General principles

In spite of the functional subdivisions, the similar circuit is repeated across the whole cerebellum; therefore it is likely that similar calculations are performed by all sections of the cerebellum. The cerebellum appears to be concerned with high accuracy timing of movements initiated by the motor cortex. Additionally the cerebrocerebellum can start movements, mainly in response to auditory and visual stimulation. In movements triggered in this way the order of activation is: dentate nucleus–motor cortex–interpositus nucleus–muscle. Moreover, central to the operation of the cerebellum is motor learning, the accomplishment of new motor skills.

In primates, parallel fibers average 6 mm in length and therefore affect a comparable length array of Purkinje cells (PCs) which lie across the cerebellum. This is adequately long to span a whole deep cerebellar nucleus or bridge adjacent nuclei. The PC arrays coupling both fastigial nuclei, for illustration, would assure coordination of postural muscles across the mid-line that is significant in gait. The PC arrays influenced by a given set of parallel fibers span muscles over numerous joints. This anatomical configuration supports the outcomes of recording and lesion studies displaying that the cerebellum is much more concerned with control of movements including many joints instead of single joints.

The cerebellum is considered to operate in one of two modes, feedback or feed-forward, depending on the situations.