Somatosensory pathways to the cerebellum

Question 1

Is the cerebellum intimately involved with unconscious or conscious coordination of skeletal muscle of maintaining posture, locomotion and other motor activities?

Answer 1

Unconscious control

Question 2

What types of input information of the nervous system are required in the cerebellum?

Answer 2

General somatosensory and proprioceptive

Question 3

What are the pathways of the lower body for proprioception?

Answer 3

Dorsal spinocerebellar tract

Ventral spinocerebellar tract

Question 4

Trace the movement of proprioception from the lower body via the dorsal spinocerebellar tract to the cerebellum

Answer 4

Fasciculus Gracillis -> nucleus dorsalis -> dorsal spinocerebellar tract -> inferior cerebellar peduncle

Question 5

What does the dorsal spinocerebellar tract do? and from which side?

Answer 5

Relays proprioception information from the trunk and lower extremities of the ipsilateral side of the body

Question 6

What is the ventral spincerebellar tract?

Answer 6

alternative pathway from the lower body to the cerebellum

Question 7

Where are the second order neurons of the ventral spincerebellar tract found?

Answer 7

In the spinal cord gray

Question 8

Do the second order axons of the ventral spincerebellar tract decussate?

Answer 8

Yes, to form the ventral spincerebellar tract

Question 9

Where do ventral spincerebellar tract travel?

Answer 9

Ascend through the brainstem and enters the cerebellum through the superior cerebellar peduncle

Question 10

What happens to the ventral spincerebellar tract in the medullary center of the cerebellum?

Answer 10

The ventral spincerebellar tract decussates to the opposite side of the cerebellum

Question 11

How many times does the ventral spincerebellar tract decussate?

Answer 11

Twice, once in the spinal cord and once in the cerebellum

Question 12

What fibers project to the lateral cuneate nucleus in the medulla?

Answer 12

Axon collaterals from the fasciculus cuneatus

Question 13

What makes up the cuneocerebellar tract?

Answer 13

Axons from the accessory cunteate nucleus

Question 14

What side of the cerebellum do the cuneocerebellar tracts project to and via what?

Answer 14

the cuneocerebellar tract projects to the ipsilateral side of the cerebellum through the ICP

Question 15

How do fibers from the proprioceptive pathway of the upper body project to the cerebellum?

Answer 15

1) Axon collaterals from the fasciculus cuneatus project to the lateral (accessory) cuneate nucleus in the medulla
2) axons from the accessory cuneate nucleus make up the cuneocerebellar tract and project to the ipsilateral side of the cerebellum through the ICP

Question 16

What are the 3 major somatosensory/proprioceptive pathways that provide input to the cerebellum?

Answer 16

Dorsal spinocerebellar tract
Ventral spincerebellar tract
cuneocerebellar tract

Question 17

Of the 3 major somatosensory/proprioceptive pathways that provide input to the cerebellum which are upper and which are lower body?

Answer 17

Lower body:Dorsal spinocerebellar tract
Ventral spincerebellar tract
Upper body: cuneocerebellar tract

Question 18

What is common between the pathways of the major somatosensory/proprioceptive pathways? (hint: think of which side of body and cerebellum)

Answer 18

The pathways all provide input from one side of the body to the ipsilateral side of the cerebellum