12 Cranial Nerves: Functions, Types, and Anatomy

Cranial Nerves

12 pairs of nerves that originate at the inferior surface of the Cerebrum & Brainstem

Nature of Cranial Nerves

Either primarily Sensory (S), primarily Motor (M), or Mixed (Both) in function

Primary Function of Cranial Nerves

Mediate functions of head, face, neck, and visceral organs

I. Olfactory

Sensory; Smell

II. Optic

Sensory; Vision

III. Oculomotor

Motor; Eyeball, eyelid, iris, lens, ability to blink

IV. Trochlear

Motor; Eyeball movement in up/down and L/R directions (superior oblique)

V. Trigeminal

Both motor and sensory; M: Chewing; S: General feeling of face, cheeks, and eyeballs, the ability to move the jaw

VI. Abducens

Motor; Eyeball movement (lateral rectus)

VII. Facial

Both motor and sensory; M: Facial expressions, tearing, salivation; S: General feeling of tongue, taste

VIII. Vestibulocochlear

Sensory; Balance, hearing (audition), posture

IX. Glossopharyngeal

Both motor and sensory; M: Salivation, swallowing, gagging (pharynx); S: Taste (at tongue)

X. Vagus

Both motor and sensory; M: Viscera, swallowing, speech (tongue, pharynx, larynx), digestion, heart rate; S: Viscera, Tongue, Pharynx, Larynx

XI. Accessory

Motor; Swallowing (pharynx, larynx); Shoulder and neck muscle movement

XII. Hypoglossal

Motor; Chewing, swallowing and speech (tongue)