Cranial Nerves

Question 1

CNI: Name, type, function and damage to results in what?

Answer 1

Olfactory. CNI innervates the olfactory bulb. Sensory. Damage to the olfactory nerve results in anosmia.

Question 2

CNII: Name, type, function and damage to results in what?

Answer 2

Optic. CNII innervates the retina. Sensory. Damage to this nerve can result in loss of vision, depending on where the damage to the nerve occurs. May not be able to drive.

Question 3

CNIII: Name, type, function and damage to results in what?

Answer 3

Oculomotor. CNIII innervates muscles of the eye. Motor. Damage may result in ptesosis (squinty eye). They won’t be able to see straight ahead, so vision will be difficult. Driving will be challenging.

Question 4

CNIV:

Answer 4

Trochlear. Motor. Innervates superior oblique muscle. Seeing double - images are stacked instead of side-by-side. Difficulty descending stairs.

Question 5

CNV

Answer 5

Trigeminal. This is the largest of the cranial nerves. Both sensory and motor. Name trigeminal stems from the fact that this nerve has three major branches: opthalmic, maxilliary, mandibular. Mastication and sensation to eye nose face. Damage may result in difficulty closing mouth, and loss of sensation to the phonation. Difficulty chewing or articulating.

Question 6

CNVI

Answer 6

Abducens. Motor. Innervate lateral rectus muscle. Function: rotating eye ball outward. Damage may result in inability to abduct eye balls (eyes crossed) which may result in double vision (diplopia). Difficulty driving due to depth perception deficits.

Question 7

CNVII

Answer 7

Facial. Both. Innervates buccal muscles and orbiculares oris. Function is sensation to anterior 2/3 of tongue (taste) and facial movement. Damage may result in bells palsy: paralysis to facial muscles. Difficulty enjoying food and persistent eye problems.

Question 8

CNVIII

Answer 8

Vestibularcochlear. Sensory. Function is hearing and balance. Innervates the cochlea. May cause tinitis, vertigo, and hearing loss. Difficulty walking, nausea, and hearing loss. Difficulty communicating with others verbally.

Question 9

CNIX

Answer 9

Glossopharyngeal. Both. Innervates: pharynx and larynx. The glossopharyngeal nerve provides taste sensation to the posterior 1/3 of the tongue. The stylopharyngeus muscle of the pharynx is innervated by the glossopharyngeal nerve. This muscle acts to shorten and widen the pharynx, and elevate the larynx during swallowing. Dysphagia. Effect: aspiration.

Question 10

CNX

Answer 10

Vagus. Both. Sensory to the visceral organs and base of tongue. Provides motor innervation to the majority of the muscles of the pharynx, soft palate and larynx. Damage: dysphagia, poor phonation (weak or hoarse voice). Effect: food modification and decreased ability to communicate verbally.

Question 11

CNXI

Answer 11

Accessory. Motor. Innervates the sternoclydomastoid, trapezius, pharynx, upper larynx, and soft palate. Damage may result in difficulty with velopharyngeal closure which may result in nasal regurgitation or hypernasality. Effects: poor breath support and voicing.

Question 12

CNXII

Answer 12

Hypoglossal. Motor. Innervates: muscles of the tongue. Damage will result in dysphagia and articulation (dysarthria).