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Scranton, Pa. -- Teaching sign language to hearing young children can improve their early communications with their parents and later boost the children's learning of language, says a Penn State researcher. "When you see babies, you can see them experiment with their hands. They move them about, they touch their hands together, they try to reach things, they attempt to pick up objects, " says Dr. Marilyn Daniels, associate professor of speech communication at Penn State's Worthington Scranton Campus. "Sign language has the unique capacity to tap into the natural exchange between hand and brain, optimizing the emergence of language in the child because of the physiological advantage of American Sign Language (ASL) over English." Learning to speak, read and write English takes years, much patience and practice for young children. But they effortlessly use their hands for comfort, communication and acquiring information from birth, says Daniels.

Keyword: Language; Development of the Brain
Link ID: 1019 - Posted: 11.22.2001

Associated Press PITTSBURGH - After three months in space, astronauts lose sleep and sleep less soundly because the lack of gravity and the absence of day-and-night cues throw off their internal clocks, according to the first long-term study of the topic. The phenomenon could leave astronauts less alert and hamper performance on longer trips, according to the study, published in the December issue of the journal Psychosomatic Medicine. Space sleeplessness is apparently caused by changes in the brain's endogenous circadian pacemaker -- a bundle of nerve cells the size of a pinhead that controls the body's cycle of sleep and wakefulness

Keyword: Sleep
Link ID: 1015 - Posted: 11.22.2001

Criminal behaviour suggests birds' brains are more sophisticated than we thought. TOM CLARKE American scrub jays with a history of petty theft are more concerned about being victims of crime than are innocent birds, new research shows. This suggests that the animals may use the past to predict the future and might put themselves in another's shoes - two mental feats so far attributed only to humans. "Until recently we thought that animals were stuck in time," says Nicola Clayton, a psychologist at the University of Cambridge in England. By observing captive jays bury and retrieve food in the presence and absence of fellow jays, Clayton and her behavioural scientist husband Nathan Emery find that the birds perform 'mental time-travel': they apply the lessons of past events to future behaviour. Emery, N. J. & Clayton, N. S. Effects of experience and social context on prospective caching strategies by scrub jays. Nature, 414, 443 - 446, (2001). © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Learning & Memory
Link ID: 1014 - Posted: 11.22.2001

If your friends were normal people they would not know you. PHILIP BALL "Your friends are unusual people", says physicist Mark Newman: simply because they are someone's friend. This is not some homespun philosophy to make us all feel better. Newman, of the Santa Fe Institute in New Mexico, USA, has proved that our friends are not a random selection of the population1. If they were, the chance that you and I share a friend of a friend would be much smaller than it is. Newman is exploring social networks. More specifically, he wants to know what the chances are that we have a friend of a friend who supports Real Madrid or the New York Giants. Or who went to Florence last summer. Or who likes water polo. Newman, M. E. J. Ego-centered networks and the ripple effect, or Why all your friends are weird. Preprint, (2001). © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Miscellaneous
Link ID: 1013 - Posted: 11.22.2001

Emma Young, San Diego
The devastating sleep disorder narcolepsy could be the result of a sufferer's immune system attacking key cells in the brain, say US scientists. Jerry Siegel at the University of California, Los Angeles and his team gave commonly used immune system suppressants to dogs with a genetic mutation that makes them develop narcolepsy. They found that the onset of the disease was dramatically delayed. Furthermore, when symptoms did appear, they were also much less severe. "The immunosuppressants in dogs produced a reduction in symptoms that is quite remarkable," Siegel says. "It is quite likely that a similar treatment could be effective in humans if we could detect symptoms at an early stage." © Copyright Reed Business Information Ltd.

Keyword: Narcolepsy; Sleep
Link ID: 1012 - Posted: 11.17.2001

John Travis While cholesterol has a bad reputation for clogging up arteries and causing heart disease, this fatty molecule is an essential part of all cell membranes. Scientists have now found to their surprise that cholesterol may also regulate when and where nerve cells in the brain form the vital junctions known as synapses. Equally unforeseen, say investigators, is their finding that non-nerve cells called glia seem to provide the cholesterol that controls synapse building. Glia make up 90 percent of the cells in the brain, but they have traditionally drawn less interest than have nerve cells, or neurons, which relay electrical signals by releasing chemicals at synapses. Barres, B.A., and S.J. Smith. 2001. Cholesterol-Making or breaking the synapse. Science 294(Nov. 9):1296-1297. From Science News, Vol. 160, No. 20, Nov. 17, 2001, p. 309. Copyright ©2001 Science Service. All rights reserved.

Keyword: Glia
Link ID: 1009 - Posted: 11.17.2001

PHILIP BALL Scientists in the United States are soldering nerve cells to semiconductors. Christine Schmidt and colleagues from the University of Texas at Austin use a sliver of protein to connect neurons and tiny crystals of semiconductors called quantum dots1. This cross between biology and electronics could have useful applications, including the manufacture of prosthetics operated directly by a user's nerve impulses, and sensors that detect tiny quantities of neurotoxins. It could also help to study how real brains work. Winter, J. O., Liu, T. Y., Korgel, B. A. & Schmidt, C. E. Recognition molecule directed interfacing between semiconductor quantum dots and nerve cells. Advanced Materials, 13, 1673 - 1677, (2001). © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Robotics
Link ID: 1008 - Posted: 11.17.2001

SAN DIEGO--Just as we have to crawl before we walk, before we can talk we have to babble. Many researchers think babbling babies are merely learning to move the muscles involved with speech. But research presented here 13 November at the Society for Neuroscience meeting indicates that there may be more to babbling than meets the ear: It originates in the brain's language centers. The brain deals with language in its left hemisphere, and because the left half of the brain controls the right side of the body, most adults speak using the right side of their mouths more than the left side. Dubious? Watch people's mouths while they talk and you can see it for yourself. Though some people don't follow the pattern--just as some people are left-handed--right-mouthers are the rule. If babbling is just a function of babies exercising their mouth muscles, it shouldn't preferentially draw on the language half of the brain, and babies should babble out of both sides of their mouths. Copyright © 2001 by the American Association for the Advancement of Science.

Keyword: Language; Development of the Brain
Link ID: 1007 - Posted: 11.17.2001

University of Georgia scientists have discovered a protein in fire ants that may lead to a new way of using their own biology against them. The protein is linked to red imported fire ants' senses of smell and taste. The research appears today in the journal Science. "We discovered two variants of a protein found in fire ants and noticed that one was found only in multiple-queen colonies," said Ken Ross, an entomologist with the UGA College of Agricultural and Environmental Sciences. "That's what peaked our interest two and a half years ago," Ross said. "It made us wonder whether this protein could affect the social behavior and structure of the colony."

Keyword: Animal Communication; Chemical Senses (Smell & Taste)
Link ID: 1006 - Posted: 11.17.2001

Neuroscientist David Linden, Ph.D., is excited about his latest research findings, even though the experiments' results echo his four-year-old son's tendency to answer questions with a resounding "No, no, no." But in science, sometimes figuring out what isn't happening can be very telling, says Linden, whose report will appear in the Nov. 13 issue of the Proceedings of the National Academy of Sciences. "It may sound dull because the answers are all 'no,' but it's actually exciting, because there's just one possibility left and we've already seen evidence for it," he says. Linden is studying what brain cells do to retain a new memory. Scientists have shown that learning happens when a brain cell gets stimulated in a way that reduces its ability to respond to a particular brain messenger called glutamate. "We have the 'wiring diagram' for some simple forms of motor learning, so we know how memories get stored in the circuit because we know which cells receive the stimulation and how they pass it along," explains Linden. "Now we're using that wiring diagram to look at the details." Linden is studying strange, sea-fan-shaped brain cell called Purkinje cells (pronounced per-KIN-jee). These odd cells are found only in the cerebellum, a part of the brain involved in coordinating and learning muscle movement patterns.

Keyword: Learning & Memory
Link ID: 1004 - Posted: 11.16.2001

In a discovery that demonstrates a clear link between the mind and body at a molecular level, scientists have shown that a chemical signal which normally allows nerve cells to communicate with each other - to alter sleep cycles, for example -- can also re-direct actions of the immune system. The research in mice confirms mounting evidence from studies of cultured cells that the nervous system directly influences the immune system. It has prompted new experiments to determine if the nerve-generated signal or its receptors in the immune system might make good drug targets to control asthma or allergies. "This is the first clue of a practical pharmacological approach to using the nervous system for both improving immune defenses and damping harmful immune responses at their roots in diseases as diverse as arthritis and asthma," said Edward Goetzl, MD. Copyright 2001 Regents of the University of California. All Rights Reserved.

Keyword: Neuroimmunology
Link ID: 1003 - Posted: 11.16.2001

JOHN WHITFIELD A protein that spots smell controls the power structure of fire ant colonies, Michael Krieger and Kenneth Ross of the University of Georgia, Athens, have discovered1. One form of the protein leads to nests with several queens living in harmony. The other leaves only one ruler. Fire ants' social life is of more than academic interest. The species (Solenopsis invicta) has spread from its South American homeland to become a serious pest in the Southern United States. 1.Krieger, M. J. B. & Ross, K. G. Identification of a major gene regulating complex social behaviour. Science in the press (2001). © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Genes & Behavior; Animal Communication
Link ID: 1002 - Posted: 11.16.2001

Emma Young, San Diego Early maternal neglect changes the expression of genes involved in the development of the dopamine system, research on mice has revealed. Abnormal regulation of dopamine in the brain has been linked to drug abuse, depression and personality disorders - conditions that are also associated with childhood neglect in humans. "Clearly, if the dopamine system of the brain is compromised, and if this can be extrapolated to humans, it could lead to greater susceptibility for drug dependence and perhaps greater vulnerability to develop certain psychiatric illnesses," says researcher Wayne Brake of the University of California, Santa Barbara.

Keyword: Development of the Brain
Link ID: 1000 - Posted: 11.16.2001

Men's and women's brains are different Women's brains are more tightly packed with cells in the area that controls mental processes such as judgement, personality, planning and working memory, researchers have discovered. A team from McMaster University, Ontario, Canada, found that women have up to 15% more brain cell density in certain areas of the frontal lobe, which controls so-called higher mental processes. The cells are found in areas that make connections with other parts of the brain, such as the limbic system which is thought to play a major role in the emotions. (c) BBC

Keyword: Sexual Behavior
Link ID: 997 - Posted: 11.15.2001

ERICA KLARREICH People who lack a gene involved in immune responses may be three times more likely to suffer from variant Creutzfeldt-Jakob disease (vCJD), a new study suggests1. The result, if borne out in larger studies, could point researchers toward therapies for the incurable brain disease. vCJD is thought to occur when people are exposed to misshapen prion proteins from cows with bovine spongiform encephalopathy - BSE or 'mad cow disease'. The gene does not appear to protect against the sporadic form of the disease (CJD). 1.Jackson, G. S. et al. HLA-DQ7 antigen and resistance to variant CJD. Nature, 414, 269 - 270, (2001). © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Prions; Genes & Behavior
Link ID: 996 - Posted: 11.15.2001

Animals may sniff out the mate with the most varied genes. ERICA KLARREICH In underwater courtship, smelling fishy can attract a ladylove more successfully than a bouquet of algae or a gift-wrapped box of brine shrimp. A new study finds that female stickleback fish prefer the scent of males with the most diverse array of genes in a part of the genome dedicated to fighting disease, called the major histocompatibility complex (MHC)1. Apparently, a finely tuned mechanism enables fish to smell the mate that will give them the fittest offspring. © Nature News Service / Macmillan Magazines Ltd 2001

Keyword: Chemical Senses (Smell & Taste); Sexual Behavior
Link ID: 995 - Posted: 11.15.2001

A unique genetic change associated with the development of early-onset Alzheimer's disease in Caribbean Hispanics has been identified by Columbia University College of Physicians & Surgeons researchers. This newly recognized variation in the presenilin 1 gene also seems to trace back to a common ancestor. The finding should allow physicians to use mutation analysis to better diagnose the neurodegenerative disease in certain families of Caribbean Hispanic heritage and to genetically counsel family members with a familial risk for the disorder, the researchers say. The investigators, led by Dr. Richard Mayeux, director of the Gertrude H. Sergievsky Center and co-director of the Taub Institute on Alzheimer's Disease, are publishing the results of their study in the Nov. 14 issue of the Journal of the American Medical Association.

Keyword: Animal Communication; Genes & Behavior
Link ID: 994 - Posted: 11.15.2001

(Embargoed) CHAPEL HILL – Although scientists have known for years that cocaine, marijuana and heroin interact with specific proteins in the brain, traditionally they have thought alcohol had no such pointed effects. Now University of North Carolina at Chapel Hill researchers have found evidence that alcohol inhibits the actions of key proteins called N-methyl-D-aspartic acid (NMDA) receptors in specific regions of the brain. A report on their work appears Thursday (Nov. 15) in the November issue of the journal Alcoholism: Clinical & Experimental Research. "NMDA receptors in the brain are key sites of action of the neurotransmitter glutamate, which increases the activity of brain neurons," said lead author Dr. Darin J. Knapp,

Keyword: Drug Abuse
Link ID: 993 - Posted: 06.24.2010

Scientists have identified for the first time specific genes in the brain that are affected by the lack of FMRP - the protein that is absent in individuals with fragile X syndrome, the most frequent cause of inherited mental retardation in humans. The finding, published in the Nov. 16 issue of the journal Cell, provides the first clear evidence that fragile X syndrome may be caused by the dysregulation of specific mRNA (messenger RNA) molecules and their encoded proteins. The research group included scientists from Emory University, the Rockefeller University, Duke University and the Howard Hughes Medical Institute. "We expect these discoveries to elucidate the proximal cause of fragile X syndrome as well as to provide new targets for drug therapy ," said principal investigator Stephen T. Warren, Ph.D., W. T. Timmie professor and chairman of the department of human genetics at Emory University School of Medicine and a Howard Hughes Medical Institute investigator.

Keyword: Genes & Behavior; Development of the Brain
Link ID: 992 - Posted: 11.15.2001

Postmenopausal women who take estrogen and young college-aged women perform more consistently on memory tests compared with postmenopausal women not taking the hormone, according to a new study by investigators at Columbia University College of Physicians & Surgeons. The researchers, led by Dr. Domonick Wegesin, assistant professor of neuropsychology (in neurology and in the Gertrude H. Sergievsky Center), say their findings have both clinical and research implications. Improvements in measures of consistency, they say, can be added to the list of the benefits of estrogen therapy, which already include decreased risk of Alzheimer's disease, osteoporosis and stroke. The results also may help neuroscientists localize areas in the brain where estrogen and aging may impact function. Since the ability to perform consistently has been associated with intact frontal lobe function, the findings suggest estrogen may mediate changes in cognitive abilities via the frontal lobe. Also, one's ability to perform consistently decreases with age. Therefore, changes in consistency with age may be related to age-related changes in frontal lobe function.

Keyword: Hormones & Behavior; Learning & Memory
Link ID: 991 - Posted: 11.15.2001