Students should have a thorough knowledge about the various functional components of cranial nerve(s) nuclei. Students should be able to identify the exact locations of the cranial nerve nuclei and the origin and exits of cranial nerves . Students should be able to explain the Course, Branches and functions of all cranial nerves. Students should be Describe the dysfunctions associated with lesions of each cranial nerve. Sensory cranial nerves: contain only afferent (sensory) fibers Ⅰ Olfactory nerve Ⅱ Optic nerve Ⅷ Vestibulocochlear nerve Motor cranial nerves: contain only efferent (motor) fibers Ⅲ Oculomotor nerve Ⅳ Trochlear nerve Ⅵ Abducent nerve Ⅺ Spinal Accessory nerve Ⅻ Hypoglossal nerve Mixed nerves: contain both sensory and motor fibers Ⅴ Trigeminal nerve, Ⅶ Facial nerve, Ⅸ Glossopharyngeal nerve Ⅹ Vagus nerve

1. CRANIAL NERVES
1. Students should have a thorough knowledge about the
various functional components of cranial nerve(s) nuclei.
2. Students should be able to identify the exact locations of
the cranial nerve nuclei and the origin and exits of cranial
nerves .
3. Students should be able to explain the Course, Branches
and functions of all cranial nerves.
4. Students should be Describe the dysfunctions associated
with lesions of each cranial nerve.
LEARNING OBJECTIVES:

2. 12 PAIRS OF CRANIAL NERVES
Ⅰ Olfactory nerve
Ⅱ Optic nerve
Ⅲ Oculomotor nerve
Ⅳ Trochlear nerve
Ⅴ Trigeminal nerve
Ⅵ Abducent nerve
Ⅶ Facial nerve
Ⅷ Vestibulocochlear nerve
Ⅸ Glossopharyngeal nerve
Ⅹ Vagus nerve
Ⅺ Accessory nerve
Ⅻ Hypoglossal nerve

3. CLASSIFICATION
• Sensory cranial nerves: contain only afferent (sensory) fibers
• Ⅰ Olfactory nerve
• Ⅱ Optic nerve
• Ⅷ Vestibulocochlear nerve
• Motor cranial nerves: contain only efferent (motor) fibers
• Ⅲ Oculomotor nerve
• Ⅳ Trochlear nerve
• Ⅵ Abducent nerve
• Ⅺ Spinal Accessory nerve
• Ⅻ Hypoglossal nerve
• Mixed nerves: contain both sensory and motor fibers
• Ⅴ Trigeminal nerve,
• Ⅶ Facial nerve,
• Ⅸ Glossopharyngeal nerve
• Ⅹ Vagus nerve

4. SUBDIVISIONS OF VERTICAL
COLUMNS
• Motor nuclei
• Somatic motor
• closest to midline
• eyes, tongue
• CN III, IV, VI, XII
• Branchial motor
• Lateral position
• Branchial arches: chewing,
expression, middle ear,
pharynx, larynx,
sternomastoic, trapezius
• CN V, VII, XI
• N. ambiguus (IX, X)
• Visceral motor
• ventral / ventrolateral
• Parasympathetic: glands,
smooth muscle, heart,
lungs, GI above splenic
flexure
• Edinger-Westfall (III)
• Sup. & Inf. salivatory (VII)
• Dorsal motor nucleus of X
• Sensory nuclei
• General (Somato) sensory
• lateral to branchial motor
• Face, sinuses, meninges
• All modalities
• CN V mainly
• Also CN VII, IX, X
• Visceral sensory (General and
Special)
• lateral to visceral motor
• Taste; cardiorespiratory, GI info
• N. of the solitary tract (CN VII,
IX, X)
• Special sensory
• furthest lateral
• Balance; hearing
• CN VIII (vestibular)
• CN VIII (cochlear)

6. BRAINSTEM /
FUNCTIONAL
COMPONENTS
GSE SVE GVE GVA SVA GSA SSA
MIDBRAIN
III CN
(Motor
Nucleus)
III CN
(Edinger
Westphal
Nucleus)
IV CN
(Motor
Nucleus)
PONS
VI CN
(Motor
Nucleus)
V CN
(Motor Nucleus) VII CN
(Superior
SalivatoryNuc
leus)
VII CN
(Motor Nucleus)
MEDULLA
OBLONGATA
XII CN
(Hypoglossal
Nucleus)
IX, X & XI CN
(Nucleus
Ambiguus)
IX CN
(Inferior
Salivatory
Nucleus)
X CN
(Dorsal Motor
Nucleus)
VII
CN
IX
CN
X
CN
IX
CN
X
CN
V
CN
V
CN
V
CN
IX
CN
X
CN
VIII
CN
VII
CN
VII
CN
Nucleus Tractus
Solitarius

7. FUNCTIONAL COMPONENTS
• General somatic afferent fibers (GSA): exteroceptive
and proprioceptive impulses from head and face to
somatic sensory nuclei
• Special somatic afferent fibers (SSA): sensory impulses
from special sense organs of vision, equilibrium and
hearing to the brain
• General visceral afferent fibers (GVA): interoceptive
impulses from the viscera to the visceral sensory nuclei
• Special visceral afferent fibers (SVA):
sensory impulses from special sense organs of smell
and taste.

8. • General somatic efferent fibers (GSE): innervate skeletal muscles of
eye and tongue
• Special visceral efferent fibers (SVE): transmit motor impulses from
the brain to skeletal muscles derived from branchial arches (muscles of
mastication, facial expression and swallowing)
• General visceral efferent fibers (GVE): transmit motor impulses from
the general visceral motor nuclei and relayed in parasympathetic
ganglions (cardiac muscles，smooth muscles and glands)
FUNCTIONAL COMPONENTS

9. CRANIAL NERVE -
I

10. CRIBIFORMPLATE
SENSORY=
Name: Olfactory nerve
Foramen: Cribiform plate
Fiber Type: Special sensory
Function: Olfactory bulbs, Smell
Branches: Olfactory filaments
Embryo: CNS (ectoderm)
OLFACTORY NERVE

11. • Function: Special sensory (special visceral
afferent)
• The cell bodies of olfactory receptor neurons are
located in the olfactory organ (the olfactory part of
the nasal mucosa or olfactory area), which is
located in the roof of the nasal cavity and along
the nasal septum and medial wall of the superior
nasal concha.
• The apical surfaces of the neurons possess fine
olfactory cilia, bathed by a film of watery
mucus secreted by the olfactory glands of the
epithelium. The cilia are stimulated by molecules
of an odiferous gas dissolved in the fluid.
OLFACTORY NERVE

12. Olfactory bulb
Olfactory tract
Anterior perforated
substance
Uncus
Bypass thalamus and goes directly into the
taste area
Nerve filaments
Cribriform plate of
ethmoid bone
OLFACTORY NERVE

14. Receptors and the first neurons

15. Olfactory Pathways

16. Olfactory Bulb

17. Fourth neurons

18. Olfactory Pathways

22. Purpose of Test

27. The End
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