6d Somatic Motor System

Where is the cerebellum relative to the brainstem?

Dorsal

What is the function of the cerebellum?

• Sensory-motor coordination of ongoing sequential movements

• Receives afferents from vision, vestibular apparatus, proprioceptors, and motor cortex

• Coordinated thought & Strategy

What are the 3 functional areas of the cerebellum.

• Cerebrocerebellum or Neocerebellum

• Spinocerebellum

• Vestibulocerebellum (Flocculonodular node)

Damage to the Vestibulocerebellum/Flocculoonodular node presents as what?

Presentations resembling lesions in vestibular apparatus: Balance issues and Nystagmus

Etiologies for cerebellar disease are what?

• Alcohol

• Stroke

• Trauma

• Astrocytoma: type of tumor affecting children

• Multiple Sclerosis

• Vit B12, Vit E, and thiamine deficiency

• Degenerative disease

• Infections

• Genetic

Presentations of Cerebellar Disease

General Patterns:

• Ipsilateral

• Hours or days of imbalance/dizziness/ vertigo with spontaneous nystagmus

Presentations:

• Ocular disturbances

• Ataxia: in-coordination of movement and thought

What are some ocular disturbances of cerebellar disease?

• Impaired smooth pursuit, not being able to foveate on a moving object

• Nystagmus: bidirectional horizontal nystagmus, nystagmus changes direction with changes in gaze; can have a down-beat nystagmus

What are some ataxia issues a patient with cerebellar disease can present?

• Gait; staggering or unable to tandem gait

• Dysmetria: instability as limb approaches target

• Intention tremor: tremor increases in magnitude as target is approached

• Dysdiadochekinesia: impairment of rapid, supinationand pronation of the hand

• Pendular knee jerk reflex

• Dysarthria: scanning speech in which words are broken into syllables

Know the lateral and anterior corticospinal tract.