Brainstem and cranial nerves 1

Question 1

what are 3 portions of brainstem

Answer 1

1. midbrain
2. pons
3. medulla

Question 2

what are diffs. b/w grey matter in brainstem vs. cord (3)

Answer 2

1. in cord is continuous, but the stem has functionally specialized nuclei
2. brainstem serve special sense: hearing, balance, taste
3. contains reticular formation: maintains vital functions and level of arousal

Question 3

what are 2 decscending white matter tracts in the stem

Answer 3

1. voluntary motor (corticospinal, corticobulbar)

2. involuntary motor

Question 4

what does involuntary motor control

Answer 4

1. posture
2. muscle tone
3. autonomic functions

Question 5

what are 2 main ascending white matter tracts in brainstem

Answer 5

1. STT and DC for conscious somatosensation

2. from cord to cerebellum - for proprioception to coordinate movement

Question 6

what are 2 main white matter surface features in brain stem

Answer 6

1. peduncles - connect midbrain to cerebral hemispheres

2. pyramids

Question 7

what are 3 cerebellar peduncles and what do they connect?

Answer 7

1. superior - midbrain to cerebellum
2. middle - pons to cerebellum
3. inferior - medulla to cerebellum

Question 8

what are 2 ways a tumor can impinge on the brainstem

Answer 8

1. extramedullary - eg tumor from outside

2. intramedullary - tumor stroke from inside

Question 9

what does the timeline tell you about a lesion

Answer 9

fast -stroke

slow - tumor