P2 - Cerebellum Flashcards
Lateral Cerebellar Hemispheres
executive functions … verbal, working memory, muscle control, balance, goal-directed movement
- right: language
- left: visuospatial functions
Anterior Lobe
- mediates unconscious proprioception
- receives input mainly from spinal cord (DCML)
Posterior Lobe
- influences initiation, planning, and coordination of movement
- determines strength, direction, and scope of movement
- inhibition of voluntary movements (GABA)
Flocculonodular Lobe
- eye movement + body balance/equilibrium during stance and gait
- consists of flocculus + nodule
- receives input from ipsilateral vestibular nuclei
- functional name = vestibulocerebellum
Primary Fissure
divides cerebellum into anterior + posterior lobes
Vermis
- midline of cerebellum, separating it into two lateral hemispheres
- coordinates movements of central body (trunk, head, proximal limbs)
- maintains upright posutre
- functional name = spinocerebellum
lesion here can lead to truncal ataxia
Paravermal Area
- coordinates movements from distal limbs (arms, legs, fingers, toes)
- skilled volitional movements
- regulatory activity is achieved by interposed nuclei
- receives input from spinocerebellar tract from hands, feet, and distal muscles
Dentate Nucleus
- regulates fine-control of voluntary movements, cognition, and sensory functions
- motor planning prior to voluntary movements
Interposed Nuclei
- control associative learning of eye-blinking and other defensive reflexes
- coordinates agonist + antagonist muscle pairs
- composed of globose nucleus + emboliform nucleus
- globose = balance, connected to vestibular system
- emboliform = regulates precision of limb movements
Fastigial Nucleus
- maintenance of balance … interprets body motion and places it on spatial planes to estimate movement of body through space
- receives afferents from vermis
Vestibulocerebellum
- regulation of movements underlying posture and equilibrium
- receives input from vestibular nuclei + apparatus in brainstem
Spinocerebellum
- coordination of gross motor limb movements and maintenance of muscle tone
- comprises vermis, intermediate zones (paravermal area), fastigial nucleus, and interposed nuclei
- receives input from spinocerebellar tracts
- sends output to rubrospinal, vestibulospinal, reticulospinal, lateral corticopspinal, and lateral corticobrainstem tracts
Cerebrocerebellum
- planning and timing of movements, cognitive functions, motor learning
- formed by lateral hemispheres
- receives input from cerebral cortex
- sends output to thalamus and red nucleus
Tonsils
inferior part of posterior lobe
Arbor Vitae
white matter
Folia of Cerebellar Cortex
gray matter
4th Ventricle
- helps form central canal for CSF flow
- protects brain from trauma (cushioning effect)
Midbrain Tectum
posterior region of midbrain containing pretectal area + colliculi
Superior Cerebellar Peduncle
- connects midbrain to cerebellum
- almost exclusively efferent
- carries efferents from globose, emboliform, and dentate nuclei to red nucleus and ventrolateral thalamus for regulation of rubrospinal + corticospinal tracts
- afferents from anterior spinocerebellar tracts
Middle Cerebellar Peduncle
- connects pons to cerebellum
- only afferent
- carries afferents from pontine nuclei
Inferior Cerebellar Peduncle
- connects medulla to cerebellum
- both afferent + efferent
- afferents from spinal cord, vestibular appartus + nuclei, and inferior olivary nucleus
- efferents to vestibular nuclei and reticular formation (vestibulospinal + reticulospinal tracts)
Which branch(es) of the vertebral artery supplies the cerebellum?
PICA
Which branch(es) of the basilar artery supplies the cerebellum?
AICA, SCA
Which tracts travel through the superior cerebellar peduncle?
anterior spinocerebellar, rostral spinocerebellar
Which tracts travel through the middle cerebellar peduncle?
corticopontocerebellar pathway
Which tracts travel through the inferior cerebellar peduncle?
cuneocerebellar, posterior spinocerebellar, rostral spinocerebellar
Posterior Spinocerebellar Tract
proprioceptive information from LE + lower trunk
ipsilateral
Anterior Spinocerebellar Tract
proprioceptive information from both sides of body
decussates twice
Rostral Spinocerebellar Tract
proprioceptive information from cervical spinal cord + T1
ipsilateral
Cuneocerebellar Tract
proprioceptive information from neck, UE, and upper back
ipsilateral
Vestibulocerebellar Output
lateral + medial vestibulospinal
Spinocerebellar Output
lateral + medial vestibulospinal, medial reticulospinal, medial corticospinal
Cerebrospinal Output
lateral corticospinal, rubrospinal
