The cerebellum controls the maintenance of equilibrium posture
and muscle tone and it co-ordinates movement. It operates at an unconscious
level. The cerebellum is connected to the medulla, pons and midbrain by
the inferior, middle and superior cerebellar peduncles respectively.
The cerebellum consists of a midline vermis and two laterally
located hemispheres. Anatomically, the cerebellum is dived into anterior,
posterior and flocculonodular lobes.
Internally, the cerebellum consists of surface layer of cortex,
highly convoluted to form folia, beneath which lies white matter.
Within the white matter lid cerebellar nuclei (fasigial,
globsoe, emboliform and dentate). The nuclei are the origin of cerebellar
The archicerebellum corresponds to the flocculonodular lobe
and fastigial nucleus. Its principal connections are with the vestibular
and reticular nuclei of the brain stem and its is concerned with the maintenance
The paleocerebellum corresponds to the vermis and paravermal
area, together with the globose and emboliform nuclei. it receives fibres
form the spinocerebellar tracts and projects to the red nucleus of the
The neocerebellum corresponds to most the cerebellar hemisphere
and the dentate nucleus. It receives afferents from the pons and projects
to the ventral lateral nucleus of the thalamus.
Cerebellar lesion cause incooridnation fo the upper limbs
(intention tremor), lower limbs (cerebellar ataxia), speech (dysarthria)
and eyes (nystagmus).
The cerebellum is supplied by the superior cerebellar, anterior
inferior cerebellar and posterior inferior cerebellar arteries. These arteries
are branches of the basil artery.