Cranial nerve functions

Question 1

Describe the function of the olfactory nerve

Answer 1

Special sensory – smell

Question 2

Describe the function of the optic nerve

Answer 2

Special sensory – vision

Question 3

Describe the function of the oculomotor nerve

Answer 3

Motor – levator palpebrae superioris, superior rectus, inferior rectus, medial rectus and inferior oblique
Parasympathetic – sphincter pupillae and ciliary muscles of the eye

Question 4

Describe the function of the trochlear nerve

Answer 4

Motor – superior oblique

Question 5

Describe the function of the ophthalmic division of the trigeminal nerve

Answer 5

Sensory – forehead & scalp, frontal & ethmoidal sinus, upper eyelid & conjunctiva, cornea & dorsum of nose
Parasympathetic – lacrimal gland

Question 6

Describe the function of the maxillary division of the trigeminal nerve

Answer 6

Sensory – lower eyelid & conjunctiva, cheeks & maxillary sinus, nasal cavity & lateral nose, upper lip, upper molar, incisor and canine teeth & superior palate
Parasympathetic – lacrimal gland & nasal glands

Question 7

Describe the function of the mandibular division of the trigeminal nerve

Answer 7

Sensory – mucous membranes & floor of oral cavity, external ear, lower lip, chin, anterior 2/3 tongue & lower molar, incisor & canine teeth
Motor – muscles of mastication: medial pterygoid, lateral pterygoid, masseter, temporalis; anterior belly of digastric and mylohyoid, tensor veli palatini & tensor tympani
Parasympathetic – submandibular, sublingual & parotid gland

Question 8

Describe the function of the abducens nerve

Answer 8

Motor – lateral rectus

Question 9

Describe the function of the facial nerve

Answer 9

Motor – muscles of facial expression, posterior belly of digastric, stylohyoid & stapedius
Sensory – small area around the concha of the external ear
Special sensory – taste to anterior 2/3 of tongue
Parasympathetic – submandibular & sublingual salivary glands, nasal, palatine & pharyngeal mucous glands & lacrimal glands

Question 10

Describe the function of the vestibulocochlear nerve

Answer 10

Special sensory – hearing & balance

Question 11

Describe the function of the glossopharyngeal nerve

Answer 11

Sensory – oropharynx, carotid body and sinus, posterior 1/3 tongue, middle ear cavity & eustachian tube
Special sensory – taste to posterior 1/3
Parasympathetic – parotid gland
Motor – stylopharyngeus muscle of pharynx

Question 12

Describe the function of the vagus nerve

Answer 12

Sensory – skin of external acoustic meatus, internal surfaces of laryngopharynx and larynx, visceral sensation to the heart & abdominal viscera
Motor – majority of muscles of pharynx, soft palate & larynx
Parasympathetic – smooth muscle of trachea, bronchi, GI tract & regulates heart rhythm

Question 13

Describe the function of the accessory nerve

Answer 13

Motor – sternocleidomastoid & trapezius

Question 14

Describe the function of the hypoglossal nerve

Answer 14

Motor – all extrinsic and intrinsic muscles of the tongue (except palatoglossus)