Nerves of the cranium

Question 1

Name CN I

Answer 1

olfactory

Question 2

Name CN II

Answer 2

optic

Question 3

Name CN III

Answer 3

oculomotor

Question 4

Name CN IV

Answer 4

Trochlear

Question 5

Name CN V

Answer 5

Trigeminal

Question 6

Name CN VI

Answer 6

Abducens

Question 7

Name CN VII

Answer 7

Facial

Question 8

Name CN VIII

Answer 8

vestibulocochlear

Question 9

Name CN IX

Answer 9

Glossopharyngeal

Question 10

Name CN X

Answer 10

Vagus

Question 11

Name CN XI

Answer 11

Accessory

Question 12

Name CN XII

Answer 12

Hypoglossal

Question 13

What is the modality and function of the olfactory nerve?

Answer 13

sensory

smell

Question 14

What is the modality and function of the optic nerve?

Answer 14

sensory

vision

Question 15

What is the modality and function of the oculomotor nerve?

Answer 15

motor

4 extrinsic eye muscles and levator palpebrae superioris.

helps to adjust and coordinate eye position during movement

GVM: pupillary sphincter

Question 16

What is the modality and function of the trochlear nerve?

Answer 16

motor

superior oblique muscle

enables movement in the eye’s superior oblique muscle. This makes it possible to look down. The nerve also enables you to move your eyes toward your nose or away from it.

Question 17

Compare the oculomotor, trochlear and abducens nerves

Answer 17

Cranial Nerve IV (Trochlear) controls downward eye movement toward the nose, and Cranial Nerve VI (Abducens) controls horizontal eye movement toward the temple. The ability to move the eye in all other directions is controlled by CN III

Question 18

What nerves allows horizontal movement of the eye?

Answer 18

the abducens

towards the temple

Question 19

What nerve allows downward eye movement towards the nose?

Answer 19

Trochlear nerve CNIV

Question 20

What is the largest cranial nerve?

Answer 20

trigeminal

Question 21

What are the 3 branches of the trigeminal nerve?

Answer 21

Ophthalmic (V1), maxillary (V2), and mandibular (V3) nerves.

Question 22

What is the primary function of the trigeminal nerve?

Answer 22

primary function is to provide sensory innervation to the face

Question 23

What is the modality and function of the Ophthalmic nerve (CNV1)

Answer 23

supplies sensory innervation to the structures of the eye, including the cornea, ciliary body, lacrimal gland, and conjunctiva

It provides sensory innervation to the skin, mucous membranes and sinuses of the upper face and scalp.

Question 24

What is the modality and function of the maxillary nerve (CNV 2)?

Answer 24

sensory

Cheeks, lower eye lid, nasal mucosa, upper lip, upper teeth and palate.

(middle third of face)

Question 25

What are the modality and function of the mandibular nerve?

Answer 25

Sensory

anterior 2/3 tongue, skin over mandible and lower teeth.

SVM: muscles of mastication.

The mandibular nerve innervates the lower face including the mandible, lower teeth, and oral mucosa, the anterior two-thirds of the tongue, lower lip, temporomandibular joint, the mastication muscles and some smaller muscles, the skin of the temporal region, an area of the auricle and external acoustic meatus.

Question 26

What is the modality and function of the abducens nerve?

Answer 26

motor

lateral rectus

controls the movement of the lateral rectus muscle, one of the extraocular muscles responsible for outward gaze

towards temporal bone

Question 27

What is the function of the facial nerve?

Answer 27

GSS: sensation to part of ext. ear.
SVS: taste from ant. 2/3 tongue, hard and soft palate.

SVM: muscles of facial expression.

GVM: lacrimal, submandibular, sublingual glands and mucous glands of mouth and nose.

Question 28

What involuntary innervation by the facial nerve effects the glands of the oral cavity and the lacrimal gland?

Answer 28

parasympathetic innervation

Question 29

What is the modality and function of the vestibulocochlear nerve?

Answer 29

sensory

hearing and balance

responsible for the special sensation of hearing, and its vestibular portions are involved in balance, spatial sensation, and posture.

Question 30

What is the function of the glossopharyngeal nerve?

Answer 30

GSS: post. 1/3 tongue, ext. ear, and middle ear cavity.
GVS: carotid body and sinus.

SVS: taste from post. 1/3 tongue.

GVM: parotid gland.

SVM: stylopharyngeus

Question 31

What is the function of the stylopharyngeus muscle?

Answer 31

significant dilating muscle of the nasopharynx. During breathing,

helps the collapse of the dorsal wall of the nasopharynx by supporting the wall during inspiration

Question 32

What is the modality and function of the vagus nerve?

Answer 32

both

GSS: ext. ear, larynx and pharynx.

GVS: larynx, pharynx and, thoracic & abdominal viscera.

SVS: taste from epiglottis region of tongue

GVM: smooth muscles of pharynx, larynx and most of the GIT.

SVM: most muscles of pharynx and larynx.

Question 33

What is the modality and function of the (spinal) accessory nerve?

Answer 33

motor

GSM: trapezius and sternocleidomastoid.

SVM: a few fibres run with CNX to viscera.

This nerve supplies the sternocleidomastoid and trapezius muscles, which have the following functions: Rotation of head away from the side of the contracting sternocleidomastoid muscle. Tilting of the head toward the contracting sternocleidomastoid muscle. Flexion of the neck by both sternocleidomastoid muscles.

Question 34

What is the modality and function of the hypoglossal nerve?

Answer 34

motor

Intrinsic and extrinsic tongue muscles (except the palatoglossus).

It innervates all the extrinsic and intrinsic muscles of the tongue, except for the palatoglossus which is innervated by the vagus nerve. It is a nerve with a solely motor function.