The first goal of this research project is to identify the neurons that carry information from the cingulated cortex (indirectly) to the musculature involved in the production of vocalizations and motor tics. Once these neurons have been identified, much can be said about their neurochemistry and their connections with other brain regions. In addition, a naturally produced neural substance called dopamine is thought to play a role in Tourette Syndrome. The second goal of the research project is to determine whether the cingulated cortex neurons carrying information to the musculature are involved with dopamine. This will be done through the use of a protein called DARPP-32 which can now be used to mark such neurons. These studies are relevant to Tourette Syndrome for the following reasons. First, the cingulated cortex can initiate vocalizations and movements. This is especially interesting because the cingulated cortex is part of the “emotional brain,” and as such would be expected to regulate activity with emotional content. Second, neurosurgical patients report that movements and vocalizations induced by cingulated cortex stimulation carry with them a feeling of compulsion which cannot be easily resisted. Moreover, the movements elicited by cingulated stimulation closely resemble those seen in Tourette Syndrome. Third, stimulation of the anterior cingulated cortex often produces feelings of anxiety. Fourth, cingulate cortex is strongly implicated in obsessive/compulsive disorder, an associated behavior often seen in Tourette Syndrome patients. Fifth, anti dopamine drugs such as haloperidol can reduce the severity of symptoms in Tourette Syndrome, and the cingulate cortex is greatly involved with dopamine. Thus the identification of cingulated cortex neurons that influence motor tics and vocalizations and are involved with dopamine is germane to a better understanding of Tourette Syndrome. Charles C. Ouimet, Ph.D. The Rockefeller University, New York, NY Award: $25,000 Tourette Association of America Inc. – Research Grant Award 1987