Grant: Operating Grant

The cerebellum is a highly organized structure that rests near the back of the brain to coordinate all aspects of movement. It receives sensory input from joints and muscles during movement that inform the circuit of where in space a limb is positioned, and the current status of a requested movement (ie arm or leg). Sensory input is received by the cerebellar cortical circuit that is centered around a layer of Purkinje cells. All output from Purkinje cells is then transmitted to a set of three Deep Cerebellar Nuclei (DCN) as a series of electrical impulses down its nerve fiber, with the DCN in turn taking charge of sending all final output from cerebellum to various motor centers. What makes the cerebellum unique is that all Purkinje cell output to the DCN is inhibitory, meaning that DCN cells must translate an inhibitory signal to an excitatory output that reflects the pattern or frequency of arriving nerve impulses. We use recordings of single cells in animal model preparations to understand the "neural code" used by DCN cells to translate Purkinje cell inhibition into an excitatory "rebound excitation" that accurately reflects incoming information. In this way we can understand where the circuit fails to function correctly in cases of ataxia or tremor.