The Cranial Nerves and
Cranial Nerve Nuclei
of the Brain Stem
Objectives:
Learn the name and numerical
designation of each of the twelve
cranial nerves
Learn the names and functions of the
cranial nerve nuclei of the brain stem
and the nerves that arise or terminate
in each of these nuclei
Learn the location of each of the cranial
nerve nuclei of the brain stem on the
brain stem model
1
12 pairs of Cranial Nerves arise from the forebrain
and the brain stem.
I
II
I
II
III
Olfactory Telencephalon
Optic
Diencephalon
IV
VI
V
VII
VIII
IX
XII
XI
Cranial Nerves III through XII
arise from the Brain Stem:
Midbrain
III Oculomotor
IV Trochlear
Pons
V
Trigeminal
VI Abducens
VII Facial
Medulla
VIII Vestibulocochlear
IX Glossopharyngeal
X
Vagus
XII Hypoglossal
X
Cranial Nerve XI Spinal Accessory Nerve
arises from the Spinal Cord
2
A
c
Drawing A shows the ventral surface of a model of a dissected human
brain. The cerebral cortex with its underlying white matter
and the cerebellum have been removed.
In the forebrain the caudate (c) and putamen (p) join together
in the anterior, ventral area of the basal ganglia.
p
Cranial nerves:
B dorsal view
OPTIC II
c
OCULOMOTOR III
TROCHLEAR IV
midbrain
pons
medulla
spinal
cord
th
TRIGEMINAL V
ABDUCENS VI
FACIAL VII
VESTIBULOCOCHLEAR VIII
GLOSSOPHARYNGEAL IX
VAGUS X
HYPOGLOSSAL ROOTLETS XII
SPINAL ACCESSORY XI
Only the trochlear nerve IV
arises from the dorsal
surface of the brain stem.
It courses around the
midbrain to join III and VI to
enter the orbit.
3
Cranial Nerve Nuclei
The cranial nerves innervate the
head and neck,
Cranial nerve fibers include the same
four “general” functional components
as the spinal nerves :
GSE, GVE, GVA and GSA.
In addition the head contains 1) “special”
visceral sensory organs for olfaction and taste,
2) “special” somatic sensory organs for vision,
audition, and balance, and 3) a “special”
group of muscles embryologically derived
from the branchial arches.
Thus seven functionally-distinct columns of cells
in the brain stem comprise the cranial nerve nuclei:
GSE
GVE
SVE
GVA
SVA
GSA
SSA
somatic motor
preganglionic parasympathetic
branchial motor
visceral sensory
olfaction and taste
somatosensory
audition and vestibular function
The model shows
a “dissection” of the
cranial nerve nuclei
in the tegmentum of
the brain stem.
4
4
III
MOTOR NULCEI
IV
GSE
SOMATIC MOTOR
V
oculomotor III
extraocular mm.
trochlear
IV
abducens VI
hypoglossal XII tongue mm.
GVE
VII
VI
PARASYMPATHETIC
VII
IX
Edinger Westphal III (not on model)
salivatory nuclei VII, IX
dorsal motor nucleus of X
SVE
XII
X
BRANCHIOMOTOR
motor nuc. V mastication
facial nuc. VII facial expression
nucleus ambiguus IX, X, cXI
pharynx, larynx
accessory sXI
trapezius, sternomastoid
Nucleus ambiguus
IX, X and cXI
sXI
5 5
V mesencehaplic
SENSORY NULCEI
V principal
sensory
SSA AUDITION AND BALANCE
vestibular VIII
cochlear VIII
GSA
SOMATOSENSORY
trigeminal V:
mesencephalic proprioception
principal sensory discriminative touch
spinal pain & temperature
SVA
TASTE
nucleus solitarius,
rostral VII, IX, X
GVA
VIII vestibular
VIII cochlear
rost nuc solitarius
VII, IX, X
caud nuc solitarius
IX, X
V spinal
PAIN, etc.
nucleus solitarius
caudal IX, X
6 6
Cranial Nerves
and
Cranial Nerve Nuclei of the Brain Stem
F
Question I
Match each cranial nerve nucleus (A - H) with the
appropriate functional designation (1 - 8).
_____ 1. receives pain input from teeth
A
_____ 2. innervates pharyngeal mm.
B
_____ 3. receives input from inner ear
C
_____ 4. Innervates tongue mm.
D
G
H
I
_____ 5. receives fine tactile input from lips
E
_____ 6. Innervates mm. of mastication
_____ 7. preganglionic parasympathetic
_____ 8. Innervates extraocular mm.
77
Cranial Nerves and Cranial Nerve Nuclei of the Brain Stem
ANSWER SHEET
Question I
1.
2.
3.
4.
5.
6.
7.
8.
E
D
C
I
B
G
H
F
8