CRANIAL NERVES & INNERVATION

CRANIAL NERVE I

olfactory nerve

• sense of smell

• sensory

• VA

• bipolar neurons

CRANIAL NERVE II

optic nerve

• sense of vision

• sensory

• SA

• bipolar neurons

CRANIAL NERVE III

oculomotor nerve

• innervates superior rectus, inferior rectus, medial rectus, and inferior oblique

• motor

• SE and VE

• multipolar neurons

CRANIAL NERVE IV

trochlear nerve

• eye movement

• innervates superior oblique

• motor

• SE

• multipolar

CRANIAL NERVE V

trigeminal nerve

• facial sensation, muscles of mastication

• BOTH

• SE and SA

• multipolar and pseudo unipolar

CRANIAL NERVE VI

abducens nerve

• innervates lateral rectus muscle, which abducts eye

• motor

• SE

• multipolar

CRANIAL NERVE VII

facial nerve

• facial expression, taste, secretions of salivary and lacrimal glands

• BOTH

• SE, VE, SA, VA

• multipolar and pseudounipolar

CRANIAL NERVE VIII

vestibulocochlear nerve

• hearing and equilibrium

• sensory

• SA

• bipolar

CRANIAL NERVE IX

Glossopharyngeal Nerve

• gag reflex, pharyngeal muscles

• BOTH

• SE, VE, SA, VA

• multipolar and pseudounipolar

CRANIAL NERVE X

Vagus nerve

• laryngeal muscles (voice), pharyngeal muscles (swallowing)

• BOTH

• SE, VE, SA, VA

• multipolar and pseudounipolar

CRANIAL NERVE XI

spinal accessory nerve

• head-turning

• motor

• SE

• multipolar

CRANIAL NERVE XII

Hypoglossal nerve

• tongue movement

• motor

• SE

• multipolar

somatic efferent nerves

innervate skeletal muscle
- CN 3, 4, 5, 6, 7, 9, 10, 11, 12

somatic afferent

sensations of vision, tactile and pain, hearing and equilibrium
- CN 2, 5, 7, 8, 9, 10

visceral efferent

innervation of smooth muscle, cardiac muscle, and glands
- CN 3, 7, 9, 10

visceral afferent

sensations from viscera including olfaction and taste
- CN 1, 7, 9, 10

which cranial nerves have bipolar neurons?

CN I, II, VIII

which cranial nerves has pseudounipolar neurons?

CN V, VII, IX, X

lesion of oculomotor nerve (III)

• eye deviation inferiorly and laterally (lateral strabismus)

• eyelid droops (ptosis)

• pupil dilates (mydriasis)

• pupillary light reflex lost

Lesion of trochlear nerve (IV)

eye deviates superiorly and laterally

lesion of abducens nerve (VI)

eye deviates medially (medial strabismus)

lesion of spinal accessory nerve (XI)

• difficulty shrugging ipsilateral shoulder

• difficulty turning head in contralateral direction

lesion of hypoglossal nerve (XII)

• tongue deviates ipsilaterally when protruded

• slurred speech (dysarthria)

lesion of olfactory nerve (I)

loss of smell (anosmia)

lesion of optic nerve (II)

ipsilateral blindness (anopsia)

Lesion of vestibulocochlear nerve (VIII)

• ipsilateral deafness

• loss of equilibrium

lesion of trigeminal nerve (V)

• ipsilateral loss of tactile and pain for forehead and midface (V1 and V2)

• jaw deviates ipsilaterally when opened (V3)

• ipsilateral loss of tactile and pain for lower face (including anterior 2/3 tongue)

lesion of facial nerve (VII)

• ipsilateral paralysis of muscles of facial expression (Bell's palsy)

• ipsilateral loss of lacrimation and salivation

• ipsilateral loss of taste from anterior 2/3 of tongue

lesion of glossopharyngeal nerve (IX)

• ipsilateral loss of taste from posterior 1/3 of tongue

• loss of gag reflex (sensory limb)

lesion of vagus nerve (X)

• uvula deviates contralaterally

• loss of gag reflex (motor limb)

• dysarthria