practical 4 cranial nerves W4

Question 1

which cranial nerves are attached directly to the brain?

Answer 1

1, 2

Question 2

which cranial nerves are attached directly to the midbrain?

Answer 2

3, 4

Question 3

which cranial nerves are attached directly to the pons?

Answer 3

5

Question 4

which cranial nerves are attached directly to the pontomedullary junction?

Answer 4

6

Question 5

which cranial nerves are attached directly to the medulla?

Answer 5

7, 8, 9, 10, 11, 12

Question 6

locations of foramen rotundum/ovale/spinosum/lacerum?

Answer 6

rotundum: by sup orb fis. more anterior than others.

medial to lateral is lacerum, ovale, spinosum.

Question 7

sensory nuclei in brainstem? locations?

Answer 7

trigeminal sensory nucleus: middle cerebellar peduncle

vestibular and cochlear nuclei: below middle cerebellar peduncle

nucleus solitarius: medial medulla

Question 8

motor nuclei in midbrain? locations?

Answer 8

caudal to rostral (all quite medial)
Edinger-Westphal nucleus
oculomotor nucleus
trochlear nucleus

Question 9

motor nuclei in pons? locations

Answer 9

trigeminal motor nucleus (superior, lateral)
abducens nucleus (middle, medial)
facial motor nucleus (inferior, lateral)
superior and inferior salivatory nuclei (inferior, medial)

Question 10

motor nuclei in medulla? locations

Answer 10

from medial to lateral:
hypoglossal nucleus
dorsal motor nucleus of the vagus
nucleus ambiguus

Question 11

most common causes of lower motor neuron palsy of the facial nerve?

Answer 11

Bell’s palsy
idiopathic palsy (unilateral)

Question 12

innervation of masseter?

Answer 12

mandibular nerve (trigeminal)

Question 13

innervation of trapezius?

Answer 13

accessory nerve

Question 14

innervation of intrinsic muscles of the tongue?

Answer 14

hypoglossal nerve

Question 15

innervation of superior pharyngeal constrictor?

Answer 15

vagus nerve

Question 16

innervation of orbicularis oris?

Answer 16

facial nerve

Question 17

innervation of levator palpebrae superioris?

Answer 17

oculomotor nerve

Question 18

6 extrinsic eye muscles that move the eyeball?

Answer 18

inferior oblique
lateral rectus
medial rectus
inferior rectus
superior oblique
superior rectus

Question 19

superior oblique - innervation and action?

Answer 19

CNIV (trochlear)
depression, abduction, intorsion (inward rotational movement)
‘down and out’

Question 20

inferior oblique - innervation and action?

Answer 20

CNIII (oculomotor)
elevation, abduction, extorsion (outward rotational movement)
‘up and out’

Question 21

superior rectus - innervation and action?

Answer 21

CNIII (oculomotor)
elevation, adduction

Question 22

inferior rectus - innervation and action?

Answer 22

CNIII (oculomotor)
depression, adduction

Question 23

medial rectus - innervation and action?

Answer 23

CNIII (oculomotor)
adduction

Question 24

lateral rectus - innervation and action?

Answer 24

CNVI (abducens)
abduction

Question 25

clinical effect of CNVI (abducens) palsy? which muscles are affected?

Answer 25

diplopia when looking to the side ipsilateral to the palsy. affected muscle = lateral rectus

Question 26

clinical effect of CNIV (trochlear) palsy? which muscles are affected?

Answer 26

vertical diplopia, particularly noticeable on down gaze affected muscle = superior oblique

Question 27

clinical effect of CNIII (oculomotor) palsy? which muscles are affected?

Answer 27

ptosis (drooping of upper eyelid). when attempting to stare straight ahead, the eye looks down. muscles affected = levator palpabrae superioris, inferior and medial rectus, inferior oblique | not in worksheet but surely also the superior rectus?

Question 28

which cranial nerve makes up the afferent limb of the gag reflex?

Answer 28

glossopharyngeal nerve

Question 29

course of the trigeminal nerve? (and its branches?)

Answer 29

maxillary nerve -> foramen rotundum ophthalmic nerve -> superior orbital fissure mandibular nerve -> foramen ovale ->>> trigeminal ganglion -> trigeminal sensory nucleus -> thalamus -> internal capsule -> cortex

Question 30

which four cranial nerves carry autonomic innervation?

Answer 30

3, 7, 9, 10 III - oculomotor nerve VII - facial nerve IX - glossopharyngeal nerve X - vagus nerve

Question 31

which tissues does CNIII provide parasympathetic innervation? what is the function of this?

Answer 31

sphincter pupillae - constricts pupil ciliary muscles - contraction to shorten lens and focus on short range objects

Question 32

which tissues does CNVII provide parasympathetic innervation? what is the function of this?

Answer 32

mucosa of the oral/nasal cavities and pharynx - produce mucous lacrimal gland - produce tears submandibular and sublingual glands - produce saliva

Question 33

which tissues does CNIX provide parasympathetic innervation? what is the function of this?

Answer 33

parotid gland - produce saliva

Question 34

which tissues does CNX provide parasympathetic innervation? what is the function of this?

Answer 34

heart - reduce resting heart rate GI organs - smooth muscle contraction and secretion of digestive juices