Cerebellum Flashcards
where in the skull is the cerebellum located
posterior cranial fossa
what type of control does the cerebellum display
ipsilateral
longitudinal divisions of the cerebellum
- vermis
- paravernal region
- cerebellar hemispheres
transverse divisions of the cerebellum
- anterior lobe
- posterior lobe
- floccunlonodular lobe
two main divisons of the cerebellum
- primary fissure
- posterolateral fissure
what does the primary fissure divide
anterior and posterior lobes
what does the posterolateral fissure divide
the posterior and flocculonodular lobes
what does the superior peduncle connect the cerebellum to
superior pons/midbrain
what type of projections does the superior peduncle have
efferent (output)
what does the middle peduncle connect the cerebellum to
pons
what type of projections does the middle peduncle have
afferent (input)
what does the inferior peduncle connect the cerebellum to
medulla
what type of projections does the inferior peduncle have
both afferent and efferent (input and output)
name the four cerebellar nuclei
- dentate
- globose
- emboliform
- fastigial
where is the dentate nucleus found
cerbellar hemisphere
where is the globose nucleus found
paramedian zone
where is the emboliform nucleus found
paramedian zone
where is the fastigial nucleus found
vermis
two projections to the cerebellum
- cerebral cortex → pons (pontocerebellar tract) → middle cerebellar peduncle → cerebellar cortex
- vestibular nuclei/inferior olives/dorsal nuclei of Clark → inferior cerebellar peduncles → cerebellar cortex
two projections from the cerebellum
- cerebellar cortex → fastigial nuclei → inferior cerebellar peduncle → vestibular nuclei
- globose nuclei/emboliform nuclei/dentate nuclei → superior cerebellar peduncle → thalamus → primary motor and premotor cortex
three functional divisions of cerebellum
- vestibulocerebellum
- spinocerebellum
- cerebrocerebellum
what is the vestibulocerebellum also known as
archicerebellum
afferent projections of vestibulocerebellum
- via inferior peduncle from vestibular apparatus and vestibular nuclei
- via middle peduncle from primary visual cortex and superior colliculus
efferent projection of vestibulocerebellum
via inferior peduncle to vestibular nuclei
functions of vestibulocerebellum
- influences vestibulospinal tracts that control postural muscles
- influences the vestibulo-occular reflex
- maintains equilibrium
what is the spinocerebellum also known as
paleocerebellum
afferent projection of spinocerebellum
via inferior peduncle from spinal cord (somatotopic organization)
efferent projections of spinocerebellum
- paramedian zone: interposed nuclei → inferior peduncle → red nucleus → thalamus → motor cortex
- vermis: fastigial nucleus → superior peduncle → vestibular nuclei/reticular formation/motor cortex
functions of spinocerebellum
- paramedian zone: influences lateral muscles (limbs)
- vermis: influences axial muscles and facial/tongue muscles
- tells CNS about the state of your muscles (proprioception)
what is the cerebrocerebellum also known as
neocerebellum
afferent projection of cerebrocerebellum
via middle peduncle from cortex and pontine nuclei (ie the corticospinal tract)
efferent projections of cerebrocerebellum
Dentate nucleus → superior peduncle → red nucleus → thalamus → motor cortex
functions of cerebrocerebellum
- influences corticospinal and corticobulbar tracts to regulate complex movements
- influences cerebellum for motor learning
- tells cerebellum what cortex is doing or planning to do
four causes of cerebellar dysfunction
- physical trauma
- interruption of blood supply/stroke
- alcoholism (affects Purkinje cells in anterior lobe)
- tumours/cancer (degeneration of Purkinje cells)
clinical presentation of cerebellar dysfunction
- Dysdiadochokinesia (difficulty carring out rapid, alternating movements)
- ataxia
- nystamgmus
- intention tremour
- scanning speech
- hypotonia
