cerebellum

cerebrocerebellum

lateral cerebellar hemispheres

dentate nucleus

spinocerebellum

vermis and intermediate hemispheres

interposed nuclei

vestibulocerebellum

flocculus and noddulus

vestigal nuclei

function of cerebrocerebellum

precise rapid limb movement

augmentation of tasks requiring dexterity

movement initiation

motor learning

function of vestibulocerebellum

balance, coordination of eye and hand movement, control axial muscles/proximal stability

function of spinocerebellum

execution of limb movement; fine tuned motor control (interposed nuclei)

muscle tone regulation (fastigial nucleus)

deepest layer of cerebellar cortex

granule cell layer

middle layer of cerebellar cortex

purkinje cell layer

most superficial layer of cerebellar cortex

molecular layer

function of climbing fibers

involved in motor learning

arise from inferior olivary nucleus

excitatory to purkinje fibers, thus inhibitory to deep cerebellar nuclei

climbing fibers

change firing rate while learning new movements

function of mossy fibers

bring in sensory information and information form other motor areas

indirectly excites Purkinje cells via granule cell

vestibulocerebellum lesion

balance and righting problems

spinocerebellum lesion

ipsilateral hypotonic muscle

spinocerebellum lesion

ipsilateral coordination difficulties

ataxia, dysmetria, dysarthria, intention tremors

ataxia

overshooting, jerky movements

dysmetria

ataxia where judgement of distance is off

dysarthria

motor speech problem, understand but can’t mouth the words

intention tremor

when intending to do a task, there is a fine tremor

cerebrocerebellum lesion

rapid alternating movements

cerebrocerebellum lesion

problems with motor learning

cerebellar double cross

accounts for ipsilateral distal signs with a cerebellar lesion