Summary of Cranial Nerves

Cranial Nerve	Function	Usual complaint	Test of Function	Physical findings
Olfactory	Smell	None or loss of taste if bilateral	Sense of smell with each nostril tested individually	No response to olfactory stimuli
Optic	Vision	Loss of vision	Visual acuity, visual fields of each eye	Decreased visual acuity or loss of visual field.
Oculomotor	Eye movement, Pupillary constriction	Double vision	Pupil and eye movement	Failure to move eye in field of motion of muscles. Pupillary abnormalities
Trochlear	Eye movement	Double vision especially on down and medial gaze	Ability to move eye down and in	May be difficult to detect anything if 3rd nerve intact
Trigeminal	Facial, nasal oral sensation and jaw movement	Numbness , Paresthesia	Pinprick sensation on face , corneal reflex and masseter contraction	Decrease d pin and absent corneal reflex. Weakness of masticatory muscle.
Abducens	Eye movement	Double vision on lateral gaze	Moves eye laterally	Failure of eye to abduct
Facial	Facial movement	Lack of facial movement, eye closure,Dysarthria	Facial contraction,Smiling	Asymmetry of Facial contraction
Auditory and vestibular	Hearing balance	Hearing loss, Tinnitus, Vertigo	Hearing test, Nystagmus balance	Decreased hearing, Nystagmus, Ataxia
Glossopharyngeal	Palatal Movement	Trouble with Swallowing	Elevation of Palate	Asymmetric Plate
Vagus	Palatal movement, Vocal cords	Trouble swallowing	Vocal cords	Brassy voice
Spinal Accessory	Turns neck	None	Contraction of sternocleidomastoid and trapezius	Paralysis of sternocleidomastoid muscle
Hypoglossal	Moves tongue	Dysarthria	Protrusion of tongue	Wasting and fasciculation or deviation of tongue