Anatomy & Phys - The Brain

Front 1

olfactory nerve

Back 1

purely sensory; carries impulses for the sense of smell

Front 2

optic nerve

Back 2

purely sensory; carries impulses for vision

Front 3

oculomotor

Back 3

supplies motor fibers to four of the six muscles (superior, inferior, and medial rectus, and inferior oblique) that direct the eyeball; to the eyelid; and to the internal eye muscles controlling lens shape and pupil size

Front 4

trochlear

Back 4

supplies motor fibers for one external eye muscle (superior oblique)

Front 5

trigeminal

Back 5

conducts sensory impulses from the skin of the face and mucose of the nose and mouth; also contains motor fibers that activate the chewing muscles

Front 6

abducens

Back 6

supplies motor fibers to the lateral rectus muscle, which rolls the eye laterally

Front 7

facial

Back 7

activates the muscles of facial expression and the lacrimal and salivary glands; carries sensory impulses from the taste buds of anterior tongue

Front 8

vestibulocochlear

Back 8

purely sensory; vestibular branch transmits impulses for the snese of balance and cochlear branch transmits impulses for the sense of hearing

Front 9

glossopharyngeal

Back 9

supplies motor fibers to the pharynx (throat) that promote swallowing and saliva production; carries sensory impulses from taste buds of the posterior tongue and from pressure receptiors of the carotid artery

Front 10

vagus

Back 10

fibers carry sensory impulses from and motor impulses to the pharnyx, layrnx, and the abdominal and thoracic viscera; most motor fibers are parasympathetic fibers that promote digestive activity and help regulate heart activity

Front 11

accessory

Back 11

mostly motor fibers that activate the sternocleidomastoid and trapezius muscles

Front 12

hypoglossal

Back 12

motor fibers control tongue movements; sensory fibers carry impulses from the tongue