Cerebellum Flashcards
Functions of the cerebellum
Coordination (limb, trunk, and oculomotor) Balance and equilibrium Muscle tone Motor control Motor learning
Where is the cerebellum located
In the posterior fossa
Infratentorial
Dorsal to the midbrain (4th ventricle)
What does the primary fissure separate
Anterior and posterior lobes
What does the posterolateral fissure separate
Separates the flocculonodular lobe and posterior lobe
Describe the fibers that go through the SCP
Primarily efferent, some afferent, fibers between the midbrain and the cerebellum
Describe the fibers of the MCP
Afferent fibers from Pons to the cerebellum
Describe the fibers of the ICP
Afferent and efferent fibers between the medulla and cerebellum
Where does the superior cerebellar peduncle decussate
Caudal midbrain at the level of the inferior colliculi
Describe the input in the cerebrocerebellum and what this region is involved in
Input to/from cortex
Involved in planning and initiation of movement
What are the 3 cerebellar regions
Cerebrocerebellum
Spinocerebellum
Vestibulocerebellum
Describe the spinocerebellum’s input/output and what it is involved in.
Input to/from SC
Vermis: posture, proximal limb movement, eye movement
Intermediate zone: appendicular limb position and somatosensory input
Describe the vestibulocerebellum in terms of input and involved functions
Inputs to/from vestibular labyrinth
Maintenance of equilibrium, balance and posture, Vestibulo-ocular control
The cerebellum provides ____________ effects on motor function
Modulatory (inhibitory)
What is the main cell of the cerebellar outputs
Purkinje cells
What two fibers are involved in cerebellar inputs
Pontocerebellar fibers
Olivocerebellar fibers
What are the pontocerebellar fibers involved in and what cortices contribute to these fibers?
Involved in planning and control of prescient dexterous movements of the extremities
Cortices: PriMC, PriSC, visual cortex (also vestibular and auditory)
Olivocerebellar fibers are involved in…
Motor learning and motor memory
The pontocerebellar fibers travel through the ______ cerebellar peduncle and the Olivocerebellar fibers travel through the _________ cerebellar peduncle
Middle
Inferior
What are the spinocerebellar pathways
Afferent pathways to the cerebellum from the SC
Dorsal spinocerebellar tract
Cuneocerebellar tract
Ventral spinocerebellar tract
Rostrum spinocerebellar tract
Which spinocerebellar tract sends afferent info amount LE limb movements (subconscious perception from interfusal and jt receptors)
Dorsal Spinocerebellar tract
What tract hold afferent info about UE and neck movements (subconscious perception from intramural and jt receptors)
Cuneocerebellar tract
What tract sends afferent info abou the LE SC interneurons from intrafusal fibers and GTOs
Ventral Spinocerebellar tract
Afferent info about activity of US/neck SC interneurons from intrafusal fibers and GTOs is sent via what track
Rostrum spinocerebellar tract
What are the steps of the dorsal spinocerebellar tract
LE prprioceptors> dorsal root > dorsal horn > synapse on nu dorsal is of clark > up sc to rostral medulla >ICP to cerebellar cortex
Where is the nu dorsal is of clark located
C8-L2/3
Describe the Cuneocerebellar tract
UE/neck proprioceptors > dorsal root> dorsal horn> up dorsal column and synapse in ext cuneatus nu (caudal medulla) > ICP > cerebellar cortex
Ventral and Rostral spinocerebellar tracts travel the same except the Ventral carries info from _____ and Rostral carries info from ______
LE
UE
Go through the ventral/rostral spinocerebellar tracts
LE/UE proprioceptors (respectively) synapse with ipsilateral spinal interneurons > decussate via ventral commissaries and ascend in lateral columns of SC, through the braisten to sup. Colliculus >decussate again via SCP and travel to cerebellar cortex
Describe the somatotropic organization of the spinocerebellum in the posterior and anterior lobes
Ant (sup > inf): leg> arm> head
Post (sup > inf): head >arm>leg
Cerebellar outputs travel through
Dorsal cerebellar nuclei (dentate, emboliform, globose, and fastigial)
Vestibular nu
What are the deep cerebellar nu
Dentate
Emboliform
Globose
Fastigial
What cerebellar outputs go through the dentate
Receive projections from lateral cerebellar hemispheres (interposed nu)
The _________ and ___________ nuclei receive projections from intermediate cerebellar hemispheres
Emboliform
Globose
Fastigial nu receives projections from
Vermis and part of flocculonodular node
Vestibular nu. Receive projections from
Inferior vermis and majority of flocculonodular node
Damage to the cerebellum typically has ________ effects
Ipsilateral
Dentate fibers travel through what tract?
Cerebrocerebellum
Function of the cerebrocerebellum tract
Motor planning and motor initiation of limbs
Go through the 2 paths of the cerebrocerebellar tract
Lateral hemispheres >dentate nu > contralateral red nu via SCP > inferior Oliver’s nu via central tegmental tract > renter cerebellum via Olivocerebellar fibers (decussate again and terminate through lat hemisphere cortex)
Lateral hemispheres > dentate nu > contralateral VL nu of thalamus via SCP> PriMC, PreMC, SMA, and parietal lobe
Cerebrocerebellum tract eventually ends up at the motor cortex and association cortices then send descending drive via the…..
Corticospinal tract
The spinocerebellum (vermis) tract has what function
Motor for posture, proximal limb movement, and eye movement
Go through the spinocerebellum (vermis) tract
Fibers from vermis travel to the fastigial nu > ICP down to bilateral vestibular nu and reticular formation > reticulospinal and vestibulospinal tract
Vermis> fastigial nu > SCP > contralateral sup colliculus (tectospinal tract) >PriMC, PreMC, SMA, and parietal lobe > anterior corticospinal tract
What tract eventually provides input to the reticulospinal and vestibulospinal tract, tectospinal tract and anterior corticospinal tract
Vermis Spinocerebellum
What is the function of the Spinocerebellum tract from the intermediate zone
Integrates input from appendicular limb position and somatosensory input
The spinocerebellar (intermediate zone) tract eventually sends info to what tracts
Rubrospinal and lateral corticospinal tract
Go through steps of the spinocerebellar (intermediate zone)
intermediate zone >interposed nu > SCP >contra red nu> rubrospinal tract
Intermediate zone >interposed nu > SCP > contra VL of thalamus > PriMC, PreMC, SMA, and parietal lobes > lat corticospinal tract
The vestibulocerebellum tract starts where
Inferior vermis and flocculonodular lobe
What are the steps of the vestibulocerebellum tract
Inferior vermis and flocculonodular lobe > ICP >synapse on vestibular nu >medial longitudinal fasciculus (major eye movement pathway
What artery would impact cerebellar function the most?
AICA because it supplies all of the cerebellar peduncles
