The study of Tourette Syndrome with new technologies such as PET scan has provided new information about areas of the brain possibly involved in symptoms. Computer-based electrophysiology (CEEG) permits a functional measure of ongoing brain activity by completely noninvasive means. The use of a large array of electrodes permits mapping of electrical activity of the brain in a variety of ways without discomfort or significant interference with the individual. Studies of this type can provide systematic insight into anatomical areas of the brain that are functioning in unusual ways, and that can account for symptoms of the individual subject. The studies we are conducting involve the baseline study of each TS individual, and a matched control subject separately. Following baseline measures, each individual will be given a natural substance orally that selectively increases the activity of a particular neurotransmitter substance in the brain. It is our hope that the study of controls and TS subjects under these baseline and “challenge” conditions will provide new information about the functional localization of central nervous system neurotransmitter systems, and how these differ in the individual TS subject. Our hope is that this procedure may ultimately provide, moreover, a unique and noninvasive manner in which to determine the individual TS subject’s potential for side effects of certain drugs. One long-range goal is to begin to develop ways to assess the pharmacology and neuropsychological treatment most likely to be effective in the control of the Tourette Syndrome individual’s symptom cluster. Kenneth A. Bonnet, Ph.D., Research Associate Professor of Psychiatry, Millhauser Labs New York University School of Medicine, New York, NY Award: $15,000 Tourette Association of America Inc. – Research Grant Award 1986