Lab 8 - Higher Motor Function

Cerebellum and Brainstem

The cerebellum is comprised of the cortex, which is visible in gross inspection, and the underlying cerebellar nuclei. The cerebellar cortex consists of a midline band, the vermis, and two expanded lateral lobes or hemispheres. By looking at the inferior surface of the cerebellum, the sharpest differentiation between the vermis and cerebellar hemispheres may be made. Note the spatial relationships of these cerebellar structures to the underlying brain stem.

On the superior surface, find the primary fissure separating the anterior lobe from the posterior lobe.

Inferiorly, you can see the posterolateral fissure, which separates the flocculonodular lobe (flocculus + nodulus) from the posterior lobe.

Three pairs of fiber bundles, the cerebellar peduncles, carry information to and from the cerebellum. Note that the superior cerebellar peduncle is the major efferent tract out of the cerebellum.

Recall that the fibers of the middle cerebellar peduncle arise from the pontine nuclei.

The inferior cerebellar peduncle connects the cerebellum with the medulla and spinal cord.

Cerebellum and Brainstem