Cerebellum-Gibson Flashcards
Key functions of the cerebellum are
1) Coordinates and smooths out muscle activity
2) movement of head, trunk, and limbs
T or F: Cerebellum initiates movement
False; it only COORDINATES movement
The tentorium cerebelli separates…
Cerebellum from cerebral hemispheres
Cerebellum sits above…
The 4th ventricle and brainstem
Define “Folia”
Small folds on the cerebellar surface
Define “Fissures”
Larger crevices between the folia
What is another name for the white matter in the cerebellum?
Arbor vitae
What is the vermis of the cerebellum?
The central medial region
What muscles and action is the vermis of the cerebellum associated with?
1) trunk muscles
2) proximal limb movement
Which input pathway is associated with the vermis of the cerebellum?
Spinocerebellar Pathway
What actions are the lateral hemispheres of the cerebellum associated with?
1) skilled movement
2) muscle function on the IPSILATERAL side
What input pathway are the lateral hemispheres of the cerebellum associated with?
Cerebrocerebellar pathway
Where is the Flocculonodular lobe of the cerebellum located?
Ventrally
What are the 2 main functions of the Flocculonodular lobe of the cerebellum?
1) Balance
2) Active in vestibular system
What input pathway is the Flocculonodular lobe associated with?
Vestibulocerebellar pathway
What are the 3 peduncles that attach the cerebellum to the brainstem bilaterally?
Rostral, Caudal, and Middle Cerebellar Peduncles
What structures of the brain are each of the 3 cerebellar peduncles associated with?
Middle- pons
Caudal- medulla
Rostral- midbrain
The 3 cerebellar peduncles are composed of…
Axons entering and exiting the cerebellum
Define “altricial”
Helpless, immature offspring due to cerebellum being underdeveloped at birth
Define “precocial”
Animal can ambulate and move on its own because the cerebellum has developed enough.
Where is the grey and white matter located in the cerebellum?
Grey- outside
White- inside
Name the layers of the cerebellar cortex from inner to outer
1) Granular cell layer
2) Purkinje cell layer
3) Molecular layer
What is special about the Purkinje layer of the cerebellar cortex?
1) only neuron with output from cortex to deep cerebellar nuclei
2) inhibitory neurotransmitter
The deep cerebellar nuclei contains extra gray matter. It is significant because…
1) send signals out from cerebellum
2) has excitatory neurotransmitters
Describe the locations and name the 3 parts of the deep cerebellar nuclei
1) Fastigial (Most medial)
2) Interposital (between fastigial and lateral
3) Lateral (self explanatory)
What are the deep cerebellar nuclei excitatory to?
Upper motor nuclei of pyramidal and extrapyramidal motor systems
Describe the 2 ways info can enter the cerebellum
1) cerebellum receives afferent sensory info from proprioceptors via body and head
2) cerebellum receives info from motor planning centers of forebrain
Describe the steps how info exits the cerebellum
1) info is sent to brainstem from cerebellum
2) info is then sent to motor cortex and pre-motor cortex to help coordinate and smooth out planned motor activity or out to body
Which region of the cerebellum does the spinocerebellar pathway reside and where does it eventually lead to?
Vermis; descending brainstem
Which region of the cerebellum does the cerebrocerebellar pathway reside and where does it eventually lead to?
Cerebral hemispheres; motor cortices
Which region of the cerebellum does the vestibulocerebellar pathway reside and where does it eventually lead to?
Flocculus; vestibular nuclei
What is the function of the spinocerebellar pathway, where is the info relayed to/ path of travel and what does it assist with?
1) general and subconscious proprioception
2) travels up ipsilateral cerebellum via spinocerebellar pathway
3) info assists with coordinating posture and locomotion
What is the function of the cerebrocerebellar pathway and which side does the info come down from?
1) critical for planning and control of precise movement of extremities
2) comes down from contralateral cortex
What is the function of the vestibulocochlear pathway?
Coordinates position of eyes, neck, trunk, and limbs with position and movements of head (ipsilateral)
All afferent signals entering the cerebellum are…
Excitatory
List the excitatory pathways of the cerebellum
1) spinocerebellar
2) cerebrocerebellar
3) vestibulocerebellar
Input from the extrapyramidal motor systems regulate…
Movement, posture, and locomotion
The efferent signals exiting the cerebellum are…
Inhibitory
Where do the inhibitory cerebellar signals synapse?
Mostly on deep cerebellar nuclei
Deep cerebellar nuclei are excitatory to…
Nuclei of pyramidal and extrapyramidal motor systems
Name 3 clinical signs of cerebellar disease
1) intention tremor
2) hypermtria
3) truncal ataxia
