cerebellum

what does cerebellum mean?

little brain

why is it called the cerebellum?

looks like a smaller version of the cerebrum

what is the main function of the cerebellum?

coordinates and adjusts voluntary movement

what does the functions of the cerebellum involve? (4)

- posture

- balance

- maintenance of muscle tone

- coordinated skilled voluntary motor activities (e.g. riding a bike)

what structures are the cerebellum in contact with?

- cerebral cortex

- many structures in CNS and PNS

what type of information does the cerebellum process?

information about current movement and position

which part of the cranium does the cerebellum lie?

posterior cranial fossa

what is the cerebellum covered by?

tentorium cerebelli

what does the tentorium cerebelli do?

separates cerebellum from occipital and temporal lobes of the brain

what lies anteriorly to the cerebellum?

- 4th ventricle

- pons

- medulla oblongata

what is the cerebellum made up of?

2 hemispheres

what are the 2 hemispheres connected by?

vermis

what structures lie inferiorly to the vermis?

cerebellar tonsils (2 distinguishable lobules)

what matter is the cerebellum made up of?

grey and white matter

where is the grey matter located?

tightly folded on the surface of the cerebellum

what does the tightly folded grey matter form?

cerebellar cortex

where is the white matter located?

underneath the cerebellar cortex

what are the 3 anatomical lobes of the cerebellum?

- anterior

- posterior

- flocculonodular

what are the 3 zones of the cerebellum?

- midline or vermis

- intermediate zone

- lateral hemispheres

what are the 3 functional regions of the cerebellum?

- cerebrocerebellum/pontocerebellum

- spinocerebellum

- vestibulocerebellum

where is the cerebrocerebellum/pontocerebellum located?

lateral hemispheres

what is the function of the cerebrocerebellum/pontocerebellum? (3)

- receives inputs from cerebral cortex and pontine nuclei

- sends outputs to thalamus and red nuclei

- regulates coordination of muscle activation

where is the spinocerebellum loacted?

vermis and intermediate zones

what is the function of the spinocerebellum? (2)

- regulation of muscle tone

- adjusting movements

where is the vestibulocerebellum located?

flocculonodular lobe

what is the function of the vestibulocerebellum? (1)

maintenance of posture and balance

what separates the posterior and anterior lobes?

primary fissure

what separates the posterior and flocculonodular lobe?

posterolateral fissure

what connects the cerebellum to the brainstem?

cerebellar peduncles

what are the 3 cerebellar peduncles?

- superior

- middle

- inferior

what do the cerebellar peduncles consist of?

efferent and afferent axons between the cerebellum and CNS

what does the superior cerebellar peduncle connect to?

midbrain

what does the middle cerebellar peduncle connect to?

pons

what does the inferior cerebellar peduncle connect to?

medulla

what test in a neuro exam would indicate balance problems, so potentially cerebellar problems?

Romberg's

what is Romberg's test?

1) pt stands still with feet together to test balance

2) pt is then asked to close eyes

what would a positive romberg's sign be?

sway or fall when eyes are closed

what could a positive romberg's sign indicate?

cerebellar, vestibulocochlear nerve, visual or proprioceptive dysfunction

what input does the cerebellum need to receive in order to have coordination?

- visual input

- proprioceptive input

- vestibulocochlear input

what could it indicate if someone was falling with their eyes open?

cerebellar dysfunction

what could it indicate if someone fell only with their eyes closed?

proprioceptive or vestibulocochlear dysfunction