of evolution in action.NatureThe flatfish has always been regarded as an oddity. Although the immature fish has eyes on opposite sides of its head, one of the eyes migrates around its skull before it reaches maturity. Yet there was no evidence for this development process in the fossil record. Some evolutionary biologists, including Darwin, have argued that the trait evolved gradually over many generations of flatfish. If true, intermediate flatfish with partially offset eyes would once have lived — but no such fossils have ever been identified, giving succour to both creationists and those arguing for sudden jumps in evolution. But Matt Friedman, a PhD student studying evolutionary biology at the University of Chicago in Illinois, has now found three examples of these transitional forms. In the process, he unearthed an entirely new species of ancient flatfish in Vienna and re-interpreted already known fossil fish in London. His work is reported in this week's Nature1 (see video). Friedman says that the fossils are important because "they help to settle a long-standing evolutionary debate and shed light on the mode and tempo of evolutionary change". "From my standpoint as a palaeontologist and evolutionary biologist, I"m pleased that I've been able to showcase the power of fossil data in solving a problem that seemed so baffling from examining living diversity alone," he adds. © 2008 Nature Publishing Group

Keyword: Vision; Evolution
Link ID: 11795 - Posted: 06.24.2010

By Amy Maxmen Dopamine conducts a frenzied song of craving at one end of a tiny brain region and a panic-stricken hymn at the other. Depending on where along the length of the region the neurotransmitter is triggered, it elicits emotions ranging from desire to disgust, a new study shows. “The roles [of dopamine] may be partitioned, and perhaps defined, by anatomy,” comments Emily Hueske, a neuroscientist at the Massachusetts Institute of Technology. With the recent study, researchers have come one step closer to explaining how dopamine performs a spectrum of functions. Dopamine interacts with spatially coded signals so that its output varies from one end of a brain region to the other, the team reports in the July 9 Journal of Neuroscience. In the long-term, drugs might be developed to locally treat various dopamine-mediated disorders such as drug addiction, obsession, obesity and anxiety. Kent Berridge, a neuroscientist and psychologist at the University of Michigan in Ann Arbor, and his colleagues set out to understand how dopamine could lead to desire for a reward, and then turn around and cause fear, pain and stress. © Society for Science & the Public 2000 - 2008

Keyword: Drug Abuse; Emotions
Link ID: 11794 - Posted: 06.24.2010

Controlling blood pressure from middle-age onwards may dramatically reduce the chances of developing dementia, researchers have said. Two studies support a link between high blood pressure and dementia risk - with one by an Imperial College London team suggesting treatment could cut this. This study, by published in the Lancet Neurology journal, found blood pressure drugs reduce dementia by 13%. The Alzheimer's Society said better control could save 15,000 lives a year. As many as one in four people has high blood pressure, in many cases undiagnosed or untreated. The precise reasons why high blood pressure might increase the risk of dementia are not fully understood although many scientists believe that it can starve the brain of bloodflow and the oxygen it carries. Patients suffering this restricted bloodflow are often described as having "vascular dementia", and account for approximately a quarter of dementia patients. Other types of dementia, such as Alzheimer's disease, have no obvious link to bloodflow, but some experts think that blood pressure may still be somehow contributory in some cases. The Lancet Neurology study looked at a trial of elderly patients with high blood pressure to see if those who were receiving treatment were less likely to develop any form of dementia compared with those left untreated. The trial was stopped early after the benefits of treatment in terms of reducing strokes and heart disease were so obvious it became unethical to deny them to everyone. Although this meant that no benefits in terms of dementia could be found, when these results were combined with other similar studies in different age groups, the incidence of dementia was 13% lower in the treated groups. (C)BBC

Keyword: Alzheimers
Link ID: 11793 - Posted: 07.08.2008

By Joan Capuzzi Matthias was a playful, energetic dog with a penchant for chasing squirrels. He always knew his boundaries, though, thanks to the electric fence that has rimmed the yard for most of his life. But a couple of years ago, the aging English setter - he'll turn 15 tomorrow - stopped heeding that barrier. "He started wandering out of it," his owner, Vicki Sayles, recalls. "The shocks no longer seemed to bother him." Tests by the veterinarian ruled out various medical conditions that might have explained the behavior. Her diagnosis: cognitive dysfunction syndrome, more commonly known as dementia. First recognized in dogs in the early 1990s, the disease causes progressive cognitive and behavioral decline. Changes in the canine brain mirror those seen in people suffering from dementias such as Alzheimer's disease. Cats get dementia as well, though they are diagnosed less frequently, perhaps because felines are less social. Similar deterioration has been seen in the brains of aging rodents, sheep, goats, bears and primates. The changes in Matthias, subtle at first, became more pronounced. A lean, muscular blue belton bred from championship bloodlines, he was losing weight, urinating in the house, sleeping excessively, and withdrawing socially.

Keyword: Alzheimers
Link ID: 11792 - Posted: 07.08.2008

Parents might say a baby lights up their life, but a new study shows that an image of a smiling baby also "lights up" the reward centres of the mother's brain. Researchers wanted to find out more about the effects of different factors in child development, and made use of a functional magnetic resonance imaging machine to scan the moms' brains as they looked at photos of their own baby as well as unknown babies. "One of the most critical factors is the relationship an infant develops with the parent," said Dr. Lane Strathearn, assistant professor of pediatrics at Baylor College of Medicine and Texas Children's Hospital. "So I wanted to look at those factors more closely," he said in a phone interview from Houston. The researchers recruited 28 pregnant women in their final trimester who remained in the study for a year and a half. Strathearn said that several months after birth, the research team videotaped the babies, and extracted still images of their faces in all different stages of emotion — smiling, crying, neutral and everything in between. "And then we were able to use these images to present to the mothers while they were being scanned in the MRI scanner, to look at how their brains responded when they saw pictures of their own baby compared to a matched unknown baby that they'd never seen before," he said. © CBC 2008

Keyword: Emotions; Sexual Behavior
Link ID: 11791 - Posted: 06.24.2010

By Claire Panosian Dunavan When my friend Nikki Tal died in 2004, the world lost a strong, brave soul -- despite a thuggish disease that had by then utterly ravaged her body. From her earliest years, Nikki had been a reader. She also loved the ocean. Her favorite book was "Life of Pi," about a shipwrecked boy trapped on a raft with a hungry predator. The parallels with her own life weren't hard to see. Nikki's predator was amyotrophic lateral sclerosis, better known as ALS, or Lou Gehrig's disease. As any doctor will tell you, for patients with neurologic blights, ALS is about as bad as it gets. In less than a year, it can extinguish an entire set of motor neurons, rendering its victims limp and powerless. It was October 1996 when Nikki first learned something was wrong. While attending a baby shower, the 5-foot-8 lawyer realized she couldn't lift a 10-pound newborn. Later that month, she destroyed her car's ignition after repeatedly mis-inserting her key; then she begged off timing duty at her daughter's swim meets because she could no longer depress a stopwatch. A few months later came the inability to walk or care for herself; the big, padded wheelchair and the handicap van; and, eventually, the feeding tube and the portable ventilator. Finally, ALS robbed Nikki of the ability to hold her head erect and of producing even remotely intelligible speech. © 2008 The Washington Post Company

Keyword: ALS-Lou Gehrig's Disease
Link ID: 11790 - Posted: 06.24.2010

By NATALIE ANGIER WOODS HOLE, Mass. — It is summertime, when people everywhere honor the 40 percent of body mass devoted to skeletal muscle tissue by doing what they avoid doing the other 75 percent of the year — putting those muscles to strenuous, possibly dangerous use. They hike, bike and run very long distances, or they take up a new hybrid water sport like kitesurfing, which sounds sweet in concept but often looks embarrassing in execution. They may even make an inexcusably heroic sprint through four lanes of high-speed traffic, as my husband did the other day when the bicycle rack on our car broke and he decided he had to retrieve my instantly totaled bike from the middle of the interstate because, he said, “somebody could get hurt.” Yes, dear, like you, or the woman hyperventilating hysterically on the side of the road. This is why I argue that, when it comes to a sensible display of excessive muscular activity, the male toadfish has the right idea. A male toadfish may not look the part of an animal Olympian. He spends his time sitting nearly motionless on the bottom of a marsh, his body like a smeared scoop of pudding and old coffee beans, his full, fleshy lips pulled downward in a perpetual Churchillian scowl. Yet it turns out that inside the belly of this gelatinous, seemingly languorous beast are some of the fastest muscles in the vertebrate world, and the most instructive. Copyright 2008 The New York Times Company

Keyword: Animal Communication; Sexual Behavior
Link ID: 11789 - Posted: 06.24.2010

By Stephen L. Macknik and Susana Martinez-Conde How could we have missed it? Hundreds, perhaps thousands, of visual scientists, psychologists, neuroscientists, visual artists, architects, engineers and biologists all missed it—until now. The “it” in question is the Leaning Tower Illusion, discovered by Frederick Kingdom, Ali Yoonessi, and Elena Gheorghiu of McGill University. In this illusion, two identical side-by-side images of the same tilted and receding object appear to be leaning at two different angles [see slideshow]. This incredible effect was first noticed just last year in images of the famed Leaning Tower of Pisa, but it also works with paired images of other tilted objects. The Leaning Tower Illusion is one of the simplest visual tricks one can produce, but also one of the most profound to our understanding of depth perception. This fact is why vision scientists are shaking their heads in disbelief that they did not notice the illusion earlier. Kingdom and colleagues first announced the illusion at the 2007 Best Visual Illusion of the Year contest, where it won the First Prize. The annual contest, which we organized and which is hosted by the Neural Correlate Society, celebrates the ingenuity and creativity of the world’s premier visual illusion creators, both artists and scientists. Contestants submit novel visual illusions (that is, unpublished, or published no earlier than the previous year). An international panel of impartial judges conducts the initial review, and narrows the dozens of submissions down to the Top Ten best entries. The Top Ten creators then compete in Naples, Florida, during a gala celebration, in which the audience chooses the Top Three winners. First, Second and Third prizes take home the coveted “Guido” (a 3-D illusion sculpture created by the renowned Italian sculptor, Guido Moretti). © 1996-2008 Scientific American Inc.

Keyword: Vision
Link ID: 11788 - Posted: 06.24.2010