Cerebellum

Abstract

The cerebellum is a very distinct region of the brain, occupying a position immediately behind the tectal plate and straddles the midline as a bridge over the fourth ventricle. The basic functional design of the cerebellum is that of an interaction between two sets of different neuronal elements: those of the cortex and those in the centrally located cerebellar nuclei. The cerebellar cortex receives two types of afferents, the climbing fibers and the mossy fibers, and generates a single output system, the axons of Purkinje cells. The cerebellar nuclei receive collaterals from the climbing and mossy fibers and are the main targets for the Purkinje cell axons. The cerebellum as a whole is connected to the rest of the central nervous system by three large fiber bundles, the cerebellar peduncles. This chapter discusses the general organization of the cerebellum, covering its neuronal elements, synaptic connections, basic circuit organization, intrinsic membrane properties, synaptic actions, dendritic properties, and functional circuits.