Lecture 9: Cranial Nerves

Question 1

Olfactory Nerve

Answer 1

CN I

Special sensory - smell

Question 2

Optic Nerve

Answer 2

CN II

Special sensory - vision

Question 3

Oculomotor Nerve

Answer 3

CN III

Somatic motor - supply levator palpebrae superioris, superior rectus, medial rectus, inferior rectus, and inferior oblique muscles of the eye

Visceral motor - provides parasympathetic supply to constrictor pupillae and ciliary muscles via ciliary ganglion

Question 4

Trochlear Nerve

Answer 4

CN IV

Somatic motor - supply superior oblique muscle of the eye (down and out motion)

Question 5

Trigeminal Nerve

Answer 5

CN V

Branchial motor - muscles of mastication, tensor tympani, tensor palatini, mylohyoid, anterior belly of digastric

General sensory - from face and scalp as far as top of head, conjunctiva, bulb of eye, mucous membranes of paranasal sinuses, nasal/oral cavities including tongue/teeth, part of external aspect of tympanic membrane, and from meneinges of anterior and middle cranial fossae

Question 6

Abducens Nerve

Answer 6

CN VI

Somatic motor - supply lateral rectus muscle of the eye (moving eyeballs outward)

Question 7

Facial Nerve

Answer 7

CN VII

Branchial motor - supply stapedius, stylohyoid, posterior belly of digastric muscles, muscles of facial expression (buccinator, platysma, occipitalis muscles)

Visceral motor - for stimulation of lacrimal, submandibular, and sublingual glands, as well as mucous membranes of nose/hard and soft palates

General sensory - EAR

Special sensory - taste from anterior 2/3 of tongue and hard/soft palates

Question 8

Vestibulocochlear Nerve

Answer 8

CN VIII

Special sensory - hearing, balance

Question 9

Glossopharyngeal Nerve

Answer 9

CN IX

Branchial motor - supply stylopharyngeus

Visceral motor - supply otic ganglion (sending fibers to stimulate parotid gland)

Visceral sensory - carries subconscious sensation from carotid body and carotid sinus

General sensory - provides general sensation from posterior 1/3 of tongue, skin of external ear, internal surface of tympanic membrane Special sensory - taste from posterior 1/3 of tongue

Question 10

Vagus Nerve

Answer 10

CN X

Branchial motor - striated muscles of pharynx, tongue, larynx (except stylopharyngeus and tensor veli palati)

Visceral motor - to smooth muscle glands of pharynx, larynx, thoracic and abdominal viscera

Visceral sensory - from larynx, trachea, esophagus, thoracic and abdominal viscera, stretch receptors in walls of aortic arch, chemoreceptors in aortic bodies adjacent to arch

General sensory - pharynx and ear

Question 11

Accessory Nerve

Answer 11

CN XI

Branchial motor - supply sternomastoid and trapezius

Question 12

Hypoglossal Nerve

Answer 12

CN XII

Somatic motor - supply all intrinsic and extrinsic muscles of the tongue except palatoglossus

Question 13

Reverse

CN I

Special sensory - smell

Answer 13

Olfactory Nerve

Question 14

Reverse

CN II

Special sensory - vision

Answer 14

Optic Nerve

Question 15

Reverse

CN III

Somatic motor - supply levator palpebrae superioris, superior rectus, medial rectus, inferior rectus, and inferior oblique muscles of the eye

Visceral motor - provides parasympathetic supply to constrictor pupillae and ciliary muscles via ciliary ganglion

Answer 15

Oculomotor Nerve

Question 16

Reverse

CN IV

Somatic motor - supply superior oblique muscle of the eye (down and out motion)

Answer 16

Trochlear Nerve

Question 17

Reverse

CN V

Branchial motor - muscles of mastication, tensor tympani, tensor palatini, mylohyoid, anterior belly of digastric

General sensory - from face and scalp as far as top of head, conjunctiva, bulb of eye, mucous membranes of paranasal sinuses, nasal/oral cavities including tongue/teeth, part of external aspect of tympanic membrane, and from meneinges of anterior and middle cranial fossae

Answer 17

Trigeminal Nerve

Question 18

Reverse

CN VI

Somatic motor - supply lateral rectus muscle of the eye (moving eyeballs outward)

Answer 18

Abducens Nerve

Question 19

Reverse

CN VII

Branchial motor - supply stapedius, stylohyoid, posterior belly of digastric muscles, muscles of facial expression (buccinator, platysma, occipitalis muscles)

Visceral motor - for stimulation of lacrimal, submandibular, and sublingual glands, as well as mucous membranes of nose/hard and soft palates

General sensory - EAR

Special sensory - taste from anterior 2/3 of tongue and hard/soft palates

Answer 19

Facial Nerve

Question 20

Reverse

CN VIII

Special sensory - hearing, balance

Answer 20

Vestibulocochlear Nerve

Question 21

Reverse

CN IX

Branchial motor - supply stylopharyngeus

Visceral motor - supply otic ganglion (sending fibers to stimulate parotid gland)

Visceral sensory - carries subconscious sensation from carotid body and carotid sinus

General sensory - provides general sensation from posterior 1/3 of tongue, skin of external ear, internal surface of tympanic membrane

Special sensory - taste from posterior 1/3 of tongue

Answer 21

Glossopharyngeal Nerve

Question 22

Reverse

CN X

Branchial motor - striated muscles of pharynx, tongue, larynx (except stylopharyngeus and tensor veli palati)

Visceral motor - to smooth muscle glands of pharynx, larynx, thoracic and abdominal viscera

Visceral sensory - from larynx, trachea, esophagus, thoracic and abdominal viscera, stretch receptors in walls of aortic arch, chemoreceptors in aortic bodies adjacent to arch

General sensory - pharynx and ear

Answer 22

Vagus Nerve

Question 23

Reverse

CN XI

Branchial motor - supply sternomastoid and trapezius

Answer 23

Accessory Nerve

Question 24

Reverse

CN XII

Somatic motor - supply all intrinsic and extrinsic muscles of the tongue except palatoglossus

Answer 24

Hypoglossal Nerve