Rhythm processing in the cerebellum and basal ganglia

When perceiving rhythm, we anticipate the occurrence of the next stimulus, focus our attention on that moment, and in some cases generate synchronized movement to the rhythm. The cerebellum and basal ganglia are known to be involved in rhythm processing, but their specific roles remain unclear. We recently found that neurons in the dentate nucleus of the cerebellum and the caudate nucleus of the striatum exhibited periodic activity as monkeys prepared eye movements for the omission of regularly repeated visual stimuli. When the locations of repetitive stimulus and saccade target were independently selected on each trial, periodic activity in the cerebellum was modulated by the location of the repetitive stimulus and that in the striatum by the location of the saccade target. These results suggest that internalized rhythms without movement are maintained as sensory information in the cerebellum and as motor information in the striatum.