Cerebello-cerebral feedback projections

Abstract

The functional neuroanatomy of cerebellar systems has been extensively studied during the past decades by means of experimental animal studies, anatomoclinical studies, as well as structural and functional neuroimaging studies in patients and healthy subjects. Within a system of closed-loop circuits, this wealth of studies identifi ed reciprocal projections between the cerebellar structures and the supratentorial areas subserving sensorimotor, cognitive, and affective function. It has been shown that cerebellar output is mediated by the deep cerebellar nuclei, mainly by the dentate nucleus (DN), which project to the supratentorial cortex via the thalamus (cerebello-thalamo-cortical pathway). In turn, the cortical areas that are the target of cerebellar output project back to the cerebellum via the pons (cortico- ponto- cerebellar pathway). Regions of the cerebellar cortex that receive input from a specifi c supratentorial area, are the same regions that project back to that supratentorial area, thus forming closed-loop circuits. These projections are largely crossed, connecting the cerebral hemispheres primarily with the contralateral cerebellar hemispheres.