 |
 |
PRESS RELEASE: BW5492 AUG 28,2003 12:23 PACIFIC 15:23 EASTERN ( BW)(MA-MCGOVERN-INSTITUTE) McGovern Institute Reports New Findings In Brain's System; Leading MIT Neuroscientists Describe Brain's 'Checklist' Business Editors/Health/Medical Writers CAMBRIDGE, Mass.--(BUSINESS WIRE)--Aug. 28, 2003--In a paper to be published today in the journal, Science, Dr. Naotaka Fujii, Research Scientist at MIT, and Dr. Ann M. Graybiel, Walter A. Rosenblith Professor of Neuroscience at the McGovern Institute at MIT, report what may be the brain's system for keeping track of what we do. We all admire people who keep checklists and check things off. Drs. Fujii and Graybiel suspect that they may have found the brain's check mark system and at least one brain site where the brain keeps its checklist. The checklist is in the prefrontal cortex of the brain, known for its ability to keep memories ready to use. Drs. Fujii and Graybiel recorded neural activity in the prefrontal cortex in monkeys that they had trained to make a simple series of movements. The neurons they recorded from faithfully responded with each movement, but they also had an "extra" response when the monkeys finished the entire sequence of movements. The experiments described in their report point to the extra response as being the checkmark - the brain's way to say that the behavior is done. Having an overactive checklist system could lead to some of the symptoms people suffer with damage to the frontal cortex. If the brain thinks actions are done and doesn't have the urge to do them, apathy can result. Such lack of drive can be a major symptom of frontal lobe dysfunction. At the other extreme, if the brain lacks its checkmark system, behavior may get repeated over and over again. Perseverative behaviors are a classic symptom of frontal lobe damage. It is as though the "it's done" signal is missing. Repetitive behaviors and thoughts are also features of obsessive compulsive disorder (OCD) and a range of related disorders that affect both children and adults. This work also suggests that the prefrontal cortex-basal ganglia brain regions that the researchers recorded from help "package" the individual parts of sequential behaviors into larger chunks. The same nerve cells that make the checkmark also accentuate their activity at the beginning of a movement sequence. A defect in this chunking system may underlie some of the symptoms of Parkinson's Disease, in which the patient has to think out each part of a sequence, even a "simple" movement sequence like standing up from a chair. Dr. Fujii is an ophthalmologist from Japan who has specialized in recording the activity of brain cells while primates carry out eye movement tasks. He was promoted to the rank of Research Scientist at MIT in 2001. Dr. Graybiel's groundbreaking research focuses on normal and abnormal behaviors associated with the basal ganglia, and their relationships to dopamine regulation. Dr. Graybiel studies the neurophysiology of the basal ganglia, a brain region that is implicated in the control of movement and cognition, as well as in our ability to learn habits. Disorders in this region have been implicated in Parkinson's and Huntington's diseases, and in neuropsychiatric disorders such as Tourette's syndrome, obsessive-compulsive disorder, depression, and also addiction. Dr. Graybiel joined the MIT faculty in 1973 and in 1994 was named Walter A. Rosenblith Professor of Neuroscience in the Department of Brain and Cognitive Sciences. In 2001, she was appointed Investigator at the McGovern Institute. She received her Ph.D. in 1971 from MIT. Graybiel is a member of the National Academy of Sciences, the Institute of Medicine, and the American Academy of Arts and Sciences. Graybiel was named a recipient of the 2001 National Medal of Science, the nation's highest science and technology honor. About the McGovern Institute at MIT ..... By determining how the brain works, from the level of gene expression in individual neurons to the interrelationships between complex neural networks, the McGovern Institute's efforts work to improve human health, discover the basis of learning and recognition, and enhance education and communication. The McGovern Institute contributes to the most basic knowledge of the fundamental mysteries of human awareness, decisions, and actions. For more additional information, please go to http://web.mit.edu/mcgovern --30--MB/bo* CONTACT: skyemedia, inc. Lyn Chamberlin, 978-443-0400 x11 [log in to unmask] KEYWORD: MASSACHUSETTS INDUSTRY KEYWORD: MEDICAL EDUCATION SOURCE: McGovern Institute SOURCE: Business Wire (press release) http://tinyurl.com/lkve * * * ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn