Cranial Nerves

Olfactory function (I)

Provides a sense of smell (afferant)

Olfactory assess (I)

Test smell with each nostril while eyes are closes (afferent)

Optic function (II)

Vision (afferant)

Optic assess (II)

Pupil response to light, Snellen chart (afferent)

Oculamotor function (III)

Eye movement & pupil response (efferant)

Oculamotor function (III)

Eye movement up, down, and medially & pupil response (efferant)

Trochlear function (IV)

Eye movement (down and inward) (efferant)

Trochlear asses (IV)

Without head movement, note for smooth movement of the eyes inwards towards the nose (efferant)

Trigeminal function (V)

Sensation & chewing (both)

Trigeminal assess (V)

Clench down teeth and palpate masseter muscle, open mouth against resistance (both)

Abducens function (VI)

Lateral eye movement (efferent)

Abducens assess (VI)

Without head movement, note how eyes move side to side (efferent)

Facial function (VII)

Facial expression & taste (both)

Facial assess (VII)

Note ability to raise eyebrows, close eyes tightly, smile, puff cheeks, and taste on anterior 2/3 of the tongue (both)

Vestibulocochlear function (VIII)

Hearing and balance (afferent)

Vestibulocochlear assess (VIII)

Cover one ear and whisper words to test hearing, stand with feet together, eyes close and nothing any unsteadiness for balance (both)

Glossopharyngeal function (IX)

Gag reflex, swallowing, taste (both)

Glossopharyngeal assess (IX)

Say “ah” noting uvula movement, check swallowing (both)

Vagus function (X)

Regulates PNS, gag reflex (both)

Vagus assess (X)

Test gag reflex on posterior pharynx with a tongue blade (both)

Accessory function (XI)

Shoulder shrug and head turn (efferent)

Accessory assess (XI)

Shrug both shoulders and turn head against resistance (efferent)

Hypoglossal function (XII)

Tongue movement (efferent)

Hypoglossal assess (XII)

Note ability to stick out tongue and move it side to side (efferent)