Cranial Nerves

Question 1

Which CNs are purely sensory

Answer 1

CNI, II, VIII

Question 2

Which CNs are purely motor

Answer 2

CNIII, IV, VI, XI, XII

Question 3

Which CNs are mixed nerves

Answer 3

CN V, VII, IX, X

Question 4

Which motor column is most medial?

Answer 4

somatic motor

Question 5

What is the order of motor column from medial to lateral

Answer 5

somatic, brachial, visceral

Question 6

What is the order of sensory column from medial to lateral

Answer 6

visceral, somatic, special sensory

Question 7

which CN nuclei are in the somatic motor column

Answer 7

CNIII, IV, VI, XII

Question 8

which CN nuclei are in the brachial motor column

Answer 8

trigem and facial in pons
glossopharyngeal and vagus in medulla

accessory in the spinal cord

Question 9

which muscles does CNV supply?

Answer 9

muscles of mastication
tensor tympani
tensor veli palatini

(T for T)

Question 10

which muscles supply the muscles of the pharynx and larynx

Answer 10

Vagus for all pharynx and larynx muscles except for stylopharygeus, supplied by the glossopharyngeal

Question 11

What is the name of nucleus enclosing both CNX and CNIX

Answer 11

nucleus ambiguus behind the inferior olive

Question 12

What are the nuclei for visceral efferents

Answer 12

Edinger-Westfal nucleus for CNIII in midbrain
superior salivatory nucleus for VII in pons
inferior salivatory nucleus for IX in medulla
dorsal motor nucleus of X in medulla

Question 13

the nucleus __________ is responsible for visceral afferent, which has inputs from CN ____, ____, and _____ . The visceral afferents have ______ and _______ functions

Answer 13

nucleus solitarius
VII, IX, X
taste
autonomic

Question 14

Which nerve in the visceral afferent nucleus does not have autonomic function?

Answer 14

VII

Question 15

Nucleus Solitarius extends from ________ to ________. The rostral portion is called ______, receiving inputs from ______ and ______. The caudal portion is called ________, which is mainly responsible for control of ________ function

Answer 15

pons 
nucleus gracilis 
gustatory nucleus 
taste buds 
palate 
visceral sensory division 
cardiovascular

Question 16

Which nerves are included in the somatic sensory nucleus?

Answer 16

V, VII, IX, X

Question 17

Meningioma can damage the olfactory nerve, how is the sense of smell affected?

Answer 17

anosmia, but also get sudden episodes of hallucinating smell, typically a smell of burning rubber

Question 18

What is the most common cause of anosmia?

Answer 18

common cold

Question 19

Where do the axons from olfactory bulb project to?

Answer 19

gustatory nucleus and insula cortex

Question 20

Oculomotor nerve innervates four of the six extraocular muscles. Trochlear nerve innervates _________ and abducent innervates the _______. All three nerves exit together in the __________, along with the ______ branch of ______

Answer 20

superior oblique 
lateral rectus 
superior orbital fissure 
opthalmic 
trigeminal nerve

Question 21

Which nerve exiting the superior orbital fissure is the most susceptible to injury? Why?

Answer 21

CNVI, because it has a long way to travel

Question 22

what somatic motor function does CNIII have?

Answer 22

somatic motor for 4/6 extra-ocular muscles

elevates eyelid via levator palpebrae superioris

Question 23

what PNS function does the ocularmotor nerve have

Answer 23

constriction of the pupil

focussing of the ciliary muscle

Question 24

Are the PNS and somatic motor functions of CNIII segregated at brainstem?

Answer 24

Yes, they arise from different nuclei, but travel together through the SOF

Question 25

why do cranial nerves often get affected together when there is a disease

Answer 25

CNs often exit in groups

Question 26

which nerves exit from the auditory canal

Answer 26

facial and vestibulocochlear

Question 27

which nerves exit from the jugular foramen

Answer 27

vagus and accessory

Question 28

what are the three reflexes used for testing brainstem function

Answer 28

pupillary light reflex blink reflex gag reflex

Question 29

what the pupillary light reflex assess?

Answer 29

the function of the midbrain

Question 30

what is the efferent and afferent nerve for pupillary light reflex

Answer 30

afferent via optic nerve at the retina | efferent via ocularmotor tot he iris

Question 31

where are the autonomic fibres of CNIII from?

Answer 31

Edinger-Westfal nucleus

Question 32

a common viral cause of cranial nerve damage is?

Answer 32

Herpes Zoster (Shingles) on CNV. Virus lies dormant in trigem ganglion and can reactivate when the immune system is down

Question 33

Trigeminal is mainly a ______ nerve, supplying the ________ function for the face, but it also has _______ motor fibres, innervating muscles of _________ and also the _______ in the inner ear

Answer 33

``` sensory somatic sensory brachial mastication tensor tympani ```

Question 34

T/F Trigem supplies the sensory function of the brain tissue only

Answer 34

False, it also supplies the meninges

Question 35

Trigem has nuclei that run from midbrain to spinal cord. What are the four nuclei?

Answer 35

mesencephalic chief sensory spinal trigeminal nucleus motor nucleus

Question 36

Pain sensation of trigem is located in the ________, proprioception is in __________, and everything else goes to _________

Answer 36

spinal trigeminal mesencephalic chief sensory

Question 37

which division of trigem does the trigem motor nerve travel with?

Answer 37

mandibular V3

Question 38

What does the corneal blink reflex test for?

Answer 38

pons function

Question 39

Sensory input of corneal reflex is mediated by ________ of ________, which synapse onto interneurons ________, and excite efferent neurons of _______, and then the eys blink

Answer 39

opthalmic division trigeminal nerve bilaterally facial nerve (on both sides) (so that blinking occurs on both eyes when stimulating only one)

Question 40

Facial nerve is predominantly a ______ nerve, supplying the ______ of the face. However it also has ________, ________, and ________ functions

Answer 40

``` brachial motor muscles PNS efferent visceral sensory somatic sensory ```

Question 41

Which muscles does the facial nerve innervate in the middle ear? What is it important for?

Answer 41

stapedius | dampening sound

Question 42

digastric muscle is supplied by which nerves?

Answer 42

facial and trigem

Question 43

How does Bell's Palsy occur?

Answer 43

damage to the lower motor neurons of CNVII

Question 44

Facial nerve travels from the brainstem through the _________, first giving a branch called ________. It then gives motor supply to ________ and also ________ branch for taste in the _______ of the tongue. Finally, it gives a posterior motor branch called ________ and also 5 anterior motor branches forming _______ at the parotid gland

Answer 44

``` internal acoustic meatus greater petrosal stapedius chorda tympani anterior 2/3 posterior auricular pes anserinus ```

Question 45

What is the function of greater petrosal branch?

Answer 45

PNS to the eye for lacrimation

Question 46

Does the facial nerve supply the parotid gland?

Answer 46

no, it just passes through the substance of parotid

Question 47

Ocularis oris is supplied by which branch of facial nerve?

Answer 47

temporal

Question 48

Acoustic neuroma is characterised by ________ and ______. Because CNVIII travels with ______ through the ________, there also be loss of _______. Additionally, the lesion may also press on ______ to cause _______

Answer 48

``` gradual hearing loss dizziness CNVII internal acoustic meatus taste CNV facial pain ```

Question 49

Glossopharyngeal supplies the visceral efferent for ______ on the ______ of the tongue. It is the primary sensory nerve for _______ and _______. It also supplies the PNS function to ______ and motor function to ________, which is responsible for ________

Answer 49

``` taste posterior 1/3 pharynx middle ear parotid gland stylopharyngeus palate elevation ```

Question 50

CNIX exits via ________ and it follows _________ to reach the _________ and tongue

Answer 50

jugular foramen stylopharyngeus oropharynx

Question 51

Which muscles does the vagus supply

Answer 51

muscles of the soft palate, pharynx, larynx, upper oesophagus and palatoglossus

Question 52

Gag reflex is used to assess the function of __________. It receives sensory input from _______ and motor out from _______

Answer 52

medulla glossopharyngeal vagus

Question 53

What are the symptoms of spinal accessory nerve damage?

Answer 53

flaccid paralysis, muscle wasting and atrophy of sternomastoid and upper part of trapezius

Question 54

where does CNXI arise from? How does it enter and exit the cranium?

Answer 54

upper 5-6 of cervial spinal cord | via foramen magnum, and exit via jugular foramen with vagus

Question 55

What movements is CNXI responsible for

Answer 55

Shoulder shrug and head turning

Question 56

If you damage your left CNXI, which way can't you turn?

Answer 56

cannot turn to the right (the opposite side)

Question 57

What happens when you damage CNXII

Answer 57

tongue deviation to the damaged side and atrophy

Question 58

T/F CNXII deficit is usually congenital

Answer 58

True if the damage is isolated to only CNXII. Because other nerves travel with CNXII, there are usually several CN deficits occurring at the same time

Question 59

where does the CNXII exit?

Answer 59

hypoglossal foramen