Lecture 8

Question 1

decussation

Answer 1

crossing midline

Question 2

rostral

Answer 2

relating to, or being near the head of the body. interchangeable with superior if a human is standing upright

Question 3

caudal

Answer 3

relating to, or being near the tail or posterior part of the body

Question 4

CN 1 and 2

Answer 4

do not emerge from brainstem

Question 5

CN 3-12

Answer 5

emerge from brainstem

Question 6

CN 3 and 4

Answer 6

emerge from midbrain

Question 7

CN 5,6,7 and 8

Answer 7

emerge from pons

Question 8

CN 9,10,11 and 12

Answer 8

emerge from medulla

Question 9

three horizontal regions of brainstem

Answer 9

midbrain, pons, medulla

Question 10

external midbrain structures

Answer 10

CN 3 and 4
cerebral peduncles - descending motor tracts
superior colliculus - sub cortical visual reflexes
inferior colliculus - sub cortical auditory reflexes

Question 11

internal midbrain structures

Answer 11

cerebral aqueduct
periaqueductal gray area (PAG)
nuclei for CN 3 and CN 4
red nucleus
substantia nigra
descending motor tracts in the cerebral peduncles

Question 12

pons structures

Answer 12

CN 5-8
motor tracts that descend in the anterior pons
4th ventricle

Question 13

medulla structures

Answer 13

CN 9-12
pyramids - descending motor tracts
pyramidal decussation - descending motor tracts cross midline

Question 14

tectum

Answer 14

posterior column

Question 15

tegmentum

Answer 15

middle column

Question 16

basis

Answer 16

anterior column

Question 17

tectum location

Answer 17

posterior column of brainstem that is visualized primarily in midbrain
“everything posterior to cerebral aqueduct”

Question 18

tectum structures

Answer 18

superior colliculus - visual reflexes
inferior colliculus - auditory reflexes
reticular formation
ascending somatosensory tracts
nuclei of CN 3-12
descending motor tracts - originate from brainstem nuclei

Question 19

midbrain tegmentum

Answer 19

CN 3 and 4

Question 20

pons tegmentum

Answer 20

CN 5-8

Question 21

medulla tegmentum

Answer 21

CN 8-12

Question 22

basis location

Answer 22

the most anterior column of brainstem

Question 23

basis structures

Answer 23

descending motor tracts that originate from the cortex
corticospinal tract
corticobulbar tract
corticopontine tract

Question 24

reticular formation location

Answer 24

cluster of nuclei located in tegmentum throughout length of brainstem

Question 25

rostral reticular formation

Answer 25

upper pons and midbrain

Question 26

caudal reticular formation

Answer 26

lower pons and medulla

Question 27

caudel reticular formation function

Answer 27

regulates and modulates most areas of the CNS
modulate respiratory and cardiovascular nuclei of brainstem
modulate motor functions
modulate nociception (pain) pathways

Question 28

rostral reticular formation function

Answer 28

modulate consciousness (level of consciousness)
alertness
attention
awareness

Question 29

states of impaired consciousness

Answer 29

brain death
coma
vegetative state
minimal conscious state
stupor, lethargy, delirium
status epilepticus
akinetic mutism, abulia
sleep - normal and abnormal

Question 30

states that mimic impaired consciousness

Answer 30

locked in syndrome
dissociative disorders

Question 31

coma

Answer 31

remain unconscious
no meaningful response to stimuli
after 2-4 weeks coma will either “progress or digress” into different category
areas affected = severely depressed function of cortex and sub-cortical regions
reflexes expected to be intact = spinal cord reflex, brainstem reflexes

Question 32

vegetative state

Answer 32

remain unconscious
no meaningful response to stimuli
will display some sub-cortical function
areas effected = severely depressed function of cortex, partially depressed function of sub-cortical region
reflexes expected to be intact = spinal cord reflexes, brainstem reflexes, some arousal reflexes

Question 33

brain death

Answer 33

extreme irreversible form of coma
areas effected = absent function of cortex, sub-cortical, arousal system and brainstem
reflexes expected to be intact = spinal cord reflexes

Question 34

vertebral artery

Answer 34

small branches supply most of the medulla

Question 35

PICA (posterior inferior cerebellar artery)

Answer 35

supplies lateral medulla as it makes it way to the cerebellum

Question 36

basilar artery - pontine arteries

Answer 36

small branches supply most of the pons

Question 37

AICA (anterior inferior cerebellar artery)

Answer 37

branches from basilar artery and supplies small portion of the pons (lateral region of lower pons) as it makes it way to the cerebellum

Question 38

posterior cerebral artery

Answer 38

small branches supply midbrain

Question 39

Weber’s syndrome

Answer 39

blood vessel = right or left PCA
unilateral stroke of the anterior midbrain
region/structure damaged = basis of the midbrain - damages descending motor tracts, CN 3 is damaged as it exits the front of the midbrain
clinical findings = contralateral hemiplegia/paresis, ipsilateral CN III palsy

Question 40

Pure motor hemiparesis (PMH)

Answer 40

blood vessel = right or left pontine arteries of basilar artery along the right or left anterior pons
unilateral stroke of the anterior pons
region/structure damaged = bases of the pons - damages descending motor tracts
clinical findings = contralateral hemiplegia/paresis

Question 41

Locked-in syndrome

Answer 41

blood vessel = basilar artery
bilateral stroke of the anterior pons
region/structure damaged = basis of upper pons - damages right and left descending motor tracts
clinical findings = quadriplegia with intact sensation and cognition

Question 42

Wallenberg Syndrome (lateral medullary syndrome)

Answer 42

most common brainstem stroke
blood vessel = vertebral artery, PICA or small branches of PICA
unilateral stroke of the lateral medulla
region/structure damaged = lateral medulla and may also involve inferior cerebellum
clinical findings = loss of pain/temp to: face - ipsilateral, body - contralateral