Exam 2: Unit IV: CN IX, X Flashcards
What type of fibers does the Glossopharyngeal Nerve carry?
(CN IX) –mixed
- Motor
- general/somatic Sensory
- visceral sensory
- special sensory
- preganglionic parasympathetic
What type of sensory does CN IX carry?
- General sensory
- Special sensory–> taste
- Visceral sensory
What muscle(s) does the Glossopharyngeal nerve supply?
stylopharyngeus muscle
What is the nucleus of origin for the Glossopharyngeal nerve (CN IX)?
superior part of the nucleus ambiguus (recall CN X and XI also get info from here)
Where do the preganglionic parasympathetic fibers of the Glossopharyngeal nerve arise from?
inferior salivary nucleus
recall: sup. salivary nucleus had fibers go into CN VII
What are the nuclei of termination of the Glossopharyngeal nerve?
solitary nucleus (recall: CN VII also had info go here)–> taste(sup.) and visceral sensory(inf.)
spinal nucleus of trigeminal–> pain and temp.
What are the peripheral ganglion associate with the Glossopharyngeal nerve? Which is smaller?
- superior ganglion (smaller and usually thought of as a separated part of inf. ganglion)
- inferior ganglion (petrosal ganglion)
What type of general sensory info does the Glossopharyngeal nerve carry?
- nasopharynx, oropharynx
- posterior 1/3 of tongue
- uvula
- palatine tonsils
- tympanic cavity
Where are the cell bodies located that carry the general sensory info for the Glossopharyngeal nerve? Where do their axons go?
in the inferior ganglion (so does taste info); go to spinal nucleus of the trigeminal nerve (therefore carry pain and temp)
What taste information does the Glossopharyngeal nerve carry? Where are their cell bodies located? Where do they do synapse?
posterior 1/3 of tongue, posterior to sulcus terminalis; cell bodies in inferior ganglion; synapse in superior part of solitary nucleus
What nucleus does the taste information carried in CN IX synapse?
superior part of solitary nucleus (taste in CN VII also synapses in solitary nucleus)
The visceral afferent information carried in the Glossopharyngeal nerve will have cell bodies in what ganglion and will synapse in what nucleus? Where is the information coming from?
inferior ganglion
inferior part of the solitary nucleus
carotid sinus and carotid body
What is the nucleus of origin for the Glossopharyngeal Nerve?
Nucleus ambiguus (same for CN IX, X, XI)
Where does the tympanic plexus carry somatosensory information from?
- tympanic cavity
- pharyngotympanic tube
- mastoid air cells
What type of neurons are carried from the nucleus ambiguus in CN IX? What muscle do they supply?
lower motor neurons; to stylopharngeus muscle
Describe the pathway of the parasympathetic fibers carried in the Glossopharyngeal nerve.
inferior salivary nucleus gives rise to preganglionic parasympathetic axons –> carried in CN IX –> synpase in otic ganglion–> give rise to postganglionic parasym. fibers –> supply parotid gland, buccal glands, and inferior labial glands
What does the parasympathetic pathway of the Glossopharyngeal nerve supply?
- parotid gland
- buccal glands
- inferior labial glands
What is the apparent origin of the Glossopharyngeal nerve?
series of rootlets arise from the lateral, superior aspect of the medullar oblongata
Where does CN IX exit the skull?
Glossopharyngeal N. exits via the jugular foramen
Where is the superior ganglion ass. with CN IX located? Where is the inferior ganglion located?
sup. gang. –> inside the cranium
inf. gang. –> beyond the jugular foramen, outside of the cranium
How many branches does the Glossopharyngeal nerve have and what are they?
6 branches
- Tympanic nerve (S, parasym.)
- Carotid Branch (visceral S)
- Pharyngeal Branch (S)
- Muscular branch (M)
- Tonsillar Branch (S)
- Lingual Branch (S, and special S-taste)
Where does the tympanic nerve arise from (branch of CN IX) and what does it carry?
inferior ganglion; carries preganglionic parasym. fibers and sensory fibers
Where are the fibers carried through in the tympanic nerve (branch of CN IX) carried through?
tympanic canaliculus into the tympanic cavity
What does the tympanic nerve of CN IX receive once it is in the tympanic cavity? What is formed once this occurs?
postganglionic sympathetic fibers from the superior cervical ganglion
forms tympanic plexus
What fibers are ending the tympanic plexus (ass. with tympanic n, branch of CN IX) and what fibers pass through it?
sensory and postganglionic symp. fibers end in this plexus
preganglionic parasympethetic fibers pass THROUGH it
What fibers are passing through the tympanic plexus? Once they do pass through what is there name changed to?
preganglionic parasympathetic fibers carried in Tympanic N (branch of CN IX); once pass through tympanic plexus they reform as “Lesser Petrosal Nerve”
The fibers leaving the tympanic plexus are called what? Where do they travel? (ass. with CN IX)
lesser petrosal nerve and travel through lesser petrosal canal to otic ganglion
How are the postganglionic parasymathetic fibers that arise from the otic ganglion carried?
carried in branches of CN V3 to the parotid, buccal, and inf. labial glands
What type of information does the carotid branch of CN IX carry? Where does this branch come from and where does it enter CN IX?
afferent info from chemoreceptors in carotid body and baroreceptors in carotid sinus
ascends from below and enters CN IX at inf. ganglion
What type of info does the pharyngeal branches of CN IX carry? What other branches do they combined with?
info from mucosa of pharynx (general sensory)
combines with some Vagal (CN X) branches –> to form pharyngeal plexus near middle pharyngeal plexus
What does the muscular branch of CN IX supply?
one muscle–> stylopharyngeus
recall, fibers arised from nucleus ambiguus
After the branches (Tympanic, Carotid, Pharyngeal, Muscular) of the Glossopharyngeal nerve connect to CN IX, where are the remaining two branches reaching?
oral cavity
- Tonsillar Branch
- Lingual Branch
What does the Tonsillar branch of CN IX carry?
general sensory info from palatine tonsils and oral mucosa
What info does the Lingual branch of CN IX carry?
general sensory AND taste info from posterior 1/3 of the tongue (post. to sulcus terminalis)
What CN is known as the “wonderer”?
Vagus Nerve (CN X)
What type of fibers does the Vagus Nerve carry?
“mixed”
- motor
- general/ somatic sensory
- visceral sensory
- special sensory
- parasympathetic
What is the longest CN?
Vagus nerve
What is the most important parasympathetic nerve in the body?
Vagus nerve