1: UIII CN#VII Flashcards
What is the name of CN# VII?
Facial Nerve
What does the facial nerve carry?
motor and sensory fibers MIXED
What is the nickname of CN# VII?
Nerve of Facial Expression
What does the facial nerve supply?
many facial muscles
What is the primary nucleus of origin for CN# VII?
Motor nucleus of the facial nerve
What does the superior salivary nucleus contribute to the facial nerve?
preganglionic parasympathetic fibers
Where do the sensory fibers of the facial nerve terminate?
in the upper part of the solitary nucleus
What are other names for the solitary nucleus?
tractus solitarius, solitary nucleus
Where are the cell bodies of the sensory neurons of CN# VII?
geniculate ganglion
What type of information is carried to the geniculate ganglion and then to the solitary nucleus?
general sensation from the external ear and lateral tympanic membrane
Taste info also
What are the specific fibers that carry taste from the anterior part of the tongue?
chorda tympani
How do the fibers reach the muscles of facial expression?
LMN’s from the motor nucleus exit the CNS, travel TROUGH the geniculate ganglion to the muscles
Where does the motor nucleus of the facial nerve recieve fibers from?
both cerebral hemispheres
Where does the nucleus supplying the muscle inferior to the part of the face receive info from?
ONLY the contralateral cortex
What other area does the motor nucleus receive info from?
reticular formation
Where do preganglionic parasympathetic fibers from the superior salivary nucleus synapse?
either pterygoid ganglion or submandibular ganglion
What do the postganglionic fibers of the facial nerve supply?
lacrimal gland, submandubular gland, small glands of the oral and nasal cavity
What is the apparent origin of the facial nerve?
laterally in the sulcus btwn pons and the MO
medullopontein sulcus
How do fibers from the motor nucleus travel before exiting the CNS?
posteriorly and arch around the abducens nucleus
What are the two roots present at the apparent origin of the facial nerve?
motor root (facial nerve proper) intermediate nerve (sensory and parasympathetic)
After exiting the CNS, how do both roots travel together?
enter the internal acoustic meatus in the petrous part of the temporal bone
Where is the geniculate ganglion found?
in the facial canal near the external genu of the facial nerve
What enters the facial canal and forms the external genu of the facial nerve?
the motor root and intermediate root, blending posteriorly
What are the three nerves given off in the facial canal?
greater petrosal nerve
nerve to the stapedius
chorda tympani
How does the greater petrosal nerve travel?
comes off the geniculate ganglion, travels anteriorward through the hiatus for the greater petrosal nerve.
reenters the petrous part of the temporal bone through the foramen lucerum, travels in the pterygoid canal and then joins the pterygopalatine ganglion
What type of fibers does the greater petrosal nerve carry?
preganglionic parasympathetic fibers
What does the greater petrosal nerve stimulate?
secretions from the lacrimal, nasal, and palatal glands
What is another name for the greater petrosal nerve?
superficial petrosal nerve
What is the second nerve given off in the facial canal?
nerve to the stapedius
What kind of fibers does the nerve to the stapedius carry?
motor only
What does the nerve to the stapedius supply?
the stapedius muscle of the middle ear
What is the function of the stapedius muscle?
stabilizes the stapedius, protects from loud noises
What is the third branch coming off of the facial nerve in the facial canal?
chorda tympani
What does the chorda tympani carry?
preganglionic parasympathetic fibers and taste fibers
What is the course of the chorda tympani?
traverses the tympanic cavity and leaves the temporal bone through the pterygopalatic fissure. combines with the lingual nerve
T/F: the chorda tympani carries two way traffic?
true
