Cranial Nerves and Foramina

CN I

olfactory n.

sensory only

passes through the cribiform plate

for the special sense of smell

CN II

optic n.

sensory only

passes through the optic foramen

carries the sense of sight

CN III

oculomotor n.

motor only

leaves skull through superior orbital fissure

innervates the muscles of the eye

CN IV

trochlear n.

motor only

emerges from the dorsal brainstem, wraps around the midbrain to inter the orbit by way of the superior orbital fissure.

innervates the superior oblique muscle ONLY

CN V

trigeminal n.

mixed nerve found on the side of the pons

has three divisions

sensory inn. to face, motor to muscles of mastication

V1

opthalmic n.

sensory division

enters skull through the superior orbital fissure

brings general sensory info from the upper face and eye

V2

maxillary n.

sensory division

enters skull through foramen rotundum

sensory info from nose area and upper teeth

V3

mandibular n.

motor AND sensory

transmitted through the foramen ovale

sensation of the lower face, tongue and lower teeth

inn. muscles of mastication

CN VI

abducens n.

motor only

emerges between pons and medulla on ventral brainstem

leaves skull via superior orbital fissure

inn. lateral rectus muscle ONLY (eye abduction)

CN VII

facial n.

sensory AND motor

emerges lateral to abducens, runs through internal acoustic meatus. Motor fibers emerge from stylomastoid foramen onto the face. Sensory neurons land on the anterior 2/3 or tongue.

Motor muscles of facial expression and sense of taste to anterior 2/3 of tongue.

CN VIII

vestibulocochlear n.

sensory only

passes through internal acoustic meatus

hearing and balance

CN IX

glossopharangeal n.

mixed nerve

enters the skull through the jugular foramen

taste and sensation of the posterior 1/3 of tongue

motor fibers to the pharynx

CN X

vagus n.

mixed nerve

transmitted though the jugular foramen

inn smooth muscle of the neck, thorax, and abdomen for motor and sensory (parasympathetic)

CN XI

accessory n.

motor only

rootlets from side of medulla and spinal cord enter the skull through foramen magnum and exits skull through jugular foramen.

inn larynx, pharynx, SCM, traps.

CN XII

hypoglossal n.

motor only, to tongue

exits skull via hypoglossal canal

inn all tongue muscles, intrinsic and extrinsic

cribriform plate

transmits olfactory n. fibers

optic foramen

optic nerve

opthalmic artery

superior orbital fissure

CN III, IV, VI, V1

foramen rotundum

V2

foramen ovale

V3

foramen spinosum

middle meningeal artery

foramen lacerum

internal carotid artery enters cranial vault here

jugular foramen

internal jugular vein, CN IX, X, XI

internal acoustic meatus

CN VII, VIII

stylomastoid foramen

CN VII

hypoglossal canal

CN VII

foramen magnum

vertebral arteries

spinal cord

carotid canal

internal carotid artery enters skull here