9630867 Bishop The cerebellum is a part of the brain that controls and coordinates movement. Along with the cerebellum, there are several brainstem centers which receive information regarding the status of a movement. The information is initially processed in these centers and then relayed to the cerebellum where it is used in circuitry that ultimately fine tunes motor control. One of these brainstem centers that provides information to the cerebellum is a nuclear group called the inferior olivary complex. Any changes in the message sent out by the olivary complex will have a direct impact on cerebellar circuits which control movement. The intent of this study is to use anatomical and physiological techniques to better understand how two distinct classes of neuroactive chemicals, namely neuropeptides and monoamines, modulate the activity of neurons in the inferior olive. The anatomical studies will define the distribution of the peptide calcitonin gene related peptide, and the monoamine serotonin, both of which are known to be present and active in cerebellar circuits. In addition, we will use techniques to determine the brainstem source of these two neuroactive chemicals. The physiological studies are designed to determine how this neuropeptide and monoamine change the responsiveness of neurons in the olivary complex. In addition, we will analyze how these two distinct classes of neuroactive chemicals interact with each other to modify the way in which olivary neurons respond to inputs derived from other regions of the brain and spinal cord. An understanding of how olivary output is modulated by chemically defined inputs is critical for our understanding of how the olivocerebellar system functions in coordinating motor activity.
