Cerebellum Flashcards
The cerebellum does what 3 basic functions?
- sequencing complex movements
- postural adjustments
- modifying motor programs
What are the 3 lobes of the cerebellum?
- anterior - mm tone
- posterior - coordinates movement
- flocculonodular - balance and eye movements
If pressure increases on the cerebellar tonsils, what can happen?
pinch medulla
- leading to cardio/respiratory consequences
what is the output apparatus of the cerebellum?
Deep cerebellar nuclei
what is the acronym for cerebellar nuclei from LATERAL to MEDIAL?
Dont eat greasy food
- Dentate
- Eboliform
- Globose
- Fastigial
Eboliform and Globose are both in Interposed Nucleus
Acronym for layers of cerebellar cortex. From LATERAL to MEDIAL
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- Molecular
- Purkinje
- Granular
What occurs in Purkinje cell layer?
- forms output of cerebellar cortex
- INHIBIT deep cerebellar nuclei
what occurs in granular cell layer?
- granular cells receive input from Mossy fibers
- which then synapse on pukinje cells
Does cerebellum analyze ipsi or contra info?
Ipsi only
What do purkinje cells do?
long term inhibition of deep cerebellar nuclei
What are the two afferent fibers called?
- Inferior Olivary fibers - Climbing
- Mossy fibers
Are they both excitatory or inhibitory?
Both excitatory
What do Mossy fibers do?
One axon has excitatory influence MANY purkinje cells
What do (olivocerebellar) climbing fibers do?
One axon has powerful excitatory input on Purkinje cells
- which in turn will INHIBIT DCN
- allows system to adjust instantaneously if something perturbs planned movement
- fires less with learning
What are the 3 cerebellar peduncles? and what are there efferent/afferent pathways?
- Superior - efferent and some afferent
- Middle - afferent
- Inferior - afferent and some efferent
what 3 pathways are in superior?
- Dentatorubrothalamic
2. ventral and rostral spinocerebellar
What does the Dentatorubrothalamic pathway do?
- efferent
- learned motor behavior
What occurs in SCP?
- crossing
- pathway crosses twice- once at segmental level & then through SCP to travel ipsilaterally to Cerebellum
What fibers run in middle cerebellar peduncle?
Where does it receive info?
- afferent
- Pontocerebellar
- from all parts of cortex
What fibers and pathways are found in inferior peduncle?
-afferent and some efferent Dorsal & cuneocerebellar pathways Olivocereblellar Trigeminocerebelzar Vestibulocerebellar Fastigiovestibular
What do cuneocerebellar pathways do?
carry specific joint and mm info encoded by GTO’s, mm spindles, joint capsule receptors
What do Olvocerebellar pathways do?
from olivary complex
Give rise to climbing fibers
What does trigeminocerebellar pathway do?
carry info from face, jaw, eye mm
What does vestibulocerebellar pathway do?
axons from vestibular nuclei as well as direct fibers form vestibular apparatus
what does fastigiovestibular pathway do?
carries an efferent pathway from fastigial and interposed nucleus to vestibular nuclei
what are the 3 divisions of cerebellum?
- vestibulocerebellum
- spinocerebellum
- cerebrocerebellum
what does vestibulocerebellum do? and what Lobe is it found in?
Controls postural tone & balance
-also controls extra ocular eye movements,
Flocculododular lobe
Where do efferent go through for Vestibulocerebellum?
inf. cerebellar peduncle
Where does Vestibulocerebellum get its info from and what does it do with it?
Gets it from vestibular nucleus and sends it back to influence vestibular function and reticulospinal pathways
Where is spinocerebellum located (lobe) and what does it do?
Vermis and paravermal zones - anterior lobe
- Muscle tone
- also controls limb movement for error correction resulting in coordinated movements
What info comes from the spinal cord and into the Spinocerebellum?
auditory, visual, vestibular, trigeminal, motor cortex
what 2 tracts are found in the spinocerebellum? are they efferent or afferent?
efferent
DSCT
VSCT
Dorsal and ventral spinocerebellar tract
What does the cerebrocerebellum do and what lobe is it found in?
Coordination of movement
- posterior
- also memory of movements
What hemispheres is cerebrocerebellum found in?
Lateral
Where does cerebrocerebellum send its efferent info to? and through what tract?
motor and premotor cortex
-dentatorubrothalamic pathway
