• The anterior cerebellar lobe
  • The posterior cerebellar lobe
  • The flocculonodular lobe: nodule in midline and flocculus out laterally.
  • The midline cerebellum is the vermis (which means wormlike)
  • Lateral to it, lies the paravermis (aka the intermediate zone)
  • Lateral to it, lies the hemisphere (aka the lateral zone)
  • Phylogenetically the oldest portion of the cerebellum and is referred to as the archicerebellum.
  • It is derived from the flocculonodular lobe and the anterior tip of the vermis (the lingula).
  • The vestibulocerebellum receives its name because of its midline vestibulo- and olivocerebellar fibers, which project to the deep, medial-lying cerebellar fastigial nuclei.
  • It is important for equilibrium and eye movements.
  • Phylogenetically the next oldest and is referred to as the paleocerebellum.
  • It is derived from the anterior lobe and the majority of the vermian and paravermian posterior lobe.
  • The spinocerebellum receives its name from its major input fibers: the spinocerebellar tracts.
  • It plays a major role in postural stability.
  • Phylogenetically the newest portion of the cerebellum and is referred to as the neocerebellum.
  • It is derived from the remainder of the posterior lobe.
  • The pontocerebellum receives its name because it acts through the corticopontocerebellar pathway.
  • It is geared towards fine motor movements, which are typically goal-oriented.
  • Nystagmus occurs from toxicity to the vestibulocerebellum, truncal ataxia occurs from toxicity to the spinocerebellum, and incoordination occurs from toxicity to the pontocerebellum.
  • The pathology is predominantly restricted to the anterior superior cerebellar vermis. Because of this restricted area of injury, truncal ataxia is sometimes the sole deficit.
  • Unilateral cerebellar lesions affect the ipsilateral side of the body.
  • The midline cerebellum plays a role in posture whereas the lateral cerebellum assists in fine motor, goal-oriented skills.
  • For instance, to stand upright, you need the midline cerebellum, and to play the piano, you need the lateral cerebellar hemispheres.
  • The somatotopic map of the cerebellum is in concert with its functional layout: the role of the spinocerebellar, anterior lobe is to provide postural stability, which requires the limbs and trunk, and the role of the neocerebellar, posterior lobe is to provide goal-oriented, fine motor movements, such as those of the fingers and mouth.