Cerebellum Ojemann Flashcards
what does the cerebellum do
calibration of reflexes
vestibular occular rflex
controls eye movements to coordinate movement of eyes with movement of head. ie, move head eyes stay fixed on same target.
If you loose hair cell in vestibular apparatus, this reflex would become weakened However, the cerebellum makes sure this doesn’t happen. mossy fibers from vestibular aparatus to cerebullum, then fibers from cerebellum to eye muscles
inputs heading to cerbellumn
balance/position/etc - mossy fibers
error inputs - climbing fibers from medulla, contralateral inferior olivary nucleus
cerebellar threes
3 gross divisions (2 hemispheres, and a vermis)
3 peduncles
3 functional divisions
3architectural features (cortex, white matter, deep nuclei)
3 cortical layers (molecular, purkinje, granule)
3 principle information processing cells (purkinje, granule, DCN)
3 step circuit
3 general effects of cerebellar damage
3 goss divisions
two hemispheres and one vermis, the vermis is tots divided into three as well. nodulus is part of foccular nodular lobe
3 peduncles
middle CP - all in put structures (mossy fibers)
inferior CP - from medulla (climbing fibers)
superior CP - fibers from midbrain
3 phylogenetic divisions
archicerebellum - flocculus
paleoceebellum - spinalcerebellum
neuocerebellum - cerebocerebellum
where do perkinje cells signal to?
to the DCN
parallel fibers?
from granular cells, make these t shaped axons that signal to perkinje cells
order of signaling in the cerbellum
granular cell signal to perkinjes through parallel fibers, perkinjes signal to dcn
climbing fibers
from contralateral inferior olivary nucleus, innervate perkinjes cells, innervate microsomes (stripes), tend to innervate the soma multiple times. Make complex spikes.
mossy fibers and granualr cells
mossy fibers signal to granular cells, which then contact perkinje cells, makes simple spikes
what happens when both granual and climbing fibers signal on the same perkinje fibers at the same time?
long term depression.
midline vermis input and output
output - vastigial nucleus
input - pusture stuff
spinal cerebellar inut and output
look it up