Research is proposed which will investigate neurophysiological aspects of basal ganglia output influences on trigeminal motor and sensory neurons. Extracellular single unit and intracellular recording techniques will be used to assess the influence of BG output on resting trigeminal sensory and motor neuronal activity as well as to assess the degree to which basal ganglia influences on the motor system are mediated by sensory interactions. The combination of extracellular and intracellular techniques will provide information about the underlying synaptic mechanisms involved in the BG's modulation of trigeminal motor activity. This research will augment prior studies which assessed trigeminal sensory information processing in BG structures and the effects of BG lesions on trigeminal motor activities. The proposed study will also serve as part of a research plan designed to ultimately investigate physiological, pharmacological, and behavioral aspects of basal ganglia control of trigeminally-mediated motor behaviors. The problem of BG-trigeminal interactions is of relevance to both experimental and clinical areas of neuroscience. An understanding of these relationships will lead to an understanding of the nature of oral motor disturbances which accompany BG disorders and may provide background information prerequisite to the development of new therapeutic measures.