Cranial Nerves Overview

Proprioceptors are specialized receptors located in muscles, tendons, or joints that supply information regarding body position and movement.

I - Olfactory:
- Sensory Origin: Olfactory epithelium of nose (smell)
- Motor Innervation: None
II - Optic:
- Sensory Origin: Retina of eye (vision)
- Motor Innervation: None
III - Oculomotor:
- Sensory Origin: Proprioceptors of eyeball muscles
- Motor Innervation: Muscles that move eyeball, change shape of lens, and constrict pupil
IV - Trochlear:
- Sensory Origin: Proprioceptors of eyeball muscles
- Motor Innervation: Muscles that move eyeball
V - Trigeminal:
- Sensory Origin: Teeth and skin of face
- Motor Innervation: Some muscles used in chewing
VI - Abducens:
- Sensory Origin: Proprioceptors of eyeball muscles
- Motor Innervation: Muscles that move eyeball

VII - Facial:
- Sensory Origin: Taste buds of anterior part of tongue
- Motor Innervation: Muscles used for facial expression, submaxillary salivary glands, and sublingual salivary glands
VIII - Vestibulocochlear (auditory):
- Vestibular branch Sensory Origin: Semicircular canals of inner ear (senses of movement, balance, and rotation)
- Cochlear branch Sensory Origin: Cochlea of inner ear (hearing)
- Motor Innervation: None
IX - Glossopharyngeal:
- Sensory Origin: Taste buds of posterior third of tongue and lining of pharynx
- Motor Innervation: Parotid salivary gland and muscles of pharynx used in swallowing
X - Vagus:
- Sensory Origin: Nerve endings in many internal organs (e.g., lungs, stomach, aorta, larynx)
- Motor Innervation: Parasympathetic fibers to heart, stomach, small intestine, larynx, esophagus, and other organs
XI - Spinal accessory:
- Sensory Origin: Muscles of shoulder
- Motor Innervation: Muscles of neck and shoulder
XII - Hypoglossal:
- Sensory Origin: Muscles of tongue
- Motor Innervation: Muscles of tongue