Module 4 - Cranial Nerves

Question 1

What is general somatic afferent?

Answer 1

sensory; pain, temperature, and mechanical stimuli in skin, muscle, joints

Question 2

What is special somatic afferent?

Answer 2

sensory; special senses of sight, hearing, equilibrium

Question 3

What is general visceral afferent?

Answer 3

sensory; visceral structures

Question 4

What is general somatic efferent

Answer 4

voluntary motor control

Question 5

What is special visceral afferent?

Answer 5

smell and taste

Question 6

What is general visceral efferent?

Answer 6

autonomic innervation of smooth muscle

Question 7

What is special visceral efferent?

Answer 7

same as branchial efferent - certain striated muscles muscles of the face, larynx, pharynx; identical to normal striated muscles but the neurons have distinctive location in brainstem

Question 8

Damage to UMNs results in what?

Answer 8

spasticity

Question 9

Damage to LMNs results in what?

Answer 9

paralysis/weakness

Question 10

What is CN I?

Answer 10

olfactory

Question 11

What is CN II?

Answer 11

optic nerve

Question 12

If there’s damage to CN II BEFORE the optic chiasm, what would happen?

Answer 12

would lose one eye, but have both visual fields

Question 13

If there’s damage to CN II AFTER the optic chiasm, what would happen?

Answer 13

both eyes probably intact, but one visual field is missing

Question 14

What is CN III?

Answer 14

Oculomotor; visual tracking, fixation on object, pupil adjustments, elevation of eyelid

Question 15

What is CN IV?

Answer 15

Trochlear: motor for the eye

Question 16

What is CN VI?

Answer 16

Abducens: Motor for a few eye muscles

Question 17

Where does CN V originate?

Answer 17

Pons

Question 18

What are the three branches of CN V?

Answer 18

opthalmic (sensory), maxillary (sensory), mandibular (motor and sensory)

Question 19

CN V provides motor innervation to what?

Answer 19

muscles of mastication

Question 20

LMN damage to CN V results in what ?

Answer 20

flaccid paralysis of the ipsilateral mastication muscles; jaw deviates toward affected side; jaw protrusion affected

Question 21

Bilateral UMN damage to CN V results in what?

Answer 21

severe effects characterized by restricted movements, swallowing and articulation difficulties

Question 22

Unilateral UMN damage to CN V results in what?

Answer 22

mild effects - bilateral innervation

Question 23

What are the four branches of CN VII?

Answer 23

branchial motor, visceral motor, special sensory, general sensory

Question 24

What does the branchial motor of CN VII do?

Answer 24

voluntary control of the muscles of facial expression and some suprahyoids

Question 25

What does the visceral motor branch of CN VII do?

Answer 25

secretion from submandibular, sublingual and lacrimal glands; mucous membranes of nasopharynx and hard and soft palates

Question 26

What does the special sensory branch of CN VII do?

Answer 26

taste information from anterior 2/3 of tongue and hard and soft palates

Question 27

What does the general sensory branch of CN VII do?

Answer 27

sensory information from ear

Question 28

So in general: CN VII?

Answer 28

muscles of facial expression, sensation in front of mouth, salivary glands, taste to front of tongue

Question 29

LMN damage to CN VII results in what?

Answer 29

sensory deficits; if just branchial motor branch, results in facial paralysis (bell's palsy)

Question 30

Unilateral LMN damage to CN VII results in what?

Answer 30

loss of voluntary control of lower muscles of facial expression; voluntary control of muscles of the forehead will be spared due to bilateral innervation

Question 31

Bilateral LMN damage to CN VII results in what?

Answer 31

paralysis of all upper and lower facial muscles; pseudobulbar palsy; significant impairments in articulation, facial expression

Question 32

What are the two branches of CN VIII?

Answer 32

auditory, vesitbular

Question 33

What are the five branches of CN IX?

Answer 33

branchial motor, visceral motor, visceral sensory, general sensory, special sensory

Question 34

What does the branchial motor of IX do?

Answer 34

voluntary control of stylopharyngeus (elevates larynx and pharynx during swallowing and speech)

Question 35

What does the visceral motor branch of IX do?

Answer 35

innervates the ipsilateral parotid salivary gland.

Question 36

What does the visceral sensory branch of IX do?

Answer 36

baroreceptors of carotid sinus and chemoreceptors of the carotid body

Question 37

What does the General Sensory branch of IX do?

Answer 37

pain, temperature, and touch of external ear, surface of TM, walls up upper pharynx, and posterior on third of the tongue

Question 38

What does the Special sensory branch of IX do?

Answer 38

taste from posterior 1/3 of tongue

Question 39

so in general: CN IX?

Answer 39

stylopharyngeus (elevates larynx and pharynx), salivary, sensation in a lot of places, including upper pharynx and back of tongue, taste on back of tongue

Question 40

LMN damage to CN IX

Answer 40

poor pharyngeal and laryngeal elevation during swallowing, loss of taste from back of tongue, absent gag reflex (possibly)

Question 41

What are the five branches of CN X?

Answer 41

branchial motor, visceral motor, visceral sensory, general sensory, special sensory

Question 42

What are the three major branches of the branchial motor branch of CN X?

Answer 42

pharyngeal, superior laryngeal, recurrent laryngeal

Question 43

What does the pharyngeal branch of CN X do?

Answer 43

motor innervation to constrictors, tensor veli palatini, salpingopharyngeus, palatopharyngeus, and palatoglossus

Question 44

What does the superior laryngeal branch of CN do?

Answer 44

exterior: motor for inferior constrictor and cricothyroid muscle; interior: sensory for larynx

Question 45

What does the recurrent laryngeal branch of CN X do?

Answer 45

innervate all intrinsic laryngeal muscles except cricothyroid

Question 46

What does the visceral motor branch of CN X do?

Answer 46

innervate smooth muscle and glands of pharynx, larynx, thoracic and abdominal viscera... "rest and digest"

Question 47

Unilateral LMN damage to X results in what?

Answer 47

hoarseness (due to paralysis of one side of larynx), difficulty swallowing, soft palate droops on the affected side and the uvula droops on the opposite side

Question 48

Bilateral LMN damage to X results in what?

Answer 48

severe problems in voice, resonance, and swallowing.

Question 49

Unilateral UMN damage to X results in what?

Answer 49

harsh voice, less severe effects due to bilateral innervation

Question 50

What does XI do?

Answer 50

courses with X and provides some motor innervation to pharynx and larynx

Question 51

What does CN XII do?

Answer 51

motor to the tongue (except palatoglossus)

Question 52

unilateral LMN damage to XII does what?

Answer 52

ipsilateral lingual paralysis; tongue is flaccid and will atrophy; deviates to weak side

Question 53

bilateral LMN damage to XII does what?

Answer 53

significant impairment

Question 54

UMN damage to XII does what?

Answer 54

loss of skilled motor movements in tongue