Cranial Nerve Motor Nuclei

Question 1

corticonuclear projections to

Answer 1

1. trigeminal
2. facial
3. flossopharyngeal
4. vagus
5. accessory
6. hypoglossal

Question 2

cortical projections to

Answer 2

1. oculomotor
2. trochlear
3. abducent

Question 3

areas that contribute to corticonuclear

Answer 3

1. premotor cortical
2. primary motor cortex
3. primary sensory cortex

Question 4

layer of cortex that gives corticonuclear

Answer 4

internal pyramidal (V) has pyramidal cells that give rise to corticonuclear tract
-pyramidal cells are cell bodies of UMNs

Question 5

nuclei in pons

Answer 5

trigeminal motor (V)
facial motor (VII)

Question 6

nuclei in medulla

Answer 6

nucleus ambiguus (IX, X)
hypoglossal (XII)

Question 7

nuclei in spinal cord

Answer 7

accessory (XI)

Question 8

corticonuclear tract path

Answer 8

1. cortex
2. genu of internal capsule
3. posterior limb of internal capsule

Question 9

blood supply to internal capsule

Answer 9

lenticulostriate arteries from middle cerebral supply internal capsule

Question 10

trigeminal nucleus synapse

Answer 10

bilateral corticonuc projections synapse in RF interneurons and trigeminal motor nucleus

Question 11

facial nucelus synapse

Answer 11

upper half of facial nucleus = recieves bilateral UMN corticonuc projections
lower half = only contralateral UMN corticonuc projections

all in lower/caudal pons

Question 12

facial nucleus lesion

Answer 12

upper half of the facial nucleus has back up since bi lateral
-if lesion in one side then still have stimulation from other side

if lower half lesion then contralat motor deficit, no back up

Question 13

blood supply to facial nucleus

Answer 13

anterior inferior cerebellar +
basilar

Question 14

nucleus ambiguus innervates what

Answer 14

glossopharyngeal and vagus

-muscles of soft palate, larynx, pharynx

Question 15

projections to nucleus ambiguus

Answer 15

bilateral corticonuclear but primarily contralateral

i.e. uvula deviates to side of lesion bc the contralateral muscles are not opposing

Question 16

projections to accessory nucleus

Answer 16

ipsilateral to trap and SCM

Question 17

projections to hypoglossal nucleus

Answer 17

most muscles are bilateral innervated except genioglossus muscle are contralateral

Question 18

tongue deviations

Answer 18

UMN lesion = deviate away from side of lesion (towards the weak side bc pushed by intact muscles)

LMN lesion = deviate towards side of lesion (toward weak side still)

lesion of hypoglossal

Question 19

eye fields

Answer 19

frontal and parietal eye fields have cell bodies that project to midbrain and pons RF to control eye movement (oculomotor, trochlear, abducent) contralateral