Lecture 20: Cranial Nerves - B

Question 1

_____: Organ made of nerve fibers (+ connective tissue) that connects CNS to periphery (muscles, glands, skin)

Answer 1

Nerve

Question 2

How many spinal nerves serve the body? cranial?

Answer 2

31 spinal nerves (body)
12 cranial nerves (head and neck)

Question 3

The vagus nerve also supplies the ___ and ___

Answer 3

thorax and abdomen

Question 4

Most cranial nerve nuclei receive ___ innervation from the cortex
A. bilateral
B. unilateral

Answer 4

A. bilateral

Question 5

True or False: If one has an UMN lesion, ipsilateral muscles are paralyzed. However, if one has a LMN lesion, muscle function is intact

Answer 5

False

LMN lesion = ipsilateral m paralyzed
UMN lesion = function intact

Question 6

True or False: The number of cranial nerves decreases rostral to caudal

Answer 6

False - there’s an INCREASE

Question 7

The medial cranial nerves tend to have ____ function while the lateral ones have ____ function

Answer 7

motor; sensory

Question 8

Answer 8

Question 9

Which CN’s have sensory function?

Answer 9

fdf

Question 10

Which CN’s have motor function?

Answer 10

fdds

Question 11

Which CN’s have both motor and sensory function?

Answer 11

Question 12

Which four CN’s are found in the medulla?

Answer 12

CN 9-12

Question 13

Which three CN’s are found in the pons?

Answer 13

CN 5-7

Question 14

Which two CN’s are found in the midbrain?

Answer 14

Oculomotor and Trochlear

Question 15

Which CN innervates the superior, inferior & medial rectus, inferior oblique
A. CN 3
B. CN 4
C. CN 5
D. CN 6

Answer 15

A. CN 3

Question 16

CN ___ innervates the superior oblique while CN ____ innervates the lateral rectus
A. CN 4; CN 6
B. CN 6; CN 4
C. CN 2; CN 6

Answer 16

A. CN 4; CN 6

Question 17

True or False: CN 3 adducts and abduccts

Answer 17

True

Question 18

True or False: CN IV is important for intorsion of superior oblique while CN III is important for extorsion of inferior oblique

Answer 18

True

Question 19

Where are the oculomotor nerve and the Edinger-Westphal nucleus located?
A. medulla
B. midbrain
C. pons

Answer 19

B. midbrain

Question 20

Which CN mediates conscious eye
movements and reflexes?

Answer 20

Oculomotor nerve

Question 21

Which 2 structures are innervated by the oculomotor nerve??

Answer 21

extraocular muscles &
levator palpebrae superioris

Question 22

Which two structures does the Edinger-Westphal nucleus innervate?

Answer 22

pupillary sphincter &
ciliary muscle

Question 23

What are the effects of a lesion on the oculomotor nerve or the Edinger-Westphal nucleus?

Answer 23

1) Ipsilateral ptosis
2) mydriasis
3) lateral strabismus

Question 24

Which CN causes depression &
intorsion of the eye + has a nucleus located in the midbrain?

Answer 24

Trochlear nerve

Question 25

Which CN is the smallest and only one nerve to exit via: dorsal surface?

Answer 25

Trochlear Nerve

Question 26

Which cranial nerve innervates contralateral superior oblique muscle? A. Trochlear Nerve B. Abducens Nerve C. Oculomotor Nerve D. Trigeminal Nerve

Answer 26

A. Trochlear Nerve

Question 27

Which CN mediates lateral eye movements? A. Trochlear Nerve B. Abducens Nerve C. Oculomotor Nerve D. Trigeminal Nerve

Answer 27

B. Abducens Nerve

Question 28

Which CN has a nucleus that is located in the pons and innervates lateral rectus muscle? A. Trochlear Nerve B. Abducens Nerve C. Oculomotor Nerve D. Trigeminal Nerve

Answer 28

B. Abducens Nerve

Question 29

True or False: CN III controls medial rectus of other eye simultaneously

Answer 29

True

Question 30

Lesion of which CN results in diplopia?

Answer 30

Abducens nerve

Question 31

Damaged left abducens nerve results in ___ strabismus and impaired ___ gaze to side of lesion

Answer 31

medial; lateral

Question 32

Which CN mediates head turning?

Answer 32

Spinal Accessory

Question 33

The Spinal Accessory is located in an unusual location -- namely: in the ...

Answer 33

upper cervical spinal cord

Question 34

Which CN innervates sternocleidomastoid to turn head to opposite side + trapezius to elevate shoulder?

Answer 34

Spinal accessory

Question 35

Which CN mediates movement of the tongue and has its nucleus in the medulla?

Answer 35

Hypoglossal nerve

Question 36

Which two structures does the hypoglossal nerve innervate?

Answer 36

Intrinsic & extrinsic tongue muscles

Question 37

Lesion of which CN nuclei results in deviation of tongue towards damaged side?

Answer 37

Damage to hypoglossal nerve

Question 38

Which CN mediates facial sensation and chewing?

Answer 38

Trigeminal

Question 39

Mesencephalic, chief & spinal trigeminal nuclei are located throughout brainstem and upper SC. What are their function?

Answer 39

Touch, pain, temperature sensation & proprioception for face

Question 40

The trigeminal motor nucleus in ___and innervates mastication muscles in ____

Answer 40

pons; (V3) mandibular division

Question 41

Lesions in which CN nuclei would result in a pronounced jaw-jerk reflex?

Answer 41

CN V

Question 42

Which CN allows one to express, taste, cry & salivate?

Answer 42

Facial nerve

Question 43

True or False: Both the facial nucleus and the superior salivatory nucleus are located in the pons

Answer 43

True

Question 44

Which of the following innervates muscles of facial expression? A. Facial nucleus B. Superior salivatory nucleus

Answer 44

A. Facial nucleus

Question 45

Which of the following provides parasympathetic innervation to lacrimal and salivary (sublingual & submandibular) glands? A. Facial nucleus B. Superior salivatory nucleus

Answer 45

B. Superior salivatory nucleus

Question 46

True or False: Aberrant regeneration of the salivary fibers that innervate the lacrimal glands can lead to “crocodile tears”

Answer 46

True

Question 47

Where are the Inferior Salivatory + Nucleus Ambiguus located?

Answer 47

Medulla

Question 48

Which CN functions in swallowing & salivation + provides sensation to posterior 1/3 of the tongue?

Answer 48

Glossopharyngeal nerve

Question 49

Nucleus ambiguus innervates the ____ while the Inferior Salivatory innervates the ____

Answer 49

stylopharyngeous muscle; Parasympathetic innervation of parotid gland

Question 50

Check integrity of ____ nerve with cotton swab to test pharyngeal (gag) reflex

Answer 50

Glossopharyngeal

Question 51

____ is cranial nerve that is the major parasympathetic line + provides sensory info from all viscera?

Answer 51

Vagus nerve

Question 52

Nucleus ambiguus (medulla) and Dorsal Motor Nucleus (medulla) are associated with which CN? Innervation?

Answer 52

Vagus Nucleus ambiguus: Innervates pharyngeal & laryngeal mu Dorsal Motor Nucleus: smooth muscles & glands of abdominal/thoracic cavities

Question 53

Unilateral lesion of vagus produces ____ ____of soft palate and uvula deviation to intact side

Answer 53

ipsilateral plegia