Cranial NervesCranial Nerves

The “FACE” of Cranial Nerves

I OlfactoryII OpticIII OculomotorIV TrochlearV Trigeminal

VI AbducensVII FacialVIII AcousticIX Glossopharyngeal

X VagusXI Spinal AccessoryXii Hypoglossal

Cranial Nerves

Cranial NervesCranial Nerves CN I – Olfactory Nerve Sensory nerve

Transmits the sense of smell from the nasal cavity.

This nerve has access to the cerebral cortex, but does not pass through the thalamus like other cranial nerves.

REMEMBER: Thalamus acts like a switchboard relaying info to parts of brain.

How good is your sense of smell?

While pinching your nose closed and closing your eyes, eat a jelly bean.

Can you tell what flavor it is?

Cranial NervesCranial Nerves CN II – Optic Nerve Special Sensory Transmits visual signals from

the retina of the eye to the brain

Say the color, not the word

How good are you at counting?

Cranial NervesCranial Nerves CN III – Occulomotor Nerve Motor nerve It controls the muscles that

allow for visual tracking and fixation by the eye

Dilate or constrict our pupils in response to changing light conditions.

Raise our eyelids

Cranial NervesCranial Nerves CN IV – Trochlear Nerve Motor nerve Plays a role in the movement

of the eyes. Especially important for

looking down and looking in toward a midline object.

Cranial NervesCranial Nerves CN V – Trigeminal Nerve

Mixed nerve: sensory and motor

Contains the sensory fibers of pain and touch from the face

Also controls muscles involved in mastication (chewing)

Cranial NervesCranial Nerves CN VI – Abducens Nerve Motor nerve

Stimulates the lateral eye muscle to turn the eye outward.

Longest of all cranial nerves; more easily injured.

Nerve crosses to both eyes. If one side injured, eyes do not move together causing double vision or lazy eye.

Cranial NervesCranial Nerves CN VII – Facial Nerve Mixed nerve: motor and sensory

Controls the muscles used in smiling, frowning, and other facial expressions.

It also helps produce taste in two-thirds of the tongue and

Allows for sensations of touch and pain from the ear.

Cranial NervesCranial Nerves CN VIII – Acoustic (Vestibulocochlear) Sensory nerve Consists of two separate parts.

“Cochlear” nerve carries the sensation of hearing from the ear to the brain.

“Vestibular “ nerve carries information about position and movements of the head = balance.

Cranial NervesCranial Nerves CN IX – Glossopharyngeal

Nerve Mixed nerve: sensory and motor

Allows for taste on the back portion of the tongue

Provides sensations of pain and touch from the tongue and tonsils

participates in the control of muscles used during swallowing.

Cranial NervesCranial Nerves CN X – Vagus Nerve Mixed nerve: sensory and motor It controls the sensory and motor

functions of the heart and glands. It also participates in the process

of digestion. Only nerve that extends out into

the body.

Cranial NervesCranial Nerves CN XI – Spinal Accessory

Nerve Motor nerve Allows the trapezius muscle and

sternocleidomastoid muscle to control the movements of the head = tilt your head

Cranial NervesCranial Nerves CN XII – Hypoglossal Nerve Motor nerve Allows the tongue to move

properly; helps in speech and moving food to back of mouth for swallowing.