Lesson 7 - The Cerebellum Flashcards
The cerebellum is ? gms, ?/10 of adult brain
150 gms, 1/10 of adult brain
The cerebellum is bilaterally ————- with an extensive cortex: ½ that of
cerebral cortex and with 3.6 x the number of neurons
symmetrical
The cerebellum is located in ———— ————— ———
* ———— ———— (cerebrum), 4th ventricle (brainstem)
posterior cranial fossa
tentorium cerebelli
The cerebellum communicates with brainstem via superior , middle, and inferior ——– —————s
cerebellar peduncles
The cerebellum functions in:
* gait and ————–
* ————- of movements
* precision and accuracy of movement
* ———- learning
* reflex modification
balance
coordination
motor
Longitudinal divisions of the cerebellum
- Vermis
– ———— region
– ————- Hemispheres
Paravermal
Cerebellar
Transverse divisions of the cerebellum:
Anterior lobe
* ————– fissure– Posterior (or Middle) lobe
* Posterolateral fissure– —————- lobe
Primary
Flocculonodular
————– peduncle –sup pons/ midbrain
———— peduncle –pons
————– peduncle -medull
Superior
Middle
Inferior
Superior cerebellar peduncle –sup pons/ midbrain
* ————– projections
Efferent
Middle peduncle –pons
* ————— projections
Afferent
Inferior peduncle –medulla
* ———- and ———— projections
afferent and efferent
Cerebellum Lobules:
The lobule just rostral of the 4th ventricle is I and the one just caudal to it is X
Between lobules V and VI is the primary fissure and separates the posterior lobe from the
anterior lobe
The tonsils are clinically important due to their proximity to the ————— ————–
reticular formation
Cerebellar Nuclei:
4 nuclei:
Lateral –> Medial
– Dentate
* ————– Hemisphere
– Emboliform (Interposed
nuclei)
* ————– zone
– Globose (Interposed
nuclei)
* ————- zone
– Fastigial
* ————
Cerebellar
Paramedian
Paramedian
Vermis
What are the 3 Cerebellar cortex layers?
1) Molecular– 2) Purkinje– 3) Granule
What are the 5 cell types of the cerebellar cortex?
5 cell types:
Purkinje ([ ([–], Efferents)
Granule ([+], target of Mossy)
Stellate ([ ([–], inhibit nearby Purkinje)
Basket ([ ([–], inhibit distant Purkinje)
Golgi ([ ([–], inhibit Granule cells)
Name 2 fibres of the cerebellar cortex
2 fibers
– Mossy fiber ([+], Afferents from cortex, brainstem trigeminal nerve, vestibular nerve and nuclei, reticular
nuclei and spinal cord cuneate and gracile)
– Climbing fiber ([+], Afferents, only from inferior olive)
Functional divisions of the cerebellum:
– AKA Archicerebellum
– Regulates balance and reflex eye movements
– AKA Paleocerebellum
– Adjust ongoing movements and controls muscle tone
– Stance and gait
– AKA Neocerebellum
– Planning and initiation of skilled movements, smooth and
precise control
Vestibulocerebellum
Spinocerebellum
Cerebrocerebellum
Circuitry:
projections to the cerebellum:
Input from the frontal and parietal cortices is relayed to the pons (i.e. pontocerebellar tract), and thereafter to the
———— ————— via the middle cerebellar ————
Sensory input from the vestibular and reticular nuclei, inferior olives and the dorsal nuclei of Clark is relayed to
the cerebellar cortex via the inferior cerebellar ————s
cerebellar cortex
peduncle
peduncles
Circuitry:
projections from the cerebellum:
Information sent to the ———- nuclei exits
the cerebellum via the ———- —————–
peduncle and is relayed to the vestibular
nuclei
Information sent to the globes, ———– and ————– nuclei exits the cerebellum via
the superior cerebellar peduncle and is
relayed to the thalamus and the motor cortex
fastigial
inferior cerebellar
emboliform and dentate
The Somatotopy of the ————— is not as clearly organized and orderly as that in motor and somatosensory cortex,
but does exist
Spinocerebellum
The superior cerebellar peduncle is the primary ———- pathway from the deep cerebellar
nuclei
OUTPUT
The middle cerebellar peduncle is an ———- pathway from the cerebral cortex
INPUT
The inferior cerebellar peduncle provides —————- from the spinal cord, brainstem and inferior olive AND ——– to the brainstem
input
output
Outputs travel via superior and inferior peduncles to terminate in 4 mains structures that
send tracts down the spinal cord to influence spinal motor neurons:
1. Motor regions of cerebral cortex (via thalamus relay)
2. —– nucleus
3. ————- nuclei
4. ————- nuclei
Red
Vestibular
Reticular
