Lola Crosswhite, 74, has battled Alzheimer's disease for more than five years. "I was just having a harder time hanging onto information and remembering things," she recalls of when she began to notice its onset. "It was sort of more of a feeling than anything else, of, 'Oh I've got to remember that, I've got to hang onto that'. I guess I had to acknowledge that I was just having a really hard time to remember things, and that wasn't much fun." Crosswhite was one of eight early-stage Alzheimer's patients who volunteered for brain surgery to inject genetically engineered cells taken from her skin into her brain back in 2001; it was the first-ever test of the safety of gene therapy for Alzheimer's. "It wasn't so much me as it was figuring that other people, or my children, would probably benefit from something that they would get from the study," says Crosswhite. "This clinical trial was the first step in determining whether we could safely deliver the growth factor using gene therapy to the human brain and if we could show that then to move on to subsequent trials that would really test its effectiveness," says Mark Tuszynski, neuroscientist at the University of California at San Diego, which conducted the trial. © ScienCentral, 2000- 2004.

Keyword: Alzheimers
Link ID: 5799 - Posted: 06.24.2010

When it's time to migrate, sparrows slash the amount of time they spend sleeping. But unlike long-haul truckers or college students cramming for exams, this avian insomnia may not take a serious toll on their cognitive skills. Understanding how the sparrows pull off this trick could provide a fresh insight into the nature of sleep. Each spring, the white-crowned sparrow, Zonotrichia leucophrys gambelii, sets off from its wintering site in Southern California on a 4300-kilometer migration to its breeding site in Alaska. During their wintering and breeding seasons, songbirds like this sparrow are active during the day and sleep at night. During migration however, they undergo a profound behavioral shift and fly both day and night. How the birds manage such a feat of endurance has remained a puzzle. Nobody knows, for example, whether migrating birds are able to take 40 winks on the wing. Research published 13 July in PLoS Biology suggests that they may not have to. To investigate the link between sleep and migration, Ruth Benca, a psychiatrist at the University of Wisconsin, Madison, turned to white-crowned sparrows. Instead of chasing migrating birds and watching them for signs of sleep, Benca kept an eye on captive birds when migration time rolled around. The birds become restless, Benca says, and her measurements of electrical activity in the birds' brains reveals that they sleep on average 63% less when it's time to migrate. A performance test, in which these hyperactive sparrows learn to peck on a sequence of buttons to earn seeds, suggests that they stay alert in spite of losing sleep. Understanding how they sleep less without impairment may provide insights into sleep disorders and seasonal mood disorders, she and her colleagues claim. That may be pushing things a bit far, says Ullrich Wagner, a neuroendocrinologist at the University of Lübeck in Germany, but the research does raise some intriguing questions. The birds' ability to get by without sleep is an "amazing phenomenon," he says, and future work should focus on the underlying mechanism. In the longer term, experiments like these could even shed light on the function of sleep itself, says Pierre Maquet, a neurobiologist at the University of Liège in Belgium, although he cautions that what's true for sparrows won't necessarily apply to humans. --HENRY NICHOLLS Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Sleep; Animal Migration
Link ID: 5798 - Posted: 06.24.2010

When we learn a new motor skill, we experience rapid improvement in motor performance during the initial training period and slowly improve with further training across subsequent days. Researchers at Duke University Medical Center now report evidence that certain neural circuits in the brain exhibit significant modulations in neuronal activity and connectivity during motor-skill learning and that distinct processes may mediate the neuronal changes that accompany the initial, fast phase of motor-skill learning compared to the longer-lasting, slower phase. Previous studies had revealed changes during motor-skill learning in neural activity and connectivity in several brain areas, namely motor cortex and dorsal striatum, but the nature and dynamics of the plastic changes in these brain structures during the different phases of motor learning remained unclear. In the new work, researchers Rui Costa, Dana Cohen, and Miguel Nicolelis at Duke University recorded the simultaneous neuronal activity in primary motor cortex and dorsolateral striatum of mice during the different phases of motor-skill learning. Neuronal activity was monitored in the mice as they learned, over multiple sessions, to remain on a rotating rod whose speed steadily increased. The researchers observed that cortico-striatal neural circuits undergo substantial changes during motor learning and found that this plasticity differs between fast and slow motor-skill learning. In addition, they discovered that during the initial fast, "within-session" learning, similar plastic processes evolved in parallel in motor cortex and dorsal striatum, whereas during slow, "across-session" learning, the activity changes in motor cortex and striatum differed. Perhaps somewhat surprisingly, these changes seemed to develop in the absence of alterations in the overall firing rate of the neuronal population in each brain area. These results may open interesting avenues for investigating the motor deficits observed in mouse models of neurodegenerative disorders, such as Parkinson's and Huntington's diseases.

Keyword: Learning & Memory
Link ID: 5797 - Posted: 07.14.2004

PITTSBURGH--Carnegie Mellon University neuroscientist Alison Barth has developed the first tool to identify and study individual neurons activated in a living animal. This advance, described in the July 21 issue of The Journal of Neuroscience, ultimately could lead to the development of targeted drugs that directly affect specific neurons involved in neurological diseases that alter behavior, learning and perception. While neuroscientists have made great strides in identifying the general areas of the brain that perform certain tasks, these methods have worked at the gross level and with poor resolution, according to Barth, an assistant professor of biological sciences at the university's Mellon College of Science. To overcome these limitations, Barth created a transgenic mouse that couples the green fluorescent protein (GFP) with the gene c-fos, which turns on when nerve cells are activated. Using this method, researchers can see specific neurons glow as they are activated by external stimuli such as sensory experience or drug treatment. "Our transgenic mouse is a novel tool that can be used to visualize, in living brain tissue, a single neuron that has been activated in response to an animal's experience," Barth said. Barth used the fosGFP mice to identify neurons that are activated during a specific rearing condition – experiencing the world through one whisker. By locating a cluster of glowing neurons, she was able to precisely identify the area of the brain involved in processing sensory input from the single whisker.

Keyword: Brain imaging
Link ID: 5796 - Posted: 06.24.2010

TUESDAY, (HealthDayNews) -- It's sure to be music to parents' ears: After nine months of weekly training in piano or voice, new research shows young students' IQs rose nearly three points more than their untrained peers. The Canadian study lends support to the idea that musical training may do more for kids than simply teach them their scales -- it exercises parts of the brain useful in mathematics, spatial intelligence and other intellectual pursuits. "With music lessons, because there are so many different facets involved -- such as memorizing, expressing emotion, learning about musical interval and chords -- the multidimensional nature of the experience may be motivating the [IQ] effect," said study author E. Glenn Schellenberg, of the University of Toronto at Mississauga. A decade ago, researchers led by the University of Wisconsin's Frances Rauscher found that simply listening to Mozart triggered temporary increases in spatial intelligence. While the "Mozart Effect" has proven difficult to replicate in subsequent studies, the idea that music or musical training might raise IQ took hold in the scientific community. In his study, slated for publication in the August issue of Psychological Science, Schellenberg offered 12 Toronto-area 6-year-olds free weekly voice or piano lessons at the Royal Conservatory of Music, described by Schellenberg as Canada's "most prestigious music conservatory." Copyright © 2004 Yahoo! Inc.

Keyword: Intelligence; Hearing
Link ID: 5795 - Posted: 06.24.2010

By ROBIN MARANTZ HENIG Am I the only person who still prefers doing things one at a time? My fellow New Yorkers have raised multitasking to an art form. People talk on their cellphones while jogging, do their homework on the subway, listen to books on tape while walking, put on makeup in the back seat of the taxicab and - always, everywhere, constantly - talk on their cellphones while they're busy doing something else. This isn't how things were meant to be. Our brains are not built to work this way, no matter how many times teenagers insist that they're paying full attention to their homework, despite the fact that they're also watching television, listening to music and sending electronic instant messages to friends who are doing their own homework amid comparable chaos. The brain works best "on a single task and for sustained rather than intermittent or alternating periods of time," the neurologist Richard Restak writes in "The New Brain: How the Modern Age Is Rewiring Your Mind." "This doesn't mean that we can't perform a certain amount of multitasking,'' Dr. Restak writes.. "But we do so at decreased efficiency and accuracy." Copyright 2004 The New York Times Company

Keyword: Attention
Link ID: 5794 - Posted: 07.14.2004

By SANDRA BLAKESLEE A century ago, neurologists noticed that when ladies wearing big feathered hats ducked through entryways, they would align their bodies just so. It was as if they could feel the tops of doors with the tips of the feathers. From this and other observations, the scientists concluded that each person holds within the brain a mental representation of the body and its parts - even the clothing it wears - as it moves through space. Those early scientists could not explain how the brain creates such sensations, or body schemas. But using modern methods for probing brains, researchers are uncovering the cells and circuits that are responsible. For example, research has found that brain cells become active as objects approach the space around the body. These cells will fire when, say, you see an insect fly toward your face. This so-called peripersonal space extends to arm's length; people with longer arms have a bigger peripersonal space. And when they use a tool, a rake, a joystick or an automobile, their body schema and peripersonal space expand to include it. Copyright 2004 The New York Times Company

Keyword: Vision
Link ID: 5793 - Posted: 07.14.2004

BY BRIAN BRUEGGEMANN It sounds like something from a soap opera. Jim Schauster drives 4,000 miles, feeds himself during the nearly three-week trip, checks into a hotel for at least one night, drives back home, then doesn't remember any of it. Experts on amnesia say it sounds as if Schauster may have experienced a phenomenon known as a fugue state -- an amnesic event where a person functions in a sort of twilight zone. "They travel long distances in these states, and they don't realize where they've been until they come around and they see that they've got a ticket or a hotel bill or something on them," said Dr. Michael Kopelman of London, one of the world's top experts on memory loss. Kopelman said he sees two or three patients a year who arrive in London with no idea who they are or why they're there. He said they usually snap out of it due to "some chance cue in the environment," such as one patient who saw a book title that reminded him of a friend. Schuaster, 53, of Highland had been missing since June 18, when he showed up Tuesday morning at St. Joseph's Hospital in Highland. He said he was driving and realized he was in nearby St. Jacob, but he didn't know why, so he went straight to the hospital. Lt. John Lakin of the Madison County sheriff's department said police have no reason to doubt him.

Keyword: Learning & Memory
Link ID: 5792 - Posted: 07.14.2004

By Rob Stein, Washington Post Staff Writer For decades, scientists thought fat cells were passive blobs that did nothing more than store energy, bloat flabby hips and bellies, and perhaps wear down the body by forcing it to cart around a lot of extra weight. But as the nation's obesity crisis has intensified scientific interest in fat, researchers have fundamentally altered that view: Fat cells, they now realize, are extraordinarily dynamic, complex and influential entities that affect a staggering array of crucial bodily functions. The new insights into fat's commanding, self-sustaining powers, scientists say, have profound implications for understanding how flab forms, why it hangs on so stubbornly, how it causes disease, and therefore possibly how to help people shed pounds and avoid the devastating health problems wrought by fat cells. "They were always thought to be poor, dumb sacks of lard," said Roger Unger, an obesity researcher at the University of Texas Southwestern Medical Center. "It turns out that they end up being very talented, very versatile, very important players." © 2004 The Washington Post Company

Keyword: Obesity
Link ID: 5791 - Posted: 06.24.2010

US scientists believe nerve cells critical for gasping offer important clues to the cause of cot death. Dr Jan-Marino Ramirez and colleagues at the University of Chicago have found two brain cell pathways that drive breathing baby mice. Normally, one pathway will compensate if the other is blocked, causing the baby to gasp to take in air. Cot deaths may occur if both pathways become blocked for some reason, say the authors in the journal Neuron. Normally, if a baby becomes short of oxygen for any reason they will gasp. Dr Ramirez's team had previously shown a specific group of pacemaker neurons in the brain controlled gasping in baby mice. They had thought all of the neurons communicated in the same way, via sodium channels. However, when scientists used a drug that blocks sodium they found only some of the neurons stopped communicating. According to Dr Raminez this meant there must be two pathways that instructions to make the baby gasp. (C)BBC

Keyword: Sleep
Link ID: 5790 - Posted: 07.14.2004

By ANDREW POLLACK Amgen's anemia drug, the best-selling product developed so far by the biotechnology industry, might have broad new uses, recent studies have found. Laboratory and animal studies have shown that in addition to bolstering the body's red blood cells, the drug, EPO, is present in the central nervous system and acts to protect cells and tissues from damage and death. That could make it useful as a treatment for strokes, spinal cord injuries, multiple sclerosis and many other ailments. Testing in humans is in very early stages. A small study by academic scientists in Germany found that EPO, when given within eight hours of a stroke, helped protect the brain from damage and improve patient recovery. A larger trial is now under way there. Another early-stage trial in Germany is testing EPO as a treatment for schizophrenia, and in the United States, academic scientists are planning trials for AIDS-related dementia and for a nerve disease similar to multiple sclerosis. EPO, short for erythropoietin, is sold by Amgen as Epogen and, in a newer form, as Aranesp. Johnson & Johnson, under license from Amgen, sells it under the names Procrit and Eprex. The versions had combined sales of $8 billion last year. Copyright 2004 The New York Times Company

Keyword: Stroke; Regeneration
Link ID: 5789 - Posted: 07.10.2004

Carrie Lock Next time you can't make out a distant highway sign, blame your parents. Scientists in the United Kingdom have found that myopia, or nearsightedness, is predominantly hereditary, and they're beginning to unravel the genetic mechanism that causes the vision problem. Roughly a third of people in the United States suffer from myopia—they clearly see close objects, such as words in a book, but things in the distance appear blurry. The anatomic root of the problem is an elongation of the eye as it grows, causing incoming light to focus in front of the retina, instead of squarely on it, explains Christopher J. Hammond of St. Thomas' Hospital in London. Using a noninvasive technique, Hammond measured the sizes of the eyeballs of 280 sets of fraternal adult twins and 226 sets of identical twins. By mathematically modeling the differences in the eye sizes, Hammond found that genes accounted for 89 percent of nearsightedness, farsightedness, and other refractive vision problems, he reports in the August American Journal of Human Genetics. Copyright ©2004 Science Service.

Keyword: Vision
Link ID: 5788 - Posted: 06.24.2010

Scientists at the National Institute of Dental and Craniofacial Research (NIDCR), one of the National Institutes of Health, and their colleagues have isolated human postnatal stem cells for the first time directly from the periodontal ligament, the fibrous, net-like tendon that holds our teeth in their sockets. The scientists also say these cells have "tremendous potential" to regenerate the periodontal ligament, a common target of advanced gum (periodontal) disease. This enthusiasm is based on follow up experiments, in which the researchers implanted the human adult stem cells into rodents, and most of the cells differentiated into a mixture of periodontal ligament — including the specific fiber bundles that attach tooth to bone — and the mineralized tissue called cementum that covers the roots of our teeth. "The stem cells produced beautifully dense, regenerated tissue in the animals," said Dr. Songtao Shi, a senior author on the paper and an NIDCR scientist. "That was when we knew they had great potential one day as a treatment for periodontal disease, and we're continuing to follow up on this promise with additional animal work." The results are published in the current issue of The Lancet. Shi said scientists have suspected since the 1970s that the periodontal ligament might contain its own unique stem cells. But, for a variety of technical reasons, the search had come up empty, leaving some to wonder whether stem cells could be extracted from such a tiny bit of tissue known to contain a confusing mixture of cell types and subsets.

Keyword: Stem Cells; Regeneration
Link ID: 5787 - Posted: 06.24.2010

It looks like a fat carrot, but it is actually a banana. And it is so rich in precursors to vitamin A that researchers hope it could prevent children from going blind in the Pacific islands of Micronesia. Dubbed the "karat" because of its bright orange flesh, the unusual banana has been used for centuries in Micronesia to wean infants onto solid food. But today it is rarely eaten there, as imported foods have grown in popularity. The "karat" had been used for centuries in Micronesia to wean infants (Image: Lois Englberger, University of Queensland, Aus) That now looks set to change. A screening programme sponsored by the agriculture ministry of Pohnpei, a Micronesian island, has established that the karat is unusually rich in beta-carotene, which the body converts into vitamin A. The hope is that the fruit could now be routinely given to children deficient in this vitamin, to help them avoid developing certain kinds of blindness. © Copyright Reed Business Information Ltd

Keyword: Vision
Link ID: 5786 - Posted: 06.24.2010

Helen Pilcher Machines that can be controlled by the mind have moved a step closer to reality. Researchers have trained monkeys to 'think' a cursor around a computer screen to reveal their preferences and goals. It is hoped the technology will lead to devices that can display the thoughts of paralysed people who are unable to communicate through speech or sign. It could also aid the development of artificial limbs and robots that are operated by the brain alone. In the past couple of years, researchers have already developed chips that recognise brain signals for movement and convert them into action. Monkeys fitted with the devices have been trained to move cursors around monitors. Such devices translate signals from the brain's motor cortex, the region that directs physical movement. But now Richard Andersen from the California Institute of Technology, Pasadena, and colleagues have decoded signals from a different region, the parietal cortex, which helps us plan our actions. Their study is published in Science1. ©2004 Nature Publishing Group

Keyword: Vision; Robotics
Link ID: 5785 - Posted: 06.24.2010

By HENRY FOUNTAIN Everybody's got rhythm - circadian rhythm, that is. From the most multicellular of creatures (humans included) to single-cell bacteria, many organisms display activities and behavior that oscillate precisely with daily cycles of light and dark. Almost nobody has perfect rhythm. In a multicellular organism, the circadian clocks of individual cells may be slightly out of whack. Communication among cells, however, allows them to synchronize so that the organism's precise rhythm is maintained. But what about bacteria? Colonies have been shown to have precise circadian cycles by which genes express certain compounds. But is that because communication adjusts the variations among individual organisms? Or are the individual clocks more accurate? Dr. Irina Mihalcescu of Joseph Fourier University in France has answered that question, at least for a certain kind of bacteria - cyanobacteria, or blue-green algae. These organisms, she and colleagues report in the journal Nature, are like Swiss watches. Their circadian rhythms are extremely precise. Copyright 2004 The New York Times Company

Keyword: Biological Rhythms
Link ID: 5784 - Posted: 07.09.2004

Cockroaches, perhaps the most unpopular of all unwelcome insect houseguests, have probably been around for 280 million years, and they'll probably still be around after we're gone. These speedy, hearty critters are almost indestructible—they can even live for a whole week without their heads. Roaches are a source of disgust for most of us. But Mark Cutkosky, mechanical engineer and co-director of the Center for Design Research at Stanford University is proving that one man's frustration is another man's inspiration. Cutkosky and his research group, along with Robert Full, biomechanics professor and director of the Poly-PEDAL lab, and his team at the University of California at Berkeley, designed the Sprawl family of legged robots based on the way roaches move (AKA "bio-inspired"). "Roaches, if you want to do small things that run fast, are a pretty good exemplar," says Cutkosky. "They're very robust, they move remarkably fast—20, 25 even up to 50 body lengths per second for the American cockroach. That's much faster per scale-to-size than you and I can run. They're very stable and they run with a very simple control system." © ScienCentral, 2000- 2004.

Keyword: Robotics
Link ID: 5783 - Posted: 06.24.2010

Henry Gee How could sophisticated mechanisms such as the flagellar motor or the adaptive immune system have evolved without some guiding hand? Henry Gee finds his answer to the argument of Intelligent Design in the lamprey. We are accustomed to thinking of ourselves as peaks of perfection, and the arrangements of more "primitive" creatures as similar to our own, only cruder. It's a nice idea. Until along comes the sea lamprey to challenge our preconceptions. Researchers have found that the lamprey (Petromyzon marinus) has a has a sophisticated system of adaptive immunity, that is entirely different to our own. Many organisms have a kind of natural immunity, but the adaptive immunity of mammals was supposed to be something special. By dint of a kind of controlled chaos, specialized parts of our genomes rearrange themselves to produce antibodies, custom-built proteins that are then selected to target any kind of foreign molecule the world can throw at us. One of the great mysteries of immunology is how and when this remarkable system originated. For many years, immunologists looked for its beginnings in lampreys, sucker-mouthed creatures that represent the earliest flourish of vertebrate evolution more than 500 million years ago. Lacking jaws and paired fins, lampreys are almost as primitive as a vertebrate can get. They seem to have adaptive immunity, but scientists haven't found even a glimmer of any antibodies. ©2004 Nature Publishing Group

Keyword: Evolution
Link ID: 5782 - Posted: 06.24.2010

By ROWAN HOOPER Everyone knows someone who is a compulsive womanizer; a man who simply can't remain faithful to one woman. Likewise, everyone knows someone who is a doting, faithful husband; for such a man the idea of sex with women other than his partner is unthinkable. Ever wondered why men are so different? Scientists working on one of the few other mammal species to form a pair bond have found the beginnings of an answer. Miranda Lim and colleagues at the Center for Behavioral Neuroscience, Emory University, Atlanta, Ga., have focused their research on prairie voles, one of the few mammal species that are monogamous and form lifelong pair bonds. They chose prairie voles as their study species because there is a closely related species that, although very similar genetically, exhibits very different social behavior. While the male prairie vole is monogamous, the male meadow vole is polygamous. And by changing just one gene in the meadow vole, the biologists reversed its polygamy: They turned the "love rat" into a cuddly, loving little rodent. The Japan Times 2004 (C) All rights reserved

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 5781 - Posted: 07.09.2004

BERKELEY – Organisms ranging from bacteria to humans navigate environments that can contain dangerously too little or too much oxygen. Yet, scientists know little about how animals sense oxygen levels around them. Researchers from the Berkeley and San Francisco campuses of the University of California have now discovered how the nematode C. elegans senses oxygen levels in order to steer clear of surrounding areas that are too low or too high in oxygen. In the process, the researchers also discovered that the worm doesn't like as much fresh air as people thought. While nematodes grown in laboratory Petri dishes are kept at the same oxygen concentration humans breathe in ambient air - 21 percent - nematodes appear to prefer only 6 percent oxygen. "It was totally unexpected that they would actually prefer 6 percent. We don't know why, though it probably gives them some survival advantage," said Michael A. Marletta, professor of chemistry and of molecular and cell biology at UC Berkeley, and a faculty scientist at Lawrence Berkeley National Laboratory (LBNL). "And the bordering and clumping that worm experts refer to as social behavior is really the worms, in an artificial setting like a Petri dish, trying to get to an area of 6 percent oxygen, which they like. It's a laboratory phenomenon." Copyright UC Regents

Keyword: Chemical Senses (Smell & Taste)
Link ID: 5780 - Posted: 06.24.2010