CN9 Glossopharyngeal nerve

Question 1

What is cranial nerve 9?

Answer 1

Glossopharyngeal nerve

Question 2

What is the route of the CN9 glossopharyngeal nerve from its origin to its innervation?

Answer 2

Passes through jugular foramen
to parts of oral cavity, pharynx, tongue, ear
descends down neck to carotid arteries

Question 3

What are the functions of the CN9 glossopharyngeal nerve?

Answer 3

General sensory - soft palate, tonsils, oropharynx, middle ear, tympanic membrane, carotid body, carotid sinus, posterior third of tongue

Special sensory - taste of posterior third of tongue

Autonomic parasympathetic - parotid gland

Motor - stylopharyngeus muscle

Question 4

What is the action of the stylopharyngeus muscle?

Answer 4

Role in swallowing

Question 5

How are the functions of the CN9 glossopharyngeal nerve tested?

Answer 5

Gag reflex

Question 6

What is the gag reflex?

Answer 6

Sensation at back of throat

causes rethcing

Question 7

What are the nerves involved in the gag reflex?

Answer 7

Afferent - CN9 glossopharyngeal nerve

Efferent - vagus nerve