TABLE 9.1. CRANIAL NERVES: ATTACHMENT TO CENTRAL

NERVOUS SYSTEM, GENERAL FUNCTIONS, AND DISTRIBUTION

Cranial Nerve Part of Central Nervous

System from Which

Nerve(s) Enter(s) or

Emerge(s)

General

Functional

Types of

Fibers1

General

Distribu

tion

Num

berName

I Olfactory Forebrain

(prosenceph

alon)

Cerebral

hemispheres

(telencephal

on)

Special sensory

only

Olfactory

mucosa

of nose

II OpticDiencephalo

n

Retina of

eye

III Oculomotor Midbrain (mesencephalon)

Motor only

Intraocul

ar and

four

extraocul

ar

muscles

IV Trochlear Midbrain

One

extraocul

ar muscle

(superior

oblique)

V Trigeminal Brainstem Pons

(mesencepha

lon)

Mix

ed

Motor

root

Derivativ

es of

frontonas

al

process

Sensory

root

and 1st

pharynge

VIAbducent

(abducens)

Junction

between

pons and

medulla

Motor only

One

extraocul

ar muscle

VII FacialMix

ed

Motor

rootDerivativ

es of 2nd

pharynge

al arch

Intermed

iate

nerve

VIIIVestibulococ

hlear

Special sensory

only

Internal

ear

IXGlossophary

ngealMedulla

(myelenceph

alon)

Mixed

Derivativ

es of 3rd

pharynge

al arch

X Vagus

Derivativ

es of 4th

pharynge

al arch

XISpinal

accessorySuperior spinal cord Motor only

Superfici

al layer

of neck

XII Hypoglossal Brainstem

Medulla

(myelenceph

alon)

MixedMuscles

of tongue