Cerebellum

Question 1

What is the cerebellum?

Answer 1

“little brain”. brain structure located in brainstem

Question 2

What is one of the primary functions of the cerebellum?

Answer 2

to detect the difference or motor error between an intended movement and the actual movement to reduce the error

Question 3

How does the cerebellum influence movement and balance?

Answer 3

by modifying the activity patterns of the upper and lower motor neurons

Question 4

What are the two cerebellar hemispheres?

Answer 4

two; anterior and posterior lobe

Question 5

What are the deep cerebellar nuclei?

Answer 5

clusters of cells in nuclei buried deep in the white matter of the cerebellum

Question 6

What are the three cerebellar peduncles?

Answer 6

Superior, middle and inferior

Question 7

Cerebellar hemispheres can be divided into what three parts?

Answer 7

cerebrocerebellum (lateral zone)
spinocerebellum (median zone)
Vestibulocerebellum (caudal-inferior zone, oldest part of cerebellum)

Question 8

What is the spinocerebellum composed of?

Answer 8

Vermis (most median zone)
Paramedian zone

Question 9

What is the vestibulocerebellum composed of?

Answer 9

flocculus and nodulus

Question 10

The cerebrocerebellum receives input from what?

Answer 10

indirect input from many areas of the cerebral cortex

Question 11

What are the functions of the cerebrocerebellum?

Answer 11

planning, coordination and execution of complex spatial and temporal sequences of movement, cognitive functions like timing, attention, etc

Question 12

The spinocerebellum receives input from what?

Answer 12

direct input from the spinal cord (proprioceptive info)

Question 13

What is the vermis involved with?

Answer 13

movement of the proximal muscles, movement of eyes

Question 14

What is the paramedian zone involved with?

Answer 14

movement of distal muscles (arm and leg muscles

Question 15

The vestibulocerebellum receives input from what?

Answer 15

from the vestibular nuclei in the brainstem

Question 16

What are the functions of the vestibulocerebellum?

Answer 16

involved in regulation of movements that maintain posture, balance, equilibrium

Question 17

What are the connections between the cerebellum and other parts of the nervous system made by?

Answer 17

made by the three large pathways called the cerebellar peduncles

Question 18

What is the superior cerebellar peduncle?

Answer 18

mainly efferent pathways (output)

Question 19

What is the middle cerebellar peduncle?

Answer 19

afferent pathways (input)

Question 20

What is the inferior cerebellar peduncle?

Answer 20

Multiple pathways (afferent and efferent)

Question 21

What does the corticopontocerebellar pathway do?

Answer 21

transmits info from motor, premotor cortex, somatosensory cortex via the pontine nuclei. Pathway enters the cerebellum through the middle cerebellar peduncle (fibers decussate).
Projects mostly to the cerebrocerebellum

Question 22

What is the spinocerebellar pathway?

Answer 22

Transmit info from periphery via the spinal cord nuclei ==> projects to spinocerebellum ==> fibers enter cerebellum through the inferior cerebellar peduncle (do not decussate)

Question 23

What information does the spinocerebellar pathway provide the cerebellum?

Answer 23

informs cerebellum of the momentary status of muscle contraction, tension, limb position and motion of the body

Question 24

What is the vestibulocerebellar pathway?

Answer 24

transmit info from the vestibular pathway ==> projects to the vestibulocerebellum ==> fibers enter cerebellum through the inferior cerebellar peduncle (do not decussate)

Question 25

What is the olivocerebellar pathway?

Answer 25

transmit info from cortex via red nucleus and inferior olive nucleus==> projects to cerebrocerebellum and deep nuclei ==> fibers enter cerebellum through inferior cerebellar peduncle (fibers decussate)

Question 26

What do the inputs from the olivocerebellar pathway participate in?

Answer 26

Participate in the learning and memory functions served by cerebellar circuitry

Question 27

What do the cerebellar cortex neuron project to?

Answer 27

project to the deep cerebellar nuclei

Question 28

What do the deep cerebellar nuclei project to?

Answer 28

project out of cerebellum through the superior cerebellar peduncle into the primary motor & premotor cortex and towards the superior colliculus

Question 29

What does the primary motor & premotor cortex participate in?

Answer 29

participates in planning and initiating voluntary movements

Question 30

What does the superior colliculus do?

Answer 30

modulates the activity of the upper motor neurons concerned with eye movement

Question 31

What does the cerebellum send its outputs into the vestibular nucleus through?

Answer 31

through the inferior cerebellar peduncle

Question 32

What does the cerebellar-vestibular pathway allows the cerebellum to do?

Answer 32

to influence posture and equilibrium

Question 33

Purkinje cells in the cerebellum receive what?

Answer 33

Receive sensory info from the inferior olive and pontine nuclei through the mossy fibers and climbing fibers

Question 34

What do the purkinje cells do with the info they receive in the cerebellum?

Answer 34

process the info and compare the status of ongoing movement

Question 35

What do the purkinje cells output after receiving info in the cerebellum?

Answer 35

send inhibitory projection onto the deep cerebellar nuclear cells ==> deep cerebellar nuclei send excitatory efferent onto motor cortex via the thalamus ==> cerebellar neurons output to the motor cortex generates an error correction signal to modify movement

Question 36

What happens to purkinje cells and deep cerebellar nuclei cells when the wrist is at rest and when it is moving?

Answer 36

at rest: both are tonically active
During movement: both cell types receive a transient inhibition that blocks their tonic activity

Question 37

What higher functions does the cerebellum have?

Answer 37

has a role in:
sensory acquisition
motor attention
timing of motor action
prediction and preparation of movement
motor sequence learning and memory

Question 38

The cerebellum is considered a helper structure, what does it help with?

Answer 38

circuitry could be acting as a predictor and adjusts the body movements accordingly. It helps coordinate motor actions unconsciously