Cranial nerves IX X XI XII

Cranial nerves IX, X, XI, XII



The Glossopharyngeal Nerve (IX-th pair)
•A mixed nerve comprising the following fibres:

Somatic motor

Somatic sensitive

Visceral efferent

Viscerral afferent

Sensory fibers

•It exits the skull through the posterior foramen lacerum (jugular foramen) , together
with the vagus nerve, the accesory nerve and the internal jugular vein.




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, •Central motor neurons descend in the cortico-bulbar tract and sinapse bilaterally with
peripheric motor neurons in the rostral (superior) part of the ambiguous nucleus

•The axons of the neurons from the nucleus ambiguous (branchial motor fibers)

•The axons of the neurons from the ambiguus nucleus (motor branchial fibers) exit the
medulla between the olive and the inferior cerebellar peduncle

•Innervates the stylopharyngeus muscle which elevates the pharynx during swallowing
and speech.




Clinical Examination
Gag reflex:

-The patient is placed in front of a light source

-The posterior wall of the pharinx is touched with a minispatula

-The elevation of the posterior wall of the pharinx is noted, and the patient feels like
throwing up.

-In the case of a peripheral motor neuron lesion, the pharingian reflex will be diminished




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