1. CRANIAL NERVES II: BRANCHES OF IX
OUTLINE
I. GLOSSO-PHARYNGEAL NERVE
II. HITCHHIKING FIBERS
- review branches of IX
- pathways complicated by hitch-hiking fibers
IX - GLOSSO-
PHARYNGEAL

2. CRANIAL NERVE CHART: TYPES OF NEURONS
Somatic
Sensory
Visceral
Sensory
Taste,
Smell
Branchial
muscles
Autonomic X
VII, IX and X are complex and have a number of components

3. SVE - Special Visceral Efferents - Branchial Muscles
- motor to voluntary skeletal muscles derived from branchial arches
- visceral because develop in pharynx then migrate
Third
Glosso-
pharyngeal IX
First -
Trigeminal V
Second -
Facial
VII
Fourth
Vagus X
Sixth
Accessory XI

5. CRANIAL NERVES I. GVE PARASYMPATHETIC GANGLIA

6. GSA - General Somatic Afferents
sensory to skin, ORAL cavity, NASAL cavity, joints, muscles
ALMOST ALL TRIGEMINAL V EXCEPTION: SKIN OF OUTER EAR ALSO 1) VII- FACIAL 2) IX - GLOSSO-
PHARYNGEAL 3) X - VAGUS

7. GVA - General Visceral Afferents
Sensory to Pharynx and derivatives
All Pharynx is GVA
In 3 Cranial Nerves
Nasal
Cavity
GSA
NASOPHARYNX - VII
Oral Cavity
GSA
OROPHARYNX - IX
LARYNGOPHARYNX - X
IX – Also provides GVA touch to post. 1/3 of tongue

8. SVA - Special Visceral Afferents
Chemical Sense - TASTE - in three cranial nerves
X - VAGUS -
ant. to epiglottis
IX - GLOSSO-
PHARYNGEAL
post. 1/3 of tongue
VII - FACIAL -
ant. 2/3 of tongue
TONGUE
IX - SVA taste and
GVA touch to post. tongue

9. BRANCHES OF IX HITCHHIKE WITH BRANCHES OF V
Recall:
Recall:
Trigeminal V Receives hitchhiking fibers from Facial VII and Glossopharyngeal IX
CN XII Receives hitchhiking fibers from C1
example:
V3 Lingual
VII
Chorda
Tympani
Parasympathetics from IX also hitchhike with a branch of Trigeminal: Auriculotemporal nerve (V3)

10. PARASYMPATHETICS AND TASTE FIBERS OF VII AND IX JOIN BRANCHES OF V

11. IX - GLOSSOPHARYNGEAL IX
leaves Post. Cranial fossa via Jugular Foramen IX

12. IX - GLOSSOPHARYNGEAL IX exits via Jugular Foramen Lesser Petrosal N.
NOSE
exits via
Jugular Foramen
Lesser
Petrosal N.
Tympanic N.
1. Tympanic Nerve
Forms tympanic plexus; GVA sensory to middle ear
Mastoid sinus
auditory tube
Auditory
tube IX
2. Lesser Petrosal
GVE parasymp
To Parotid Gland
exits via
Jugular Foramen

13. IX- LESSER PETROSAL NERVE - PAROTID GLAND
IX Lesser Petrosal –synapse in Otic Ganglion
Post. ganglionic
parasymp. from Otic ganglion join Auriculo temporal N. V 3 -to Parotid Gland
May also carry GSA fibers to outer ear
Otic Ganglion
Auriculo
Temporal
N. V 3
Parotid Gland

14. IX - GLOSSOPHARYNGEAL 3. Carotid branches Sensory –
Motor Nerve to Stylopharyngeus
3. Carotid branches
Sensory –
Carotid sinus - blood Pressure
Carotid Body - CO2 in blood
4. Motor Nerve to Stylopharyngeus
5. Pharyngeal Branches
Sensory to oropharynx
6. Tonsillar Branches
Sensory to palatine tonsil
7. Lingual branches
Sensory (touch) & taste to post. 1/3 of tongue
Tympanic
Tonsillar
Lingual
Carotid
Pharyngeal br

16. IX – LESSER PARASYMPATHETIC OF IX JOIN BRANCHES OF V AURICULO-
TEMPORAL
NERVE
IX – LESSER
PETROSAL – OTIC
GANGLION

17. INTEGRATION REVIEW Carotid Pharyngeal branches IX – GAG REFLEX
IN - IX (Pharyngeal
Sensory branches)
OUT - X
IX –CENTRAL LESIONS –
Nucleus solitarius - GVA-- 9,10: cardiac-pulmonary areflexia; loss of chemo-baro-sensory afferents in the carotid sinus/body (Carotid branch IX)