Cerebellum Function and Anatomy Quiz

Cerebellum Function

• The cerebellum regulates voluntary movement and posture, indirectly adjusting the output of the brain's major descending systems.
• It also plays a role in motor learning.
• Cerebellar lesions disrupt eye and limb movements, impair balance, and decrease muscle tone.
• The cerebellum comprises 10% of the brain's total volume, yet it contains over half of the brain's neurons.
• The cerebellum helps provide smooth, coordinated body movement.

Cerebellum Location and Relationships

• The cerebellum is located at the back of the brain, beneath the occipital lobes and above the brainstem.
• The cerebellum is separated from the cerebrum by the tentorium cerebelli.
• The cerebellum is connected to the brainstem by three pairs of cerebellar peduncles (superior, middle, inferior).
• The cerebellum is covered by the dura mater, arachnoid mater, and pia mater meninges.
• It sits nestled within the posterior fossa of the skull.

Cerebellar Nuclei

• The cerebellum comprises several deep nuclei, including the fastigial, globose, emboliform, and dentate nuclei.
• These nuclei are involved in coordinating motor commands and relaying information to the cerebral cortex.

Cerebellar Afferents

• The cerebellum receives information from sensory receptors in the body (muscle spindles, Golgi tendon organs).
• Information also comes from the vestibular system (balance) via the vestibulocerebellar tract to help with posture and coordination of movement.
• Input also comes from the cerebral cortex.
• Information from the spinal cord arrives through anterior and posterior spinocerebellar tracts and cuneocerebellar tracts..

Cerebellar Efferents

• The cerebellum sends information to the motor cortex via descending pathways, predominantly through the deep nuclei.
• Some efferent pathways also lead to the red nucleus
• The deep cerebellar nuclei (dentate, emboliform, globose, fastigial) play a crucial role in regulating motor commands and other important activities.

Cerebellar Arteries

• Blood supply to the cerebellum comes from three main arteries:
  • Posterior inferior cerebellar artery (PICA) - branch of vertebral artery
  • Anterior inferior cerebellar artery (AICA) - branch of basilar artery
  • Superior cerebellar artery (SCA) - branch of basilar artery

Cerebellar Venous Drainage

• Cerebellar veins drain into the superior vermian vein, which further drains to the great cerebral vein of Galen, then into the straight sinus.
• Some veins also drain into the transverse sinus.
• Inferior vermian veins drain to the straight sinus.
• Superior and inferior cerebellar hemispheric veins empty into the transverse sinus. Some cerebellar venous blood also drains into the posterior spinal vein.

Cerebellar Function & Disorders

• The cerebellum is vital for controlling posture, balance, and coordinated movement.
• Ataxia, tremors, nystagmus, and dysarthria are examples of disorders that indicate cerebellar dysfunction.
• Specific tests assess cerebellar function (finger-nose test, tandem gait, Romberg's test, etc).