Climbing fibres send excitatory input to:

Functional unit of cerebellum = purkinje cell & corresponding deep nuclear cell. Afferents to cerebellum: - 1. Climbing fibers 2. Mossy fibers Climbing fibers all originate from the inferior olives of the medulla; forming the olivocerebellar tract. They are excitatory to the deep nuclear cell (excitatory) purkinje cell (inhibitory) | Precise output for motor movements Mossy fibers - afferents from various other sources send excitatory collateral to deep nuclear cell and proceed to excite granule cells. Granule cells send out extremely sho axons up to the molecular layer cerebellar coex where they divide into 2 branches running parallel to the folia, k/a parallel nerve fibers. Golgi cells, stellate cells & basket cells are inhibitory cells with sho axons, located in the molecular layer of cerebellar coex they send axons to adjacent purkinje cells & cause lateral inhibition, thus sharpening the output signal.