Spencer's Cranial Nerves Deck

Question 1

Which two cranial nerves are not technically “cranial nerves”?

Answer 1

CN I & II

Question 2

The Olfactory nerve is really an extension of what part of the brain?

Answer 2

the Telencephalon

Question 3

The Optic nerve is really an extension of what part of the brain?

Answer 3

the Diencephalon

Question 4

Where does CN I principally exit the skull?

Answer 4

cribiform foramina

Question 5

Where does CN I synapse?

Answer 5

the olfactory bulb and tract

Question 6

Where does sensory input for CN I first arise?

Answer 6

receptors in the nasal cavity

Question 7

What clinical presentations would follow loss of function of CN I?

Answer 7

anosmia

Question 8

Where does CN II first receive sensory input?

Answer 8

the retina

Question 9

What specific type of sensory information is relayed by CN I & II

Answer 9

special sensory

Question 10

What pathway of the optic nerve lies between the optic canal and optic tract?

Answer 10

the optic chiasm

Question 11

What clinical findings would follow a loss of function of CN II?

Answer 11

blindness, loss of pupillary light reflex, and visual field problems

Question 12

Where does CN III originate?

Answer 12

the midbrain

Question 13

Where does CN II principally exit the skull?

Answer 13

the optic canal

Question 14

Where does CN III principally exit the skull?

Answer 14

the superior orbital fissure (SOF)

Question 15

CN III has somatic motor innervation of which extraoccular muscles?

Answer 15

inferior oblique, inferior rectus, medial rectus, superior rectus and the levator palpebrae superioris

Question 16

CN III has visceral motor innervation of which eye structures?

Answer 16

sphincter pupillae (constrictor) and ciliary muscle (accomodation)

Question 17

What are the clinical findings following a loss of function in CN III?

Answer 17

Ptosis, mydriasis, loss of pupillary light reflex,and eyes move down and out

Question 18

Where do the visceral motor neurons in CN III synapse?

Answer 18

the ciliary ganlgion

Question 19

Where does CN IV orginate in the brain?

Answer 19

the midbrain

Question 20

Through which cranial fossa does CN IV exit through?

Answer 20

the Superior orbital fissure (SOF)

Question 21

Which muscle is innervated by the CN IV somatic motor division?

Answer 21

the superior oblique

Question 22

What clinical findings would follow a loss of function to CN IV?

Answer 22

Inability to look inferiorly and medially

Question 23

What is the origin of CN VI in the brain?

Answer 23

the pons

Question 24

Through which cranial fossa does CN VI exit?

Answer 24

the superior orbital fissure (SOF)

Question 25

Which muscle is innervated by the CN VI somatic motor division?

Answer 25

the lateral rectus

Question 26

What clinical findings would follow a loss of function of CN VI?

Answer 26

inability to look laterally

Question 27

Where does CN V originate?

Answer 27

the pons

Question 28

What are the names of the three branches of CN V?

Answer 28

Ophthalmic branch (V-1), Maxillary branch (V-2), Mandibular branch (V-3)

Question 29

Through which cranial fossa does CN V-1 exit the skull?

Answer 29

the Superior orbital fissure

Question 30

CN V-1 provides sensory innervation of what areas?

Answer 30

the scalp, forehead, upper eyelid, cornea, and bridge of the nose

Question 31

Through what cranial fossa does CN V-2 exit the skull?

Answer 31

the foramen rotundum

Question 32

What areas does CN V-2 provide sensory innervation of?

Answer 32

the sides of then nose, lower eyelid, upper lip, maxillary teeth, gums, palate, nasal cavity and paranasal sinuses

Question 33

Through which structure does CN V-2 pass to innervate the skin of the face?

Answer 33

the infraorbital foramen

Question 34

Through which cranial fossa does CN V-3 exit the skull?

Answer 34

foramen ovale

Question 35

To which structures does CN V-3 provide sensory innervation?

Answer 35

lower lip, mandibular teeth, gums, palate, anterior tongue

Question 36

Through which structure does CN V-3 pass to innervate the skin of the chin?

Answer 36

mental foramen

Question 37

To which major muscles does CN V-3 provide somatic motor innervation?

Answer 37

the temporalis and masseter (elevate mandible) and the medial and lateral pterygoid muscles (side to side motion of mandible)

Question 38

To which additional muscles does CN-V3 provide somatic motor innervation?

Answer 38

tensor tympani, tensor veli palatini, mylohyoid, and anterior digastric muscles

Question 39

What constitutes a consensual reflex?

Answer 39

a reflex in which triggering one side of the body will also trigger the reflex on the other side

Question 40

Before reaching its branch point, CN VII passes through what foramen of the skull?

Answer 40

internal acoustic meatus

Question 41

Where does CN VII originate in the brain?

Answer 41

the pons

Question 42

What is the path of the facial nerve proper after the branch point?

Answer 42

stylomastoid foramen -> parotid gland -> 5 branches to muscles of facial expression

Question 43

the facial nerve proper provides what type of innervation?

Answer 43

branchial motor innervation to the muscles of facial expression

Question 44

What clinical findings would accompany a disruption in or loss of function of the facial nerve proper?

Answer 44

facial palsy

Question 45

What are the three main branches of CN VII?

Answer 45

facial nerve proper, chorda tympani nerve, and greater petrosal nerve

Question 46

What is the pathway of the chorda tympani nerve after the branch point?

Answer 46

tympanic membrane -> petrotympanic fissure -> paired pathway with lingual branch of CN V-3

Question 47

What type of innervation is provided by the chorda tympani nerve?

Answer 47

VM- submandibular & sublingual salivary glands SS- taste for anterior 2/3 tongue

Question 48

What clinical findings would accompany a disruption in or loss of function of the chorda tympani nerve?

Answer 48

loss of taste and reduced salivation

Question 49

What is the pathway of the greater petrosal nerve after the branch point?

Answer 49

palatine branches

Question 50

What type of innervation is provided by the greater petrosal nerve?

Answer 50

VM- lacrimal, nasal, palatine glands SS- taste from palate

Question 51

What clinical findings would accompany a disruption in or loss of function of the greater petrosal nerve?

Answer 51

loss of lacrimation, dry nasal cavity

Question 52

What is the pathway that sensory information relayed by CN VIII travels to reach the brain?

Answer 52

cochlea & SC canals -> internal acoustic meatus -> pons

Question 53

What type of information is relayed to the brain by CN VIII?

Answer 53

SS- hearing and balance

Question 54

Which nuclei of CN VIII relay information about sound? To which part of the brain?

Answer 54

cochlear nuclei; pons

Question 55

Which nuclei of CN VIII relay information about balance? To which part of the brain?

Answer 55

vestibular nuclei; pons & medulla oblongata

Question 56

What clinical findings would accompany a disruption in or loss of function of CN VIII?

Answer 56

loss of hearing and balance (equillibrium)

Question 57

Where do CN IX & X originate in the brain? Where do they exit the skull?

Answer 57

medulla; jugular foramen

Question 58

What functions are innervated by CN IX?

Answer 58

BM- stylopharyngeus VM- parotid gland SS- taste for posterior 1/3 tongue GS- posterior 1/3 tongue, oral pharnyx VS- carotid sinus & body

Question 59

What functions are innervated by CN X?

Answer 59

BM- muscles of palate, pharynx, larynx VM- thoracic & abdominal viscera GS- laryngopharnyx, larynx VS- thoracic & abdominal viscera

Question 60

Where does CN XI orginate in the brain and through what pathways does it exit the skull?

Answer 60

upper cervical spinal cord & medulla; foramen magnum & jugular foramen

Question 61

What type of innervation is provided by CN XI?

Answer 61

BM- sternocleidomastoid & trapezius

Question 62

What clinical findings would accompany injury or loss of function of CN XI?

Answer 62

difficulty shrugging shoulders or rotating head to look over opposite shoulder

Question 63

Where does CN XII orginate in the brain, and how does it exit the skull?

Answer 63

medulla; hypoglossal canal

Question 64

What innervation is provided by CN XII?

Answer 64

SM- control of tongue movements (genioglossus muscle)

Question 65

What clinical findings would accompany an injury or loss of function to CN XII?

Answer 65

loss of motor function to tongue; tongue deviates to one side when outside of mouth

Question 66

The phrase “lick your wound” applies to the scenario of an injured/impinged CN XII how?

Answer 66

The tongue deviation, when outside of mouth, will be to the side that is injured. I.e. right injury -> right deviation

Question 67

What are the five branches of the facial nerve proper?

Answer 67

temporal, zygomatic, buccal, marginal mandibular and cervical

Question 68

The greater petrosal nerve joins what other nerve as it courses superiorly to the lacrimal gland?

Answer 68

the maxillary branch of the trigeminal nerve (CN V-2)

Question 69

The chorda tympani nerve joins what other nerve as it courses to the tongue?

Answer 69

the mandibular branch of the trigeminal nerve (CN V-3)

Question 70

Which two nerves are involved in the corneal reflex?

Answer 70

CN V-1 (sensory) and the chorda tympani (CN VII) (motor)

Question 71

Where do all sympathetic nerves in the head orginate?

Answer 71

T1 spinal cord

Question 72

Which cranial nerves have parasympathetic activity?

Answer 72

CN III, VII, IX, and X