Even simple movements, such as picking up food to eat, can disappear when an accident or injury causes the loss of a limb or damage to the spinal cord. Now, following years of research, scientists have developed systems that can bypass the loss or damage by directly interpreting an animal's brain signals and launching movement in robotic limbs. The advances may lead to new ways to help disabled people regain mobility. Zip, zap, zing. Pure mental power propels a robotic arm to reach out and clutch an apple. This scenario once seemed more relevant to a science fiction movie script than a scientific study. But over the past three decades a better understanding of how the brain controls movement urged many scientists to seriously scrutinize the notion of thought-driven artificial limbs. Most recently researchers translated their knowledge into the development of systems that can interpret an animal's brain signals and launch movement in robotic devices. The new advances are leading to: Copyright © 2002 Society for Neuroscience

Keyword: Robotics
Link ID: 2010 - Posted: 06.24.2010

Exclusive from New Scientist Print Edition A little ground squirrel has revealed a slumbering secret of hibernating mammals. True hibernators, such as ground squirrels, marmots and chipmunks, regularly wake themselves from deep sleep. This didn't seem to make sense because it uses up huge amounts of valuable stored energy. But researchers have now found that they do it to fire up their immune systems and carry out a systems check for parasites and pathogens. Small mammals hibernate to conserve energy when food is scarce during long, cold winters. While larger creatures such as bears and badgers go into a state of torpor, in which their body temperature drops for short periods, true hibernators cool right down. Their temperature often drops as low as 5 °C for weeks on end. California's golden-mantled ground squirrel (Spermophilus lateralis ) is a champion hibernator. For five to six months each winter it spends most of the time with its heart ticking over at just two beats a minute. But roughly once a week, it wakes up and for 12 to 16 hours its body temperature rises to 37 °C. The wake-up periods use up to 80 per cent of the animal's winter energy budget. © Copyright Reed Business Information Ltd.

Keyword: Biological Rhythms
Link ID: 2009 - Posted: 06.24.2010

Susan Milius A Brooklyn-based research team has wired a rat's brain so that someone at a laptop computer can steer the animal through mazes and over rubble. The research gives a glimpse of the possibilities for training animals by sending cues and rewards directly to their brains, says Sanjiv Talwar of the State University of New York Downstate Medical Center. In the May 2 Nature , he and his colleagues predict their accomplishment could inspire novel approaches to land mine detection or search-and-rescue missions. The project grew out of research to develop new types of prostheses for paralyzed people that will use electric impulses sent directly to and from the brain. In 1999, coauthor John Chapin and his colleagues at the medical center demonstrated that signals from a rat's brain could move a robotic arm. From Science News, Vol. 161, No. 18, May 4, 2002, p. 276. Copyright ©2002 Science Service. All rights reserved.

Keyword: Robotics
Link ID: 2008 - Posted: 06.24.2010

— Researchers have discovered that astrocytes — brain cells once thought to be little more than a component of the supportive scaffold for neurons — may actually play a starring role in triggering the maturation and proliferation of adult neural stem cells. The studies also suggest that growth factors produced by astrocytes may be critical in regenerating brain or spinal tissue that has been damaged by trauma or disease. The discovery that astrocytes are important for neuronal maturation, or neurogenesis, was reported in the May 2, 2002, issue of the journal Nature by Howard Hughes Medical Institute investigator Charles F. Stevens and colleagues Fred H. Gage and HHMI research associate Hong-jun Song at The Salk Institute. Neurons are the key information-carrying cells in the central nervous system. All neurons, as well as other types of brain cells, arise from immature neural stem cells, which have the potential to develop into any kind of cell in the central nervous system. ©2002 Howard Hughes Medical Institute

Keyword: Glia; Regeneration
Link ID: 2005 - Posted: 06.24.2010

BOSTON(AScribe Newswire) -- In a study of suicidal behavior of 246 women with eating disorders over a span of 8.6 years, Debra L. Franko, an associate professor of counseling psychology at Northeastern University's Bouve College of Health Sciences, and her colleagues at Massachusetts General Hospital (MGH), found that women with anorexia nervosa are 57 times more likely to commit suicide than the expected rate for other women in the same age and racial groups. Eating disorder patients who are more psychiatrically ill were found to be at a greater risk to attempt suicide. Franko's research was chosen by the Academy for Eating Disorders to be presented at the International Conference on Eating Disorders, happening April 25-28 in Boston. In the 246 women studied at MGH, 51 women had anorexia nervosa restricting subtype (ANR), 85 women had anorexia nervosa, binge-purge subtype (ANBP), and 110 women had bulimia nervosa (BN). Four subjects (who were all diagnosed with anorexia nervosa at the start of the study) died by suicide, resulting in an elevated standardized mortality ratio of 56.9 for the anorexia nervosa subgroup. A total of 58 of the 246 subjects reported at least one suicide attempt during the course of the study, and of these, 32 made multiple attempts. Suicide attempts occurred in 21 percent of the ANR subjects, 31 percent of those with ANBP, and 19 percent of the BN sufferers.

Keyword: Anorexia & Bulimia
Link ID: 2004 - Posted: 05.04.2002

NewScientist.com news service Variations in a key gene might explain why some people turn to alcohol when they are stressed, a German study suggests. Mice lacking the gene started to drink three times more alcohol than normal mice after they suffered a stressful experience. Six months later, they still drank significantly more. The gene is for CRH1, a type of receptor in the corticotropin-releasing hormone system in the brain. This system mediates hormonal and behavioural responses to stress. The CRH1 receptor has previously been linked to stress-related psychiatric disorders. "Patients with alterations in this gene may be particularly susceptible to stress, and may respond with drinking," says Rainier Spanagel of the University of Heidelberg, who led the work. © Copyright Reed Business Information Ltd.

Keyword: Drug Abuse; Genes & Behavior
Link ID: 2003 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Romance in a relationship, such as unexpected phone calls, a surprise box of chocolates or a bouquet of flowers, may have more to do with biology than cupid's capriciousness. A new study suggests that men pour on the romance when women reach fertility peeks in their ovulation cycle as a strategy for keeping track of their mates and ensuring that they don't fall for other fellows. Findings are published in the current Proceedings of the Royal Society: Biological Sciences journal. Copyright © 2002 Discovery Communications Inc.

Keyword: Sexual Behavior; Evolution
Link ID: 2002 - Posted: 06.24.2010

It is often the quiet, supportive types who wield real power. Star-shaped brain cells called astrocytes, usually dismissed as support cells for the attention-grabbing neurons, now seem to control the growth of new neurons in adult brains. The find brings scientists closer to understanding the forces that control neuron growth in adults and could lead to ways to treat neurodegenerative diseases or spinal cord injuries. Astrocytes reside throughout the nervous system, filling in the spaces between neurons, the "wires" that pass the system's messages. Astrocytes were thought to constitute protective scaffolding and a nutrition source that help keep neurons healthy. But recently astrocytes have begun to shed their inert image. In the last few years, scientists have found that the supposedly placid cells help neurons form connections with each other (ScienceNOW, 26 January 2001) and might even be stem cells themselves (ScienceNOW, 15 June 1999). Copyright © 2002 by the American Association for the Advancement of Science.

Keyword: Glia; Neurogenesis
Link ID: 2001 - Posted: 06.24.2010

Females stray when mates lose song battles. JOHN WHITFIELD Female birds that overhear their partner lose a singing contest are more likely to mate sneakily with another male, researchers have found1. Just two defeats send a female looking for alternative mates. "Females are deciding who's going to father their children on the basis of a six-minute interaction," says zoologist Tom Peake of the University of Copenhagen, Denmark. "That's got to worry pretty much every male on the planet." Female eavesdropping shows that there's more to fighting than letting the combatants know who's boss - everyone within earshot is also picking up information. * Mennill, D. J., Ratcliffe, L. M. & Boag, P. T. Female eavesdropping on male song contests in songbirds. Science, 296, 873, (2002). © Nature News Service / Macmillan Magazines Ltd 2002

Keyword: Sexual Behavior
Link ID: 2000 - Posted: 06.24.2010

Scientists from The Center for Hearing and Balance at Johns Hopkins have discovered how tiny cells in the inner ear change sound into an electrical signal the brain can understand. Their finding, published in a recent issue of Nature Neuroscience, could improve the design and programming of hearing aids and cochlear implants by filling in a "black hole" in scientists' understanding of how we hear, say the researchers. "Sound itself is mechanical, a wave that moves, just like the ripples fanning out from a pebble dropped in a lake," says Paul Fuchs, Ph.D., professor of otolaryngology at the Johns Hopkins School of Medicine. "When the inner ear detects this wave, a burst of chemicals is released and a nerve sends an electrical signal to the brain that carries information about the original sound. But the nature of the chemical burst has been a mystery until now." Nature Neuroscience February 2002: 5 (2); 147-154.

Keyword: Hearing
Link ID: 1999 - Posted: 05.03.2002

Possible insight to multiple sclerosis and other neurodegenerative diseases that destroy nerve cell 'insulation' In the May 3 issue of Science, scientists at Rockefeller University and New York University School of Medicine report that the nerve damage that leads to a loss of sensation and disability of people with leprosy occurs in the early stages of infection. The nerve damage, a hallmark of leprosy previously thought to be a byproduct of the immune system’s response to the leprosy bacteria, now seems to be a direct result of the leprosy bug attaching itself to specialized nerve cells called Schwann cells, the glial, or supporting, cells of the peripheral nervous system (PNS). The findings suggest that the body’s immune response does not play a significant role in the early stage of neurological injury.

Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 1998 - Posted: 06.24.2010

In the first hours and days following a stroke, stem cells leave the bone marrow to help the injured brain repair damaged neurons and make new neurons and blood vessels, according to researchers at the Medical College of Georgia. The research, reported in the May issue of Stroke, used a mouse model in which the animal’s marrow was replaced with that of a transgenic mouse with cells that make a jellyfish protein that fluoresces green so they could trace the cells and the natural repair process that apparently occurs after stroke. The researchers are now looking for the right factors to enhance the normal repair mechanism, improve stroke recovery and, since the patient’s own cells would be used, avoid issues such as the compatibility of donated stem cells and the ethical controversy surrounding embryonic stem cells.

Keyword: Stroke; Stem Cells
Link ID: 1997 - Posted: 06.24.2010

Genetic test might identify ex-drinkers most likely to relapse under stress Why does stress make some people reach for a drink, but not others? Variations in a key stress-response gene may be at least one reason, suggests a German study on mice. The scientists report their findings in the journal Science, published by the American Association for the Advancement of Science. Rainer Spanagel of the University of Heidelberg and the Max Planck Institute of Psychiatry found that mice lacking the "CRH1" gene drank more alcohol than normal mice did after stressful experiences. If humans with variations in this gene behave the same way, a fairly simple test may identify recovering alcoholics likely to relapse under stress, according to Spanagel.

Keyword: Drug Abuse; Stress
Link ID: 1996 - Posted: 05.03.2002

Women are more likely to give up cigarettes if they take smoking cessation drugs rather than depend on nicotine replacement therapy, research suggests. A study by doctors at Oregon Health and Science University in the US found women who took the anti-smoking drug bupropion were more successful in kicking the habit. Bupropion is marketed as the anti-smoking drug Zyban. However, it is also prescribed as an anti-depressant under the name Wellbutrin. The authors believe the anti-depressant features of the drug may particularly benefit women who are more likely to start smoking again than men. They suggest the drug helps to relieve depression, irritability and other negative feelings which many women say leads them to take up the habit once more. (C) BBC

Keyword: Drug Abuse; Depression
Link ID: 1994 - Posted: 05.02.2002

By HOWARD MARKEL, M.D. Recently one morning, I received an urgent call from the mother of an 18-year-old named Daniel, whom I treat for marijuana abuse. For most of the past few years, Daniel had smoked more than a quarter of an ounce of marijuana daily and was almost always high, except, perhaps, when he was asleep. His marijuana problem has led to many others: he has been hospitalized, fired from jobs and thrown out of high school. He has faced run-ins with the police and lost the trust of most of his family members and friends. Copyright 2002 The New York Times Company

Keyword: Drug Abuse
Link ID: 1993 - Posted: 05.02.2002

Desire drives remote-controlled rodents. TOM CLARKE Remote-controlled rats could soon be detecting earthquake survivors or leading bomb-disposal teams to buried land mines. Signals from a laptop up to 500 metres away make the rats run, climb, jump and even cross brightly lit open spaces, contrary to their instincts. The rodents carry a backpack containing a radio receiver and a power source that transmits the signals into their brains through electrical probes the breadth of a hair. "They work for pleasure," says Sanjiv Talwar, the bioengineer at the State University of New York who led the research team. One electrode stimulates the rat's medial forebrain bundle, or MFB, the 'feelgood' centre of the mammalian brain. "The rat feels nirvana," Talwar says. Talwar, S. K. et al. Rat navigation guided by remote control.. Nature, 417, 37 - 38, (2002). © Nature News Service / Macmillan Magazines Ltd 2002

Keyword: Robotics
Link ID: 1992 - Posted: 06.24.2010

LITTLE ground squirrel has revealed a slumbering secret of hibernating mammals True hibernators, such as ground squirrels, marmots and chipmunks, regularly wake themselves from deep sleep. It didn't seem to make sense because this uses up huge amounts of valuable stored energy. But the answer seems to be they do it to fire up their immune systems and carry out a systems check for parasites and pathogens. Small mammals hibernate to conserve energy when food is scarce during long, cold winters. While larger creatures such as bears and badgers go into a state of torpor, in which their body temperature drops for short periods, true hibernators cool right down. Their temperature often drops as low as 5 ¡C for weeks on end. California's golden-mantled ground squirrel (Spermophilus lateralis) is a champion hibernator. For five to six months each winter it spends most of the time with its heart ticking over at just two beats a minute. But roughly once a week, it wakes up and for 12 to 16 hours its body temperature rises to 37 ¡C. The wake-up periods use up to 80 per cent of the animal's winter energy budget. Researchers wondered if the animals wake to clear waste from their body, but that seemed unlikely given the huge energy costs. To investigate, Brian Prendergast of Ohio State University at Columbus and his team took 31 squirrels into the lab and implanted them with radio transmitters that recorded body temperature every 5 seconds.

Keyword: Biological Rhythms; Neuroimmunology
Link ID: 1991 - Posted: 05.02.2002

DURHAM, N.C. -- A Duke University Medical Center pharmacologist is recommending caution when using the insecticide DEET, after his animal studies last year found the chemical causes diffuse brain cell death and behavioral changes in rats after frequent and prolonged use. Mohamed Abou-Donia, Ph.D. has also called for further government testing of the chemical's safety in short-term and occasional use, especially in view of Health Canada's recent decision to ban products with more than 30 percent of the chemical. Every year, approximately one-third of the U.S. population uses insect repellents containing DEET, available in more than 230 products with concentrations up to 100 percent. While the chemical's risks to humans are still being intensely debated, Abou-Donia says his 30 years of research on pesticides' brain effects clearly indicate the need for caution among the general public.

Keyword: Neurotoxins
Link ID: 1990 - Posted: 05.02.2002

The ability to learn a new language is determined by the onset of language experience during early brain development – regardless of the specific form of the language experience. This is the finding of a Canadian study led by Rachel Mayberry of McGill University. Mayberry, director of McGill’s School of Communication Sciences and Disorders, along with Elizabeth Lock of the University of Ottawa and Hena Kazmi of the University of Western Ontario, studied groups of deaf and hearing adults to see how the onset and type of initial language experience affects the ability to learn a new language. The results of the study, which will appear in the May 2 issue of the prestigious journal Nature, show that deaf and hearing adults who experience language in early life perform similarly well in learning a new language later in life – whereas deaf adults who had little language experience in early life showed low levels of performance in a later learned language. These findings are not affected by whether the early language or the later language was signed or spoken.

Keyword: Language; Development of the Brain
Link ID: 1989 - Posted: 06.24.2010

Copyright © 2002 Scripps Howard News Service By LEE BOWMAN, Scripps Howard News Service - Chin up, positive mental attitude, keep plugging along, don't let it get you down. Most aging experts - and most people - figure that being depressed, or anything but chipper, is a ticket toward illness and a shorter life. But a new study challenges this view with a finding that older women with mild depression actually live longer than women who aren't experiencing any symptoms of depression. Copyright © 2001 Nando Media

Keyword: Depression
Link ID: 1988 - Posted: 06.24.2010