Looking at Picasso's cubist portrait "Girl with a Mandolin" , one critic might see a jumble of lines and angles, while another perceives a delicate young musician. Such is the difference between two brain areas involved in perceiving visual shapes. Now researchers suggest that one area--the one that sees a musician--can shut down the one that sees only lines. When light hits the retina, the visual signal zips to a region of the brain called the primary visual cortex, or V1. Neurons here respond to specific elements of an image--a vertical line, for instance--and send that information on to higher brain areas, including one called the lateral occipital complex (LOC). The LOC processes shapes, so that when we see four lines at right angles, we understand it to be a square. Now researchers say that when the LOC detects a pattern, it tells V1 to stop reporting on the component pieces. Copyright © 2002 by the American Association for the Advancement of Science.

Keyword: Vision
Link ID: 2901 - Posted: 06.24.2010

Scientists at Washington University School of Medicine in St. Louis have developed computerized atlases and associated tools for visualizing and analyzing two major components of the brain, the cerebral cortex and the cerebellar cortex. "It is vital to have improved methods for analyzing and visualizing the torrent of information that is becoming available from neurobiologists so that we can better understand the brain in health and disease," says David C. Van Essen, Ph.D., Edison Professor of neurobiology and head of the Department of Anatomy and Neurobiology. The cerebral cortex and the cerebellar cortex form the convoluted surfaces of the brain. The cerebral cortex is the seat of thought, learning, emotion, perception, sensation and movement. The cerebellar cortex also is important for movement and in coordinating the flow of information related to many functions, including cognitive processes as well as movement. . Copyright ©2002 Washington University in St. Louis.

Keyword: Cerebral Cortex
Link ID: 2900 - Posted: 06.24.2010

Researchers at Washington University School of Medicine in St. Louis are transplanting jellyfish genes into mice to watch how neural connections change in the brains of entire living animals. The development represents the merging of several technologies and enable researchers to watch changes inside living animals during normal development and during disease progression in a relatively non-invasive way. "This work represents a new approach to studying the biology of whole, living animals," says Jeff W. Lichtman, M.D., Ph.D., professor of anatomy and neurobiology. "I believe these methods will transform not only neurobiology, but also immunology and studies of organs such as the kidney, liver, and lung." Lichtman presented the work at the 40th annual New Horizons in Science Briefing, sponsored by the Council for the Advancement of Science Writing, held Oct. 27-30 at Washington University in St. Louis. Copyright ©2002 Washington University in St. Louis.

Keyword: Development of the Brain
Link ID: 2899 - Posted: 06.24.2010

Scientists have discovered a chemical in tobacco that may be partly responsible for causing diabetes, cancer, Alzheimer's disease and accelerating the ageing process. The chemical - nornicotine - is naturally present in tobacco, and is also produced when nicotine is broken down in the body. A team from Scripps Research Institute in the US has discovered that it reacts with proteins in the body, damaging their ability to perform their proper function. The process is the chemical equivalent of cooking and is the same reaction that browns seared sugars and caused food to age and spoil. The researchers have also discovered that nornicotine can have a second damaging effect - it reacts with commonly prescribed steroids, like cortisone and prednisone, potentially making them unsafe to use. (C) BBC

Keyword: Drug Abuse
Link ID: 2898 - Posted: 10.29.2002

By ERIC NAGOURNEY People hoping to stay sharp as they age often turn to crossword puzzles, math problems and other demanding intellectual pursuits. But is all that really necessary? A new set of studies suggests that it may be just part of the solution. Simply talking to people, the researchers say, appears to keep mental skills sharp. Copyright The New York Times Company

Keyword: Alzheimers; Intelligence
Link ID: 2897 - Posted: 10.29.2002

By DINITIA SMITH What maketh the man? Is it chromosomes? Or is it genitalia? Or, to borrow from Polonius, is it clothes? In her new book, "How Sex Changed: A History of Transsexuality in the United States," Dr. Joanne Meyerowitz, a professor of history at Indiana University and the editor of The Journal of American History, examines changing definitions of gender through the prism of transsexuality, that most mysterious of conditions in which a person is born with normal chromosomes and hormones for one sex but is convinced that he or she is a member of the other. Dr. Meyerowitz shows how mutable the words "male," "female," "sex" and "gender" have become, and how their meanings have evolved through time. Copyright The New York Times Company

Keyword: Sexual Behavior
Link ID: 2896 - Posted: 10.29.2002

By JAMES GORMAN In the dense conifer forests of northern Sweden, just below the Arctic Circle, the Siberian jay, its feathers the color of pine bark, hides its nests high in the tall pines and spruces. In the Southeastern United States, in fire-scoured piny woods, endangered red-cockaded woodpeckers take years to excavate very visible nest cavities. The cryptic jay is tracked with radio transmitters, the woodpecker simply by staking out its nest. But researchers say that the two birds have something in common. Given the choice, the young of each species often postpone independent life and all that comes with it — breeding, nests, the avian equivalent of mortgage payments — to hang around an extra year or longer with mom and dad. And they do not necessarily do it to be helpful. Copyright The New York Times Company

Keyword: Sexual Behavior
Link ID: 2895 - Posted: 06.24.2010

PITTSBURGH, A high school athlete with a history of three or more concussions who sustains a new concussion may be up to nine times more likely to experience common symptoms compared to high school athletes with no history of concussion, according to a University of Pittsburgh study, published in the November issue of the journal Neurosurgery. "The study is the first to actually demonstrate what have been the commonly assumed cumulative effects of multiple concussions in high school athletes," according to lead author Michael W. (Micky) Collins, Ph.D., a neuropsychologist and assistant director of the University of Pittsburgh Center for Sports Medicine's Concussion Program. "The study indicates for the first time in the high school athlete population that prior concussions may indeed lower the threshold for subsequent concussion injury and increase symptom severity in even seemingly mild subsequent concussions," he said. For more information about Dr. Collins, go to: http://www.upmc.edu/NewsBureau/sportsmed/collins_bio.htm. "Our findings are significant because high school athletes in contact sports are at high risk for repeated concussions, yet it is a population that has been understudied regarding concussion management," Dr. Collins said.

Keyword: Brain Injury/Concussion
Link ID: 2894 - Posted: 10.29.2002

By Sue Vorenberg Tribune Reporter If Los Alamos National Laboratory has its way, squids will soon be common in hospitals, universities and psychology wards. No, not those squids. SQUIDs: superconducting quantum interference devices. The name is complex but the function is simple: The devices measure tiny magnetic fields in the human body, which are about a billionth the size of the one around the earth that prompts compasses to point north. © The Albuquerque Tribune.

Keyword: Brain imaging
Link ID: 2893 - Posted: 06.24.2010

Physicians at UC Davis Medical Center have identified a promising new treatment for epilepsy that reduces the number of seizures while helping patients lead more productive lives. The study is the first to show that Levetiracetam (LEV), an antiepileptic drug typically used in combination with other drugs, might be successful as a single drug. The results were published in the October issue of Epilepsy and Behavior and will be presented at the American Epilepsy Association conference in Seattle this December. “We found that LEV can be effective as a single drug, or monotherapy, in patients with newly diagnosed epilepsy, as well as in patients with difficult-to-control seizures,” said Taoufik M. Alsaadi, assistant professor of neurology and co-director of the UC Davis Comprehensive Epilepsy Program. “In addition, it is very well tolerated, with only a small number of patients discontinuing the drug due to side effects.”

Keyword: Epilepsy
Link ID: 2892 - Posted: 06.24.2010

By Lauran Neergaard | The Associated Press WASHINGTON -- A toddler tumbles down stairs, a preschooler falls off a tricycle or a teen gets clobbered in football, and it's likely the emergency room will order a CT scan. But the majority of children with minor head injuries turn out to be fine, meaning too many kids are needlessly exposed to the scans' radiation, say specialists developing new guidelines that aim to cut by a third unnecessary CT scans of children's brains. CT scans -- computer-enhanced X-rays that can provide a better view of all parts of the body, not just the brain -- have revolutionized medicine. But the scans, more popularly known as CAT scans, emit significantly more radiation than a standard X-ray, and children are more sensitive to radiation than adults. Copyright © 2002, Orlando Sentinel

Keyword: Development of the Brain; Brain imaging
Link ID: 2891 - Posted: 06.24.2010

Some people may suffer from mysterious back pain because their brains are ultra-sensitive and wired up in a different way, say researchers. They have found that some people with lower back problems that appear to have no obvious physical cause seem to register pain much more easily than most people. A gentle squeeze so soft that it was not registered by healthy people was enough to trigger pain signals in their brains. A similar effect was also seen in patients with fibromyalgia, who suffer pain in the muscles, ligaments and tendons. But healthy people had to be squeezed a lot more sharply to feel the same level of pain - and it registered in different areas of the brain. The researchers, from the University of Michigan, say they do not know why this effect happens, but hope their work will help explain lower back pain. (C) BBC

Keyword: Pain & Touch
Link ID: 2890 - Posted: 10.28.2002

Scientists have found that men are more likely than women to be telling the truth if they say: "Not tonight darling, I've got a headache". A team of German researchers has begun to investigate the phenomenon of sexual headaches - a condition known as Orgasmic Cephalgia. They have discovered that it is three times more likely to strike men. The headaches usually come on suddenly around the point of orgasm, and can be very severe. The researchers believe the condition affects around one in a 100 people at least once during a lifetime, but some people are afflicted on a regular basis. Although the precise causes are not yet understood, it is thought that the condition may be linked to the increased blood flow and dilation of blood vessels that occur during sex. (C) BBC

Keyword: Sexual Behavior; Pain & Touch
Link ID: 2889 - Posted: 10.28.2002

Biochemical evidence may be the 'smoking gun,' but not all are convinced By Douglas Steinberg Many neuroscientists think that the master criminal behind Alzheimer disease is AB-secretase-42, the 42-amino-acid peptide that forms amyloid plaques in the brain. Two accomplices, the enzymes B-secretase-secretase and g-secretase, consecutively cleave AB-secretase from the much larger B-secretase-amyloid precursor protein (APP). What baffles investigators about g-secretase is that its substrate is a stretch of amino acids within APP's seemingly inaccessible transmembrane domain. Many genetic and cellular studies suggest that g-secretase's active site resides in the transmembrane protein presenilin-1 (PS1), which was first reported in 1995.1 Then in 2000, Merck & Co. labs in the United States and Great Britain provided compelling biochemical evidence in a Hot Paper2 favoring that hypothesis. Nevertheless, even Yue-Ming Li, who worked on this project and now heads the biochemistry and molecular pharmacology laboratory at Memorial Sloan-Kettering Cancer Center, acknowledges the need for much more data. "We don't have the final proof yet that PS1 is really the g-secretase." Indeed, some scientists argue that PS1 cannot be g-secretase. ©2002, The Scientist Inc.

Keyword: Alzheimers; Genes & Behavior
Link ID: 2888 - Posted: 06.24.2010

Many nerve terminals disappear in the a-synuclein mouse By Douglas Steinberg In the half-decade after human a- synuclein (ha-syn) was discovered in amyloid plaques purified from brains of patients with Alzheimer,1 neuroscientists logically suspected that this synaptic protein played a role in Alzheimer disease. Codiscoverer Eliezer Masliah began to develop an ha-syn transgenic mouse in 1996 that he hoped would serve as an Alzheimer model. Over the next two years, however, views about ha -syn underwent a radical makeover. Studies linked mutations in its gene to Parkinson disease and identified the protein in aggregates, known as Lewy bodies, which form inside neurons in Parkinson and other neurodegenerative disorders; ha-syn's role in Alzheimer disease appeared, in comparison, less compelling. Researchers began to envision an ha-syn mouse as the first transgenic Parkinson model. Masliah, a professor of neurosciences and pathology at the University of California, San Diego, published what he claims was the first report of an ha-syn mouse in this Hot Paper.2 The achievement was hard-won, he recalls, because a transgene can have unpredictable effects, depending on which promoter and which stretches of the gene are used. "We had to try a lot of different combinations until we came up with something that worked," he says. ©2002, The Scientist Inc.

Keyword: Parkinsons; Genes & Behavior
Link ID: 2887 - Posted: 06.24.2010

In the amygdala, fMRI shows greater neuronal activity in those with a short allele of the serotonin transporter promoter | By Harvey Black A team of scientists at the National Institute of Mental Health has found that a variant of the gene responsible for transporting the neurotransmitter serotonin is linked to greater activity of the amygdala within the brain.1 The researchers, led by Daniel Weinberger , chief of NIMH's Clinical Brain Disorders Branch, used functional magnetic resonance imaging in patients with one or two copies of the short allele of the serotonin transporter promoter. The fMRI demonstrated in-creased neuronal activity while these patients viewed faces showing emotional expressions. The findings show that the gene SLC6A4 affects cognition and emotionality and can be studied directly at the level of brain, says Weinberger. "This will ultimately inform us about why certain genes contribute to emotionality." The research involved 28 subjects: 14 had two copies of the long allele; the remainder had at least one copy of the short allele. MELDING TECHNOLOGIES "What's really interesting about this research is that it's the first time a certain gene [SLC6A4] has been tied to a clear-cut brain response that we can measure," says psychiatry professor Ned Kalin , University of Wisconsin-Madison. "It really melds two exciting technologies--fMRI and genomics--and puts them together in a creative way." Klaus-Peter Lesch , vice chair and professor in the Department of Psychiatry and Psychotherapy, University of Würzburg, commented in an E-mail, "The paper is an outstanding piece of work into the influence of gene variation on emotion processing and behavior." ©2002, The Scientist Inc.

Keyword: Emotions; Brain imaging
Link ID: 2886 - Posted: 06.24.2010

Developing safe, specific, powerful memory-improving drugs raises many ethical issues about the implications of cognitive enhancement | By Eugene Russo Though not suffering from any particular ailment, a 70-year-old woman becomes frustrated with the forgetfulness that often accompanies old age. She consults her doctor, who prescribes a memory enhancer. Within weeks, she can find her car keys and phone her children without using the speed-dial. Overwhelmed with reading assignments, a college freshman contacts his physician. The doctor prescribes a cognition enhancer: The student aces his exams. A soldier fights next to his buddy in a foxhole. While exchanging fire with the enemy, a bullet rips through his compatriot's skull, killing him instantly. Witnessing this, the surviving soldier goes into shock, despite the continuing firefight. Quickly, he reaches for a pouch, takes out a pill, and swallows it. Seconds later, he forgets what he saw and resumes shooting--and makes it out alive. ©2002, The Scientist Inc.

Keyword: Learning & Memory; Drug Abuse
Link ID: 2885 - Posted: 06.24.2010

Federal and biotech labs research a new generation of drug therapy that improves memory and concentration without side effects | By Eugene Russo Cognition--memory, perception, and attention--is a prerequisite to success, an essential for a normal life. When it becomes impaired through illness or accident, a person's life is turned upside down. Existing memory enhancement drugs treat maladies that rob memory, but they are relatively ineffective and have significant side effects. Some researchers, realizing the huge market that an aging, memory-slipping population can generate, are working to modify some drugs currently on the market and to generate others that improve memory, sharpen perception, and focus attention. Goals include increasing hippocampal levels of cycle AMP, and targeting ion channels and intracellular cascades. These hopeful cognition improvers are not household names. "The major pharmaceutical companies have been a little reluctant to venture into this arena," says Steven H. Ferris, executive director of New York University's Silberstein Aging and Dementia Research Center. "The small startup companies have nothing to lose. And frankly, whoever breaks through is going to be very successful. You can imagine what the market size is." THE SCIENCE OF COGNITIVE ENHANCEMENT For now, memory enhancement research is primarily geared toward neurodegenerative diseases. The few currently approved drugs are acetylcholinesterase inhibitors. Based on research in the 1960s and 1970s, these drugs work by boosting the effectiveness of the neurotransmitter acetylcholine. Oftentimes patients with Alzheimer disease have inadequate amounts of acetylcholine in the synapses between neurons. Acetylcholinesterase inhibitors increase the effectiveness of the neurotransmitters by inhibiting the enzyme that breaks down acetylcholine. Generally, however, these drugs have only modest effects in patients with Alzheimer disease. "The cholinergic approach is not sustained and not dramatic," says Rene A. Etcheberrigaray , laboratory director for NeuroLogic, in Rockville, Md. "The reason is very simple: It's not linked to an early pathophysiological event." ©2002, The Scientist Inc.

Keyword: Learning & Memory
Link ID: 2884 - Posted: 06.24.2010

By Arthur L. Caplan No area of science is command-ing more ethical attention these days than genetics. No other area of science with potential application to plants, animals, and people can match the speed with which new knowledge is being created in genetics. But lurking over in the disciplinary corner--somewhat out of sight of the ethicists' gaze--are the neurosciences. Advances in radiology, psychiatry, neurology, neurosurgery, bioengineering, and psychology are furthering our understanding of animal and human brains almost as quickly as genomics is fueling genetics. The brain revolution promises to be very controversial ethically. Already, some lawyers are trying to submit brain scans as evidence of their clients' lack of responsibility for crimes; government agencies are thinking about scanning the heads of prospective military pilots, astronauts, and secret agents to see who might be predisposed to what; doctors are implanting devices directly into the brain to help patients cope with parkinsonism or epilepsy; and many high-school kids who have no obvious learning disabilities are swallowing Ritalin and other drugs along with their coffee and tea to try to get an edge when they take their exams or scholastic aptitude tests. I think we're a little puritanical about the idea of mucking with our heads. Americans in particular have the belief that you should earn what you get, and that if you take a pill or use a surgical scalpel or drop in an implant, somehow you've cheated. But is it really wrong if altering the brain makes it possible to perform better, achieve more, or have greater capacities than one's parents? Here are some of the arguments I've heard that say it is wrong. I am not sure any of them are all that persuasive. ©2002, The Scientist Inc.

Keyword: Miscellaneous
Link ID: 2881 - Posted: 06.24.2010

Government, institutional, and pharmaceutical groups get together | By Ricki Lewis When actor Charlton Heston announced in August that he is "suffering symptoms consistent with Alzheimer's disease," he used qualified language because diagnosis is possible only postmortem. The lack of a clear set of symptoms and biomarkers is not only frustrating for families, but is hindering the search for treatments. "Guidelines for treating Alzheimer's focus on symptom relief, and these are not sufficient to develop drugs to delay or prevent symptoms," said Neil Buckholtz, head of the Dementias of Aging branch of the National Institute on Aging (NIA) at "Imaging Alzheimer's and other Neurodegenerative Diseases," a symposium held recently at the General Electric Global Research Center in Schenectady, NY. Investigators lack measures with which to monitor the efficacy of drug candidates. "The holy grail is to develop direct in vivo measurements of the plaque and tangle burden in the brain. But until a valid biomarker is available, better indirect measures of Alzheimer progression are needed," said Clifford Jack, director of the Alzheimer's Disease Research Center at the Mayo Clinic. Those biomarkers may be coming, thanks to the NIA's Alzheimer's Disease Neuroimaging Initiative, slated to begin by 2004 with $10 million-plus (US) from the National Institutes of Health, the Food and Drug Administration, the pharmaceutical industry, academic centers, device manufacturers, the Alzheimer's Association, and the Institute for the Study of Aging. Meetings between NIA and pharmaceutical companies led to the program. "The conclusion was that very little imaging has been done in clinical trials, and in most studies, the imaging quality wasn't very good," related Buckholtz. ©2002, The Scientist Inc.

Keyword: Alzheimers; Brain imaging
Link ID: 2880 - Posted: 06.24.2010