Unit 3_The Cerebellum Flashcards
What receives a lot of information and integrates it to help plan and modulate movement?
The cerebellum
What functional anatomical area of the cerebellum receives sensory information from the lateral cerebellar hemispheres (Planning and adaptation of movements)?
Cerebrocerebellum
What functional anatomical area of the cerebellum receives sensory information from the vermis (Axial & proximal muscles) and intermediate (distal limbs) cerebellar hemispheres?
Spinocerebellum
What functional anatomical area of the cerebellum receives sensory information from the flocculus and nodulus (posture and balance)?
Vestibulocerebellum
What is organized in functional modules and to connect with appropriate parts of CNS?
Cerebellum
What has a somatotopic organization?
Spinocerebellum
What functions include:
1. Balance
2. Coordination of eye and head movement in relation to position in space
3. Control axial muscles/proximal stability
VESTIBULOCEREBELLUM – Floculonodular lobe
What functions include:
1. Execution of limb movement; fine tuned motor control
a. Compensates for variation in loads
b. Smooths oscillations in movement
c. Corrects for deviation of an intended movement
2. Muscle tone regulation
OUTPUTS -
Interposed Nuclei – execution of movement
Fastigial Nucleus – Regulation of muscle tone
SPINOCEREBELLUM –
Vermis (Axial and Face) and
Intermediate zone (Limbs) Cerebellum
What functions include:
1. Precise rapid limb movement through regulation of agonist-antagonist timing
2. Augmentation of tasks requiring dexterity
3. Movement initiation
Motor learning
OUTPUT – Dentate nucleus to thalamus to cortex
CEREBROCEREBELLUM –
Lateral Cerebellar hemispheres
What are the 3 layers of the cerebellar cortex deep to superficial?
- Granule Cell layer
- Purkinje Cell layer
- Molecular layer
What are 3 important cell and fiber types?
- Purkinje cells
- Climbing Fibers
- Mossy Fibers
What important cell type is the following:
- main output cells from cerebellar cortex but NOT the cerebellum itself
- inhibitory to deep cerebellar nuclei
- reduces activity of tonically active deep cerebellar cells
Note: orientation of dendritic tree—it is like fingers coming off the palm of the hand.
Purkinje cells
What important fiber type is the following:
- involved in motor learning
- arise from inferior olivary nucleus in the open medulla
- excitatory to Purkinje cells thus inhibitory to deep cerebellar cells
- changes their firing rate while learning new movements
Climbing Fibers
What important fiber type is the following:
- arise from other all afferent sources besides the inferior olive- bring in sensory info and info from other motor areas.
- indirectly excites Purkinje cells via granule cell (interneuron)
Mossy Fibers
During learning the inferior olive shapes what?
the firing of Purkinje cells
