Cerebellar Function Flashcards
(26 cards)
Define: Titubation
Tremor of the entire trunk or head during stance or gate.
What are the inputs to the vestibulocerebellum?
Primary afferents from vestibular labyrinth/nuclei.
Indirect visual inpur from sup. colliculi and striate cortex.
What is the output from the vestibulocerebellum?
Mainly to vestibular nuclei and fastigial nucleus.
What is the function of the vestibulocerebellum?
Controls eye movements and position of the head.
regulates gait and posture.
What is seen in lesions involving the vestibulocerebellum?
Ataxic gait (wide stance) Eye movement disorders.
What are the inputs to the spinocerebellum vermis portion?
Somatosensory from spinal cord axial proximal body parts.
Vestibular inputs
Facial, visual, auditory input to posterior lobe only.
What are the outputs of the spinocerebellum vermis portion?
Via fastigial nucleus to: Medial motor systems Vestibular nucleus Reticular formation Motor cortex
What is the function of the spinocerebellum vermis portion?
Regulates axial and proximal musculature.
Concerned with ongoing motor execution and regulation of muscle tone.
What is seen in lesions of the spinocerebellum vermis portion?
Decreased muscle tone
Decreased proximal and axial musculature.
Problems with ongoing motor execution.
What are the inputs to the spinocerebellum paravermal region?
Somatosensory from distal body parts.
Input from primary and somatic sensory cortex.
What are the outputs of the spinocerebellum paravermal region?
Via intopositus to:
Lateral motor systems
Red nucleus and motor cortex
What is the function of the spinocerebellum paravermal region?
Regulates distal muscle.
What is seen in lesions affecting the spinocerebellum paravermal region
SEEN IPSILATERALLY TO LESION CAUSING HYPOTONIA.
What are the inputs to the cerebrocerebellum AKA pontocerebellum?
Cortical afferents via the pontine nuclei.
What are the outputs of the cerebrocerebellum?
Via dentate nucleus:
- To lateral nucleus of thalamus and red nucleus
- Ventral lateral thalamus then projects to the premotor and primary motor cortex.
What is the function of the cerebrocerebellum?
- Preperation for movement.
- Multi joint movement
- Patients ability to judge elapsed time in non motor task.
What is seen in lesions to the cerebrocerebellum?
Delay initiating and terminating movements.
Problems with multijoint movement.
Cant judge elapsed time with non-motor tasks (can improve with eyes closed
What function do purkinje cells have?
Only cell to project out of cerebellar cortex.
What function do Granule cells have?
Only excitatory cells in cerebellar cortex.
What function do Golgi cells have?
Affect dendritic input to perkinje cells by inhibiting granular cells.
What function do stellate cells have?
Affect dendritic integration of purkinje cells.
What function do Basket cells have?
Make inhibitory synapses near initial segment of the purkinje cell axon.
How do mossy fibers affect perkinje cells?
Indirectly sends excitatory signals to the granule and golgi cell dendrites. The granule cells are then able to excite the purkinje cells with small ESPSs.
LEARNING
Where do climbing fibers originate?
Inerior olivary nuclei
Each Purkinje cell only makes one synapse onto a climbing factor. Climbing factors synapse with multiple purkinje cells.
