Researchers have uncovered a new culprit behind the brain injury suffered by stroke victims. Their new study, published in the Sept. 17 issue of Cell, links brain cell damage to a rise in brain acidity following the oxygen depletion, or ischemia, characteristic of stroke. The results may lead to new therapies designed to avert the often debilitating effects of stroke, for which successful treatments are currently lacking, the researchers said. A series of experiments in laboratory dishes and in animals implicates a recently described class of membrane ion channels, called acid-sensing ion channels (ASICs), to the influx of calcium in nerve cells starved of oxygen and subjected to acidic conditions. That calcium overload, long attributed to another group of cellular components, is essential for stroke injury as it sets off a cascade of events toxic to cells, said neurophysiologist and lead author of the study (Zhi-Gang Xiong of Robert S. Dow Neurobiology Laboratories in Portland, Oregon). What's more, the team reports, rats injected with agents known to block ASICs--including the venom of a tarantula spider--exhibited a reduction in brain damage from ischemia. Mice lacking a functional copy of the ASIC gene were similarly resistant to stroke damage, they found. "Our study offers multiple lines of evidence that reveal acid-sensing ion channels as major players in the damage suffered by stroke victims," Xiong said. "Furthermore, we found that existing pharmacologic agents that block those channels can dramatically reduce the amount of brain injury."

Keyword: Stroke
Link ID: 6125 - Posted: 09.17.2004

The origin of language stemmed from relationships, not genes By Ruth Walker Here is a book that gives new meaning to the old saying, "The hand that rocks the cradle rules the world." Its authors, one a psychiatrist and the other a psychologist and philosopher, have teamed up to tackle the momentous question of how humans developed language. Fearing not to challenge some of the heavyweights of modern science, from Jean Piaget to Noam Chomsky and Steven Pinker, they present their own theory: The development of language is connected primarily with affect rather than cognition, with the emotional learning that occurs in infants in the arms of those who love them. That is, language is rooted not in genes, not in the wiring of brains, but in behaviors we have learned over millenniums. Phrases like "emotional intelligence" and "the feeling brain" sound less oxymoronic today than they did before they appeared in the titles of groundbreaking works by Daniel Goleman and, more recently, Antonio Damasio. But in "The First Idea," Stanley Greenspan and Stuart Shanker contend that "emotional intelligence," as it is coming to be understood, is only one of the "roots and branches" of intelligence itself. "The trunk," they argue, is a set of abilities they refer to as the "functional-emotional developmental capacities." The critical concept in "The First Idea" is what the authors call "co-regulated emotional signaling." By this they mean the affectionate back-and-forth between baby and caregiver. Mom and Baby make eye contact, and when Mom smiles at Baby, Baby smiles back. Copyright © 2004 The Christian Science Monitor.

Keyword: Language; Development of the Brain
Link ID: 6124 - Posted: 06.24.2010

With cars blurring past to her left and right, Judy Niosi pried her fingers around the steering wheel as she drove along a major highway, struggling to come to grips with what she thought was a heart attack. "I was feeling was that my heart started pounding—forcefully—to the point where I thought my chest was going to explode," recalls the 37-year-old graphic artist. "My hands became sweaty and I had the constant thoughts that I was going to die." Niosi gulped down air, talked to herself in a soothing tone and somehow rumbled up her driveway a short while later. By then, her symptoms had disappeared. "I immediately got on the Internet looking for things, you know, heart attack symptoms to make sure that I wasn't having a heart attack," she says. "And I came across panic attacks and then I realized it must've been a panic attack." Her physician confirmed her suspicions. Doctors have long suspected that panic attacks like Niosi's—characterized by repeated bouts of intense fear that seem to come out of nowhere—could be hereditary and may result from the way our brains are wired. Piling up is new evidence that this may be the case. Psychiatrist Alexander Neumeister, an assistant professor at Yale University, reported in the Journal of Neuroscience that key brain receptors that receive chemical signals from other cells are deficient in those who suffer from panic attacks. The receptors help move the brain chemical serotonin—it regulates emotion—around the brain. © ScienCentral, 2000- 2004.

Keyword: Emotions
Link ID: 6123 - Posted: 06.24.2010

Helen Pearson A group of deaf Nicaraguan children who have created their own way of signing are giving linguists a precious glimpse of a language in its infancy. The kids are revealing how our brains are wired for learning language. It has long been debated to what extent our brains are a 'blank slate', able to learn any structure of language to which we are exposed, or whether they are hard-wired with grammatical rules. Existing languages do share fundamental rules. But this may simply be because different languages have influenced each other as they evolved. Linguists have attempted to answer the question by examining languages as they arise. For example, when people who speak different languages are pulled together, as they were by immigration or slavery, they rapidly evolve a pidgin language that can be polished over the years into a more sophisticated creole. But in these cases the communications are based on pre-existing languages. The Nicaraguan children are special because they have created a language from scratch. Deaf kids in the country lived in effective isolation until they were brought together in specialist schools in the late 1970s and 80s. Once the deaf children started to mingle, they began to communicate in their free time using gestures. They tend to stick with the signs they have acquired by the time they reach adolescence, so oldest set of children uses a relatively crude set of gestures. But younger generations have continued to refine them, forming a completely new language with its own grammatical rules. ©2004 Nature Publishing Group

Keyword: Language
Link ID: 6122 - Posted: 06.24.2010

Helen Pearson An injection of stem cells saved the sight of mice who would otherwise have gone blind, researchers reported this week. The study raises the prospect that some forms of human blindness might be treated with cells from a patient's own bone marrow. The research team focused on a group of eye diseases called retinitis pigmentosa, in which cells in the retina break down over time, causing gradual loss of vision and sometimes blindness. There is currently no good treatment for the condition, which affects around one in 3,500 people. Martin Friedlander at the Scripps Research Institute in La Jolla, California, and his team extracted a pool of stem cells from the bone marrow of adult mice and injected them into the eyes of newborn mice with a version of retinitis pigmentosa, before their retinas had begun to break down. The injections appeared to halt some of the eye's deterioration, the team found, particularly that of the cones, which are responsible for colour and fine vision. The treated mice were also able to detect light shone into their eyes, whereas a group that did not receive treatment went completely blind. "It's amazing," says Friedlander, who reports the results in the Journal of Clinical Investigation1. ©2004 Nature Publishing Group

Keyword: Vision; Stem Cells
Link ID: 6121 - Posted: 06.24.2010

Harvard scientist Margaret S. Livingstone first noticed it while standing in a gallery in the Louvre two years ago: In Rembrandt's self-portraits, his eyes seemed to be misaligned. Back at Harvard Medical School, Livingstone and a colleague looked at more of his many self-portraits and found others with his left eye looking outward, which probably indicated a disorder called amblyopia or lazy eye. Consequently, Rembrandt probably had little depth perception, which might have actually been an asset, since artists have to depict a three-dimensional world on a flat canvas, Livingstone said. Livingstone and another Harvard neurobiologist, Bevil R. Conway, who is also an artist, wrote about their observations in today's issue of the New England Journal of Medicine. "My hunch is because Rembrandt had one eye that consistently deviated, that he probably did have poor vision in that eye. But you can't tell that without testing," she said. Copyright © 2004, Newsday, Inc.

Keyword: Vision; Development of the Brain
Link ID: 6120 - Posted: 06.24.2010

Scientists have harnessed the body's own natural defences against infection to make a treatment for dementia. A German team, from Friedrich-Wilhelms University in Bonn, used proteins or antibodies produced by people against disease. Five Alzheimer's disease patients treated with the experimental vaccine therapy showed improvement in tests. More work is needed but the results are promising, said the authors in the Journal of Neurology, Neurosurgery and Psychiatry. People with Alzheimer's disease have 'amyloid' deposits in the brain that are made up of a protein beta peptide. These deposits get progressively worse and damage the brain tissue, leading to dementia. Scientists have been looking at ways of blocking the action of beta peptide to prevent the build up of amyloid deposits using vaccines. Now Dr Richard Dodel and colleagues believe they have found a way to do this, using the body's own natural defence system, in humans. When the body encounters a disease or infection it produces complex protein molecules called antibodies to seek out and destroy the invasion. (C)BBC

Keyword: Alzheimers
Link ID: 6119 - Posted: 09.16.2004

Regardless of the language they are learning to speak, young children learn vocabulary in fundamentally the same way, according to a study by researchers at the National Institute of Child Health and Human Development of the National Institutes of Health. The researchers found that, for the seven languages studied, nouns comprise the greatest proportion of 20-month-old children’s vocabularies, followed by verbs and then adjectives. The findings appear in the July-August issue of Child Development. “This study shows that while languages may differ greatly, the sequence by which young children learn the parts of speech appears to be the same across different languages,” said Duane Alexander, M.D., Director of the NICHD. “By learning about the normal progression of language development, we may be able obtain information that will help children who are having difficulty learning language.” For the study, Marc Bornstein and Linda Cote, researchers in NICHD’s Child and Family Research Laboratory collaborated with researchers in Argentina, Belgium, France, Israel, Italy and the Republic of Korea to study language development in children learning to speak Spanish, Dutch, French, Hebrew, Italian, Korean, and American English. “Specifically, mothers in every country reported that their children said significantly more nouns than any other word class (verbs, adjectives, closed-class words),” the researchers wrote.

Keyword: Language
Link ID: 6118 - Posted: 06.24.2010

Close your eyes and acutely listen to the sounds around you, and you'll find you're able not only to accurately place the location of sounds in space, but their motion. Imagine then that, strangely, you suddenly became unable to distinguish the motion of sounds, even while you retained the ability to pinpoint their location. That's exactly the experience of a patient reported by Christine Ducommun and her colleagues, who used studies of the patient to demonstrate conclusively for the first time that the brain has a specialized region for processing sound motion. While it was known that the visual system has a specialized region for perceiving motion, it wasn't known whether the auditory system has such a region--or whether sound location and motion are processed by the same circuitry. Previous studies of the capabilities of brain-damaged patients had found only that both their location and motion processing abilities were impaired, and animal and human neuroimaging studies had not been able to conclusively tease apart the two abilities. Ducommun and her colleagues discovered the region by studying a woman who was to be operated on to alleviate intractable temporal lobe epilepsy. The operation would involve the removal of the affected regions of the right anterior temporal lobe and the right posterior superior temporal gyrus (STG).

Keyword: Hearing
Link ID: 6117 - Posted: 09.16.2004

STANFORD, Calif. - From the munchies to the giggles to paranoia, smoking marijuana causes widespread changes in the brain. Now researchers at Stanford University School of Medicine are a step closer to understanding how the drug's active ingredients - tetrahydrocannabinol and related compounds, called cannabinoids - may exert their effects. David Prince, MD, the Edward F. and Irene Thiele Pimley Professor of Neurology and Neurological Sciences, and his colleagues found that a group of neurons that act as information gatekeepers in the brain's major information processing center, called the cerebral cortex, release cannabinoids that quiet their own activity. This form of self-inhibition is a novel way for neurons to regulate their own ability to send messages to their neighbors. Tetrahydrocannabinol from marijuana may work its brain-altering magic by binding to these same cells. "Marijuana is a major drug of abuse with actions in the brain that aren't entirely known. Now we understand one piece of the puzzle," Prince said. The work of Prince and his colleagues John R. Huguenard, PhD, associate professor of neurology and neurological sciences, and Alberto Bacci, PhD, staff research associate, is published in the Sept. 16 issue of Nature.

Keyword: Drug Abuse
Link ID: 6116 - Posted: 09.16.2004

The first clinical trial of a therapy based on the much-heralded technique of RNA interference, or RNAi, will begin within several weeks to treat a condition which can lead to blindness. The technique works by silencing a key gene involved in a progressive disorder of the retina called wet age-related macular degeneration (AMD), say executives at Acuity Pharmaceuticals, a private biotechnology company in Philadelphia, US. RNAi is a naturally occurring process in which the presence of double-stranded RNA (dsRNA) in cells triggers a series of steps that ultimately destroys messenger RNA (mRNA) and shuts down protein production. It is believed to have evolved to protect cells from invading viruses. In the upcoming Phase I trial, doctors will inject many copies of Cand5, a “small, interfering” double-stranded RNA, or siRNA, directly into the eyeballs of patients suffering from the disabling eye disorder. “It’s tremendously exciting,” says Michael McManus, an RNAi expert at the University of California San Francisco, US. “It represents the first step in using this technology to treat a human disease.” © Copyright Reed Business Information Ltd.

Keyword: Vision
Link ID: 6115 - Posted: 06.24.2010

Erika Check Advisers to the US Food and Drug Administration (FDA) have told the agency to issue a sweeping new warning about the risks of all antidepressants in children. The warning would state that such medicines cause some children to try to commit suicide. This is a step up from warning labels adopted by the FDA in March, which say that antidepressant drugs are associated with a risk of suicide in children, but do not necessarily cause it. The warning would appear on all antidepressants on the market, as well as those approved in the future. The committee said antidepressants should also be sold with a guide that tells parents to monitor children on the drugs for suicidal tendencies. The advisers came to their conclusions last night after a two-day hearing, in which they examined data from 24 clinical trials, as well as hearing passionate testimony from patients, parents and doctors who work with depressed children. The FDA convened the hearing on 13 September to ask its advisory committee how to interpret the clinical trials, which examined the effect in children and teenagers of nine antidepressant medications on five types of mental illness. The FDA usually adopts its advisory committee's recommendations, but will discuss them internally before announcing a decision, says Robert Temple director of the Office of Drug Safety in the agency's drug evaluation centre. ©2004 Nature Publishing Group

Keyword: Depression; Development of the Brain
Link ID: 6114 - Posted: 06.24.2010

By LAURAN NEERGAARD WASHINGTON -- All drugs used to treat depressed children should carry a "black box" warning of the antidepressants' link to increased suicidal thoughts and actions, says a panel of federal advisers. The warning, among the strongest in the Food and Drug Administration's arsenal, should reach doctors no matter how they get drug information and would extend to drug advertising directed at patients. That's the majority opinion of federal advisers, who heard testimony Monday about antidepressants' powers and perils from doctors, researchers and relatives of patients who killed themselves after taking such medication. The panel spent the bulk of Tuesday deliberating before issuing its recommendation. The black box option is more strident than the bold-letter warnings the same federal advisers suggested be added to antidepressant labels this March. Antidepressant prescription rates to children were unchanged by the earlier warning. Unlike the earlier red flag, advisers said this new warning should make clear that antidepressants have been linked to two to three more children per 100 having heightened suicidal thoughts and behaviors. Copyright © 2004, The Associated Press

Keyword: Depression; Development of the Brain
Link ID: 6113 - Posted: 06.24.2010

By BENEDICT CAREY Watching the summer's events unfold - war protests, an Olympics scoring scandal, numerous terror scares - some people may have felt that it was all very familiar, that they had somehow been through this before. Yet psychologists say it is usually life's more mundane details - the click of a radiator, the play of the shadows on a tablecloth - that prompt that sudden and sometimes breathtaking sense of familiarity. "The way the coffee cups were lined up on the table," said Gretchen Purcell, 24, a business consultant in the Washington area who felt this so strongly during a conference-call meeting last month that it made her laugh out loud. "The whole scene was so familiar I thought I knew what people were going to say before they said it. It was like I was in a movie I'd already seen." French for just that ("already seen"), déjà vu is the sort of fleeting, intimate experience that reveals itself more readily to novelists than to researchers. As recently as the 1990's, social scientists doing population surveys asked about it in the same breath as they inquired about poltergeists and contact with the dead. But new research on memory has opened a promising window on the phenomenon, providing both possible explanations for the sensation and novel ways to create and measure it. Copyright 2004 The New York Times Company

Keyword: Miscellaneous
Link ID: 6112 - Posted: 09.15.2004

Children who take the anti-depressant Prozac are at greater risk of attempting suicide, say US experts. The drug is currently the only anti-depressant which doctors can prescribe to under-18s in the UK. Other similar drugs are considered too dangerous because previous studies have linked them to an increase in suicidal tendencies. However, an analysis by the US Food and Drug Administration has found that Prozac too may pose a risk. The analysis was overseen by Dr Robert Temple, director of the FDA office of drug evaluation, who gave evidence on Tuesday at a hearing to determine whether tougher warning labels were needed for anti-depressants. He said: "I think we now all believe there is an increase in suicidal thinking and action that is consistent across all the drugs." The FDA decided that all antidepressant drugs should carry the strongest possible warnings that they could cause children to harm themselves. In future, the drugs will have to black boxes spelling out the potential risks. On average, the analysis, carried out by experts at Columbia University, New York, found anti-depressants taken by children will cause an extra 2% to 3% to have increased suicidal thoughts. (C)BBC

Keyword: Depression; Development of the Brain
Link ID: 6111 - Posted: 09.15.2004

(Santa Barbara, CA) --Scientists at the University of California, Santa Barbara have made an important discovery that will increase the understanding of multiple sclerosis, a debilitating disease of the central nervous system in which the myelin sheath, an insulating membrane surrounding the nerve cells in the brain and spinal cord, start to unravel for reasons as yet unknown. In a paper appearing in today's issue (Sept. 14) of the Proceedings of the National Academy of Science, several UC Santa Barbara researchers describe the results of a study that shows why the unraveling occurs. The myelin sheath is made up of a lipid bilayer (similar to those making up the cell membrane) wrapped many times around the nerve axon -- the part of a nerve cell through which impulses travel away from the cell body. One specific protein, called myelin basic protein, acts to hold the myelin sheath together tightly around the axon. The axons serve as the electrical wires that connect the nerve cells, and the myelin serves as the insulation to keep the electrical impulses flowing quickly and reliably. "If the myelin breaks down, for whatever reason, the nerve electrical impulses leak out, slow down, and generally don't work very well," says Joe Zasadzinski, professor of chemical engineering at UCSB.

Keyword: Multiple Sclerosis
Link ID: 6110 - Posted: 09.15.2004

As a child, Beth Livermore, mother of two from Bedminster, New Jersey, just wanted to have fun on her bicycle. "When I was a child I borrowed my mom's bike," she recalls. "We set up jumps and I routinely went over the handlebars. Didn't think a lot about it—of course we didn't wear helmets." But as a parent she wants her kids to be safe. "With the kids we're really careful, they wear helmets, always." Helmets are a good idea because the brain can be easily injured and treatment options are very limited. Millions of Americans suffer serious non-penetrating head injuries every year, commonly from activities such as cycling, sports and car accidents, which can result in localized brain damage, memory loss and death. Brain researchers have long known what happens in the injured brain during the first hour after a head trauma. Initially there is a large outflow of glutamate, a chemical neurotransmitter by which nerve cells in the brain communicate with each other and other cells. When this excess of glutamate binds to certain receptors on the surface of other nerve cells, the receptors become so overactive, or excited, that the cells die. These receptors are an essential part of forming memories, which could explain the memory loss that commonly results from head trauma. © ScienCentral, 2000- 2004. All

Keyword: Brain Injury/Concussion
Link ID: 6109 - Posted: 06.24.2010

By Anna Salleh, ABC Science Online — There may be more left-handed people than we realize, an international study has found. If we include the number of people who throw a ball, strike a match or use a pair of scissors with their left hand, the researchers say the world looks more of a left-handed place. Australian researcher Sarah Medland of the Queensland Institute of Medical Research in Brisbane and team publish the research in the current issue of the journal Laterality. Left-handed people face problems in a world where most things, from scissors to can-openers and computers to power tools, are designed for right-handers. In the past left-handers faced even greater problems. Some schoolchildren were forced, under threat of the strap, to write with their right hand, regardless of their natural tendency. Medland and team hoped to shed light on the contribution of cultural factors like this on the distribution of handedness. Copyright © 2004 Discovery Communications Inc.

Keyword: Laterality
Link ID: 6108 - Posted: 06.24.2010

In a finding that may cause a dramatic shift in the way scientists and researchers search for a therapy for Alzheimer's disease, a team of researchers led by Jeff Johnson, an associate professor at the School of Pharmacy, has discovered that increased expression of a protein called transthyretin in the brain appears to halt the progression of the disease. The findings appear in the current issue of The Journal of Neuroscience. "This work shows convincingly that if we can intervene in Alzheimer's pathology by introducing molecules and drugs into the brain and increase transthyretin levels, we could slow the progression of the pathology," says Johnson, who co-authored the report with Thor Stein, a former graduate student in UW's M.D./Ph.D. program who performed most of the experiments. "Even if patients have plaque formation in the brain, they still could have normal function." For years, researchers have focused on creating an animal model that mimics the pathology of Alzheimer's disease to test potential therapies. By genetically engineering mice to express mutated genes from the families of patients with early-onset Alzheimer's disease, researchers produced several mouse lines that over-express the human amyloid precursor protein (APP), a protein involved in the disease development. While the mice developed plaque formation in their brains, they didn't develop the other hallmark of Alzheimer's disease -- neurofibrillary tangles, a leading indication that neural cells are dead or dying. Copyright © 2004 The Board of Regents of the University of Wisconsin System

Keyword: Alzheimers
Link ID: 6107 - Posted: 06.24.2010

Michael F. Dorman, Blake S. Wilson Ludwig van Beethoven was 28 years old when he first noticed a ringing and buzzing in his ears. Soon he was unable to hear high notes from the orchestra; speech became indistinct. By 1802, four years after the first symptoms, he was profoundly deaf. Beethoven fell into a deep depression. He describes this period in his Heiligenstadt Testament, meant to be read after his death: For me there can be no relaxation in human society; no refined conversations, no mutual confidences. I must live quite alone and may creep into society only as often as sheer necessity demands.... Such experiences almost made me despair, and I was on the point of putting an end to my life—the only thing that held me back was my art ... thus I have dragged on this miserable existence. In 2001, Scott N. was 34 and had lost all of his hearing. A surgeon inserted 16 tiny electrodes into his inner ear, or cochlea, and connected them to a small package of electronics implanted under the skin. A year later, Scott came to author Dorman's laboratory at Arizona State University to test his understanding of speech. The results were extraordinary: Scott recognized 100 percent of more than 1,400 words, either in sentences or alone, without any prior knowledge of the test items. © Sigma Xi, The Scientific Research Society

Keyword: Hearing; Robotics
Link ID: 6106 - Posted: 06.24.2010