Results Offer Hope for Some Paralyzed People to Control Robots and Computers By Shankar Vedantam Washington Post Staff Writer Electrodes implanted in a monkey's brain have enabled the animal to move a cursor on a computer screen just by thinking about it, researchers announced yesterday. It is the latest development in a new field of research called neuroprosthetics that could one day help some paralyzed people use their thoughts to control robots and computers. Other researchers have previously implanted electrodes in monkeys and people and shown that brain signals can move a cursor. The new work increases the speed and accuracy with which the brain can direct the cursor. Researchers believe they are perhaps a decade away from perfecting the technique for paralyzed patients. © 2002 The Washington Post Company

Keyword: Robotics
Link ID: 1703 - Posted: 06.24.2010

By Jennifer Fisher Wilson The discoverer of prions, the pathogens implicated in the fatal, brain-wasting mad cow disease (bovine spongiform encephalopathy, BSE) and Creutzfeldt-Jakob disease (CJD), announced recently that a therapy against them would likely be available within the next five to 10 years, but he added that scientists are still mystified by exactly what circumstances cause the pathogens to produce infections in animals and humans. "We thought that the number of cases of the disease would increase two to three times, but the number of cases in 2001 was similar to the number in 2000," Stanley B. Prusiner, 1997 Nobel Prize winner, told a crowded room of scientists at the University of Pennsylvania on Feb. 13. Prion diseases are difficult to predict, he said, because they involve so many variables. For example, it is still unknown why the new variant form of CJD disease, caused by BSE, is confined to young people while inherited CJD, also known as sporadic CJD, afflicts only the aged, he said. . C. Korth et al., "Acridine and phenothiazine derivatives as pharmacotherapeutics for prion disease," Proceedings of the National Academy of Sciences, 98:9836-41, 2001. The Scientist 16[6]:28, Mar. 18, 2002 © Copyright 2002, The Scientist, Inc. All rights reserved.

Keyword: Prions
Link ID: 1702 - Posted: 06.24.2010

* Alcohol consumption and cigarette smoking often go hand in hand. * A rodent study has found that low doses of alcohol and nicotine can have an additive effect on the release of the neurotransmitter dopamine. * A related study has found that a nicotine blocker called mecamylamine can reduce the rewarding effects of alcohol in humans. * The two studies collectively suggest that nicotinic mechanisms are involved in alcohol consumption. It’s no secret that smokers often drink, and drinkers often smoke. Addiction scientists believe that alcohol consumption may contribute to increased cigarette smoking; certainly alcohol is considered a major risk factor for relapse during smoking cessation. Similarly, smoking is believed to increase the pleasurable effects of alcohol, and may be a risk factor for alcoholism relapse. Two studies in the March issue of Alcoholism: Clinical & Experimental Research examine the mechanisms underlying the two addictive behaviors. One study uses rodents to investigate the impact that alcohol and nicotine have on dopamine (DA) release in the brain; the other study looks at the impact a drug used to block nicotinic effects called mecamylamine has on alcohol’s effects for humans. The results collectively suggest that nicotinic mechanisms are involved in alcohol consumption.

Keyword: Drug Abuse
Link ID: 1700 - Posted: 06.24.2010

Findings published in current edition of Journal of Neurophysiology -- Bethesda, MD -- The four million Americans who have been diagnosed with Alzheimer’s disease (AD) experience symptoms which include progressive mental deterioration, confusion, a loss of memory and an inability to calculate the simplest of numbers. This may be due to the fact that people with Alzheimer's have fewer brain cells and less of some important neurotransmitters than people without the disease. The Importance of Galanin Previous research has established that a substance called “galanin” is associated with learning and memory and is involved in brain function, and disorders such as epilepsy. When a nerve is cut or injured, the neuron produces extra galanin, possibly to repair or modulate the damage. The production of galanin may be one way that the body tries to repair nerve damage. Unfortunately, accepted literature states when the onset of AD occurs, galanin hyperinnervation (excessive supply) of nerve cells that employ acetylcholine as their neurotransmitter in the basal forebrain of AD patients occurs and depresses acetylcholine release and its inhibitory actions at other central nervous system sites. Copyright © 2002, The American Physiological Society

Keyword: Alzheimers
Link ID: 1699 - Posted: 06.24.2010

Binge-eating, a disorder that can lead to obesity in young women, can be predicted by looking at a girl's negative emotions, including dissatisfaction with her body image, new data confirms. Only certain negative emotions, however, were linked to an increased risk of binge eating. "Heightened depressive symptoms and emotional eating, as well as low self-esteem, but not anxiety symptoms and anger, predicted binge eating onset," says Eric Stice, Ph.D., an assistant professor at the University of Texas at Austin, writing in the current issue of Health Psychology. Similarly, not all types of social support were linked to binge eating. Low peer support increased a girl's risk, but low parental support did not have any effect. Teenagers' risk of binge eating was not related to their age, ethnicity or level of parental education.

Keyword: Anorexia & Bulimia; Emotions
Link ID: 1698 - Posted: 03.15.2002

John McKenzie [ABCNEWS.com] — For many Americans, losing the ability to think and remember is the single biggest fear about growing older. A new study published in the Archives of Neurology finds that women 65 and older who had high levels of cholesterol were more likely to have problems thinking clearly than those with healthy cholesterol levels. Researchers now suggest that some women may have difficulty thinking clearly because what they eat causes high cholesterol. Copyright © 2002 ABCNEWS Internet Ventures.

Keyword: Alzheimers; Learning & Memory
Link ID: 1697 - Posted: 06.24.2010

There has been a recent upsurge of interest in placebo effects (e.g., Blakeslee, 1998 a, b; Brown, 1998; Harrington, 1997; Holden, 2002; Moerman, 2001; Petrovic, Kalso, Petersson, and Ingvar, 2002). The word placebo (from the Latin, I shall please) has two related meanings: (1) a substance containing no medication but prescribed or given to reinforce a patient's expectation to get well; (2) an inactive substance or treatment used as a control in an experiment to test the effectiveness of a drug or medical treatment.

Keyword: Newsletter; Pain & Touch
Link ID: 1695 - Posted: 03.15.2002

The clue to understanding anxiety may be written in your genes By Jocelyn Selim When Charles Darwin returned to England in 1836 after his five-year voyage on the Beagle, he was 27 years old and on the cusp of one of the most brilliant careers in the history of science. He was also a bit of a wreck. He began complaining of "constant attacks"—heart palpitations, trembling, shortness of breath, and "swimming in the head." When offered a secretaryship at the Geological Society of London, he declined, explaining that "anything that flurries me completely knocks me up afterward." Two years later the once-intrepid traveler moved to his country home in Kent and became a legendary recluse, leaving only when absolutely necessary and then traveling in a carriage with darkened windows. On one rare trip in 1861, a brief speech in front of the Linnean Society prompted a 24-hour vomiting episode. Darwin never learned the true nature of his malady. Physicians of the time diagnosed it as anything from "dyspepsia with aggravated character" to "suppressed gout"; their successors might have attributed it to a weak nervous system or a conflicted superego. But according to a team of researchers led by Xavier Estivill, a molecular geneticist at Barcelona's Medical and Molecular Genetics Center, Darwin's agoraphobia may have had a more specific origin. In a study published in the journal Cell last summer, Estivill contended that nearly every social phobia and panic disorder is rooted in a single stretch of about 60 genes. Anxiety disorders first caught Estivill's attention 14 years ago through the work of physician Antoni Bulbena. While working at the Hospital del Mar in Barcelona, Bulbena made an odd observation: Patients who were double-jointed complained of nervous disorders far more often than others—fully 16 times as often, a follow-up study showed. Intrigued by the coincidence, Estivill traveled to a small Catalonian village near Barcelona, collected DNA samples from families known to have both conditions, and began combing through the samples for common characteristics. © Copyright 2002 The Walt Disney Company.

Keyword: Stress; Emotions
Link ID: 1692 - Posted: 06.24.2010

A quarter of obese children are already showing signs of changes that could lead to full-blown diabetes. The finding supports doctors' fears that many of today's "couch potato generation" could be falling prey to the disabling disease before they hit their 30s. It has been known for some time that being obese, or even overweight, can greatly increase the chances of diabetes, but evidence is growing that younger and younger patients are at risk. The study, by researchers at Yale University in the US, looked at more than 150 obese children, aged between four and 18. They found that in the 55 aged four to 10, 25% were showing signs of "insulin resistance". (C) BBC

Keyword: Obesity
Link ID: 1691 - Posted: 03.14.2002

Researchers have watched monkeys weigh different decisions while tracking the behavior of individual neurons in their brain. The work, reported in the 14 March issue of Neuron, shows how neurons keep track of recent events while making a comparison. In past experiments, neuroscientists had monitored the steps involved in making a decision: neurons encoding sensory information, comparing stimuli, and preparing commands to move muscles, among others. In this new study, Ranulfo Romo and colleagues at the National Autonomous University of Mexico in Mexico City observed the complete unfolding of a decision, including a crucial step--neurons' ability to keep a trace of recent events in memory while making a comparison. They focused on the activities of neurons in a brain region called the medial premotor cortex (MPC); this region is primarily involved in commanding body movements, but Romo and others suspect it participates in sensory processing and can retain memories. To test whether this means that the MPC helps make decisions, the researchers applied a vibration to monkeys' fingertips for half a second. After 1 to 3 seconds, they then applied a second vibration at a different frequency. The animals learned to press a button to indicate which frequency was higher. As the animals mulled over which button to push, the researchers used electrodes to track the firing of individual neurons in the MPC. --MARINA CHICUREL Copyright © 2002 by the American Association for the Advancement of Science.

Keyword: Robotics; Movement Disorders
Link ID: 1690 - Posted: 06.24.2010

Chewing gum may help to make people smarter by improving memory and brain performance, research suggests. In tests, scientists found the ability to recall remembered words improved by 35% among people who chewed gum. However, contrary to popular belief, they say it does not aid concentration. The scientists from the University of Northumbria, in Newcastle upon Tyne, cannot explain why memory is affected, but are working on two theories. One is that chewing raises the heart beat, which causes more oxygen and nutrients to be pumped into the brain. The other is that it triggers the production of insulin, which stimulates a part of the brain involved in memory. (C) BBC

Keyword: Learning & Memory
Link ID: 1689 - Posted: 03.14.2002

HELEN PEARSON Smokers who resolve to quit often feel the first painful pangs an hour after their last cigarette. Researchers have now identified the brain circuits that trigger this craving, which might offer new routes to beating addiction. One lungful of smoke swamps brain cells with nicotine, causing release of reward chemical dopamine. Within seconds, the same cells become desensitized to nicotine. So it is unclear why smokers enjoy a whole cigarette. Nicotine influences other brain circuits that fine-tune the dopamine release, Daniel McGehee and his team at the University of Chicago in Illinois have found. In particular, a hit of nicotine switches off one circuit for about an hour. This circuit normally stops cells releasing dopamine1. * Mansvelder, H.D., Keath, J.R. & McGehee, D.S. Synpatic mechanisms underlie nicotine-induced excitability of brain reward areas. Neuron, 33, 905 - 919, (2002). * Mansvelder, H.D. & McGehee, D.S. Long-term potentiation of excitatory inputs to brain reward areas by nicotine. Neuron, 27, 349 - 357, (2002). © Nature News Service / Macmillan Magazines Ltd 2002

Keyword: Drug Abuse
Link ID: 1688 - Posted: 06.24.2010

Embryonic motor systems intrinsic to central nervous systems and not dependent on sensory cues by Janet Wong - An animal's ability to move - like the kicking of a developing baby or the crawling and walking of insects - is intrinsic, not dependent on sensory stimulation, says a U of T neurobiologist. "All animals, from worms to humans, have rhythmic movements that underlie locomotion," says Max Suster, a post-doctoral fellow at U of T at Mississauga and lead author of a paper in the March 14 issue of Nature. "The question is whether this ability is built into the neurons of central nervous systems or whether sensory input from the outside world helps organize those movements so that they are suitable to real life. Our research suggests that the development of embryonic motor systems is largely intrinsic to central nervous systems and not dependent on sensory cues like touch or smell." Suster and University of Cambridge professor Michael Bate examined the development of rhythmical movements in a type of fruit fly known as Drosophila. They compared fly embryos that received sensory input to those deprived of stimulation through methods of genetic engineering.

Keyword: Development of the Brain
Link ID: 1687 - Posted: 03.14.2002

NEI study at Emory, elsewhere finds atropine drops work as well as standard treatment for amblyopia (ATLANTA) A National Eye Institute (NEI) study, conducted at more than 40 sites nationwide including Emory Eye Center, has found that atropine drops, given once a day to treat amblyopia or lazy eye -- the most common cause of visual impairment in children -- work as well as the standard treatment of patching one eye. This research finding in the Amblyopia Treatment Study may lead to better compliance with treatment and improved quality of life in children with this eye disorder. These results appear in the March issue of Archives of Ophthalmology. After six months of treatment, researchers found that the drug atropine, when placed in the unaffected eye once a day, can work as well as eye patching and may encourage better compliance. Compliance is an important factor in the success of amblyopia therapy. Treatment should be started when the child is young, since amblyopia is more effectively treated in children under seven years of age. Timely and successful treatment for amblyopia in childhood can prevent lifelong visual impairment.

Keyword: Vision; Development of the Brain
Link ID: 1685 - Posted: 03.14.2002

By Jeremy Laurance Health Editor The causes of autism, the fast-growing disorder that has struck fear into the middle classes and has been linked with the MMR vaccination, may be less mysterious than has been thought, scientists report today. The developmental disorder characterised by "extreme autistic loneliness" and "an obsessional desire for the maintenance of sameness" according to Leo Kanner, who first described it in 1943, has risen seven-fold in the UK in the last decade but no biological reason for the rise has been found. Now a new study has discovered that in up to a third of cases it may be possible to identify the cause of the condition. Researchers in the Netherlands who ran detailed tests on 25 adults with autism found definite or probable causes of the disorder in nine of them. © 2002 Independent Digital (UK) Ltd

Keyword: Autism
Link ID: 1683 - Posted: 06.24.2010

By Rhonda Rowland CNN Medical Unit ROCHESTER, Minnesota (CNN) -- Children have at least a 7 1/2 percent chance of being diagnosed with ADHD some time between age 5 and high-school graduation, according to a new Mayo Clinic study. ADHD, or attention deficit hyperactivity disorder is a brain disorder characterized by hyperactivity and inattention. ADHD is the medical term for what's widely referred to as ADD. "That's a large number of kids affected at some point during childhood," said Dr. William Barbaresi, developmental and behavioral pediatric specialist at the Mayo Clinic, who is lead author of the study published in Archives of Pediatrics and Adolescent Medicine. "ADHD is without question a very common condition that affects a large number of children and we have to deal with it in a systematic fashion in school and in the medical system. We can't ignore a problem that affects such a large number of kids." © 2002 Cable News Network LP, LLLP.

Keyword: ADHD
Link ID: 1682 - Posted: 06.24.2010

BY JIM WILSON We seriously doubt William Congreve would have said "music hath charms to soothe the savage breast" if his son's band had practiced in the basement. The point that Congreve so memorably made more than 300 years ago, however, still rings true. Music elicits unconscious reactions. Brahms reportedly puts cranky babies to sleep. Mozart supposedly helps kids score better on tests. Pleasant melodies of all sorts are said to lift depression, relieve anxiety and reduce pain associated with cancer. I've used a lot of weasel words here because psychiatrists are divided on whether the positive effects result from listening to music or the infamous placebo effect. But having expressed this reservation, they acknowledge that sounds can indeed provoke the nervous system. The most dramatic examples are two types of epileptic seizures. High-frequency sound waves can trigger "audiogenic seizures." The emotional reactions to music can cause "musicogenic seizures." Now there is one more thing die-hard scientific skeptics will have to accept about the effects of sounds: Practicing a musical instrument physically changes the structure of the brain.

Keyword: Hearing
Link ID: 1681 - Posted: 03.14.2002

By Paul Eng [ABCNEWS.com] March 13 — Tired of monkeying around with a mouse in order to work with your computer? The good news: One day, you may be able to control your PC just by thinking. Researchers have pursued such futuristic man-to-machine connections for years in the hopes they could allow paralyzed people to more easily control computers or other complex devices such as artificial limbs. And scientists at Brown University in Providence, R.I., say the results of their latest research, to be published in this week's Nature journal, may help bring such possibilities closer to reality. Copyright © 2002 ABCNEWS Internet Ventures.

Keyword: Robotics
Link ID: 1680 - Posted: 06.24.2010

Learning Associated With Increase in Transport Molecules in Brain HOUSTON, Can't remember where you put your keys, or how to retrieve your voicemail? Your brain's cleaning crew may be asleep on the job. Molecular "brooms" that whisk away excess amounts of the chemical glutamate in the brain may play a key role in learning and memory formation, suggest recent animal studies by scientists at the University of Houston. In the brain, several chemicals called neurotransmitters carry messages in the spaces connecting one nerve cell, or neuron, to the next, allowing the brain to function properly. Scientists believe that the strengthening of these connections by the neurotransmitter glutamate - a process called long-term potentiation - is one mechanism responsible for the storage of some memories. Now, for the first time, researchers at the University of Houston have determined that levels of transport molecules for glutamate - chemicals that latch on to and "sweep away" glutamate - increase during learning, suggesting that this molecular cleaning crew has an important role in the process.

Keyword: Learning & Memory
Link ID: 1678 - Posted: 03.13.2002

PITTSBURGH, – A multi-center, international collaborative team of researchers is the first to identify a region on chromosome 1 that may contain genes that make an individual vulnerable to developing anorexia nervosa (AN). The findings add to a growing body of research supporting the belief that genetic transmission – in addition to psychosocial factors – contributes to a person’s vulnerability to develop AN. The study, in the March issue of the American Journal of Human Genetics, is the first genome-wide linkage analysis of eating disorders and uses an affected relative pair research method that looks for genes that run in families where two or more people have a disorder. Results from a linkage study provide stronger evidence of a genetic basis for an illness than those from population-based association studies, where people with a disorder are compared with samples from the general population.

Keyword: Anorexia & Bulimia; Genes & Behavior
Link ID: 1677 - Posted: 06.24.2010