Cerebellum Worksheet - Lecture 9

Question 1

where is the cerebellum located

Answer 1

dorsally to the pons and medulla

in the posterior cranial fossa

Question 2

what separates the CB from the occipital and temporal lobes

Answer 2

tentorium cerebelli

Question 3

what would happen if the Cb was compressed or pushed downward

Answer 3

add pressure to the pons, medulla and SC

Question 4

where does the cerebellum receive its blood supply

Answer 4

vertebrobasilar system

–> posterior inferior cerebral artery (PICA)

–> anterior inferior cerebral artery (AICA)

–> superior cerebral artery (SCA)

Question 5

what are the 3 ways to divide the Cb

Answer 5

zones

lobes

fxn

Question 6

zones

Answer 6

vermal (median) zone

paravermal (intermediate) zone

hemispheric (lateral) zone

Question 7

lobes

Answer 7

anterior

posterior

flocculonodular

Question 8

how are the lobes connected to the rest of the brain

Answer 8

3 dense fiber bundles
–> peduncles

Question 9

fxn

Answer 9

vestibulocerebellum

spinocerebellum

cerebrocerebellum

Question 10

vestibulocerebellum role

Answer 10

maintenance of balance

control of eye movements

Question 11

spinecerebellum role

Answer 11

regulation of muscle tone

coordination of skilled voluntary movement

Question 12

cerebrocerebellum role

Answer 12

planning and modulation of voluntary activity

storage of procedural memories

Question 13

three layers of the Cb cortex

Answer 13

molecular (outermost)

purkinje (middle layer)

granular (innermost)

Question 14

molecular layer

Answer 14

contains 2 primary interneurons
–>inhibitory in nature

both help to communicate with purkinje cell dendrites via GABAergic synapses

Question 15

2 primary interneurons of the molecular layer

Answer 15

stellate cells

basket cells

Question 16

purkinje layer contains

Answer 16

cells with some of the largest neurons in the human brain

Question 17

how are purkinje fibers arranged

Answer 17

stacked one in front of the other

domino like

Question 18

purkinje cells communicate

Answer 18

with deep cerebellar nuclei

Question 19

granular layer

Answer 19

mossy fibers enter the granular layer from the pontine nuclei

Question 20

what are formed in the granular layer

Answer 20

excitatory synapses with granule cells and cells of the deep cerebellar nuclei

Question 21

how many synapses are created –> granular layer

Answer 21

hundred to thousands w/ purkinje cell dendrites

Question 22

deep cerebellar nuclei

Answer 22

fastigial, glubose, emboliform, dentate

involved in influencing the descending motor pathways and the motor neurons of the brain stem and SC

Question 23

what are the deep cerebellar nuclei the main source of

Answer 23

cerebellar output

receive collaterals of cerebellar afferents and purkinje cell axon terminals from the overlying cerebellar cortex

Question 24

fastigal nucleus location

Answer 24

roof of the 4th ventricle

Question 25

what does the fastigal nucleus receive

Answer 25

fibers arising from the vestibulocerebellum and first order collaterals form the vestibular apparatus

Question 26

where do outputs from the fastigal nucleus go

Answer 26

lateral and inferior vestibular nuclei influence the vestibulospinal tracts

Question 27

what does the fastigal nucleus play a larger role in

Answer 27

balance eye fxn vestibulospinal reflex

Question 28

globuse and emboliform nuclei

Answer 28

together referred to as the interposed nuclei

Question 29

afferents to interposed nuclei

Answer 29

purkinje cell terminals arising from the spinocerebellum

Question 30

where do the interpose nuclei project to

Answer 30

red nucleus rubrospinal tract

Question 31

what do the interpose nuclei project via

Answer 31

ventral lateral nucleus of thalamus lateral corticospinal tract

Question 32

denate nucleus

Answer 32

largest of the cerebellar nuclei tooth shaped

Question 33

where does the denate nucleus receive inputs from

Answer 33

collaterals of pontocerebellar afferents purkinje cell terminals originating from the cerebrocerebellar

Question 34

where does output from the denate nucleus go

Answer 34

premotor and primary motor cortexes via ventral lateral nucleus of the thalamus

Question 35

what do the outputs of the denate nucleus do

Answer 35

influence upcoming motor activity thats about to occur final determinant of movement

Question 36

what else does the denate nucleus participate in

Answer 36

vestibulo-oculomotor pathways

Question 37

what does the Cb receive while initiating movement

Answer 37

efference copy of movement from the frontal and parietal cerebral motor cortices via the relay pons

Question 38

what does the efference copy of movement give the Cb

Answer 38

info to compare with the motion feedback it gets from the body

Question 39

what is the Cb enabled to do --> movement

Answer 39

compare performed movement to the desired movement

Question 40

what can the Cb compare

Answer 40

current movement with the movement performed in the past in order to make changes and modify the movements to be most effective

Question 41

what does the Cb allow

Answer 41

correction of movement as it unfolds

Question 42

proprioceptive feedback of the Cb

Answer 42

tells the Cb how the body is moving

Question 43

how does the body tell the Cb how the body is moving

Answer 43

SC relays the proprioceptive info of ongoing movement and posture for to immense # of muscle spindles and other mechanoreceptors throughout the body

Question 44

what does the vestibular nuclei do during proprioceptive feedback

Answer 44

sends info on angular and linear acceleration from labyrinth in the ear

Question 45

what does the inferior olive do during proprioceptive feedback

Answer 45

active role in developing memory of the Cb in order for us to master new complex movements

Question 46

where can lesions occur

Answer 46

central, anterior and posterior lobes of Cb including the vermin (spinocerebellum)

Question 47

what do lesions result in

Answer 47

LE dyscoordination and/or deficits in LE equilibrium response