In our previous study funded by TSA, we have shown, using anatomical and biochemical methods, a functional pathway between two brainstem areas which allows us to understand why two dissimilar drugs such as haloperidol (Haldol) and clonidine (Catapres) may both be of benefit in the treatment of Tourette’s Syndrome. However, we had hypothesized that an additional neuronal system was also involved and speculated that it might use a peptide called substance P as its chemical messenger. We are currently defining the precise anatomical interactions of our brainstem pathway with substance P neurons examining the functional modulation of our previously defined pathway by substance P, and also attempting to establish if induced changes in our pathway will reliably result in certain behavioral signs (e.g., stereotypy or tics). If these behavioral signs occur, we would then have an animal model for TS which could then help identify more specific and effective treatments for this disorder. Ariel Y. Deutch, Ph.D., Dept. of Pharmacology Yale Univ. School of Medicine Award: $16,350 Tourette Association of America Inc. – Research Grant Award 1986