Cerebellum

Cerebellum:
Largest part of hindbrain (10% of total brain volume, but has 50% of neurons) - located posterior dorsal to pons and medulla (seperated from them by the 4th ventricle) and under occipital lobes of cerebral hemispheres in posterior cranial fossa of skull. Consists of two hemispheres connected by ‘wormlike’ vermis. Each hemisphere has 3 morphologically distinct lobes (anterior, posterior and the flocculonodular lobes). Connected to brainstem by 3 pairs of ‘cerebellar peduncles’ (inferior peduncles  medulla oblongata; middle peduncles  pons; superior peduncles  midbrain). Resemble the branches and truck of a tree (arbor vitae).
Three layers – molecular layer (two types of neurons – stellate cells and basket cell with glial cells); Purkinje cell layer (most prominent; consists of single layer of Golgi type 1 neurons); and granular layer (small cells with 4-5 dendrites; closest to white matter)
Receives most of input from pons.
Function is to process information from cerebral motor cortex, from proprioceptors, visual and equilibrium pathways  provides instruction for balance, posture and smooth co-ordinated movements. Plays a major role in motor learning.

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