Unit III - C.N.VII - Facial Nerve Flashcards
What type of fibers does the facial nerve carry?
Motor and sensory
Because it carries both sensory and motor fibers it is considered what type of nerve?
mixed
What is the facial nerve known as?
“Nerve of facial expression”
What types of sensory does it have?
Special and general sensory
What type of special sensory does facial nerve have?
Taste
What is the primary nucleus of origin for the facial nerve?
Motor nucleus of the facial nerve
What other nucleus contributes fibers to the facial nerve?
Superior salivary nucleus
What types of fibers does the superior salivary nucleus contribute to the facial nerve?
Preganglionic parasympathetic fibers
Sensory fibers carried in the facial nerve terminate where?
Upper part of the solitary nucleus
Where are the cell bodies of the sensory (both special and general) neurons found?
Geniculate ganglion
Sensory pathway - General sensation from what is carried to the geniculate ganglion?
External ear and
Lateral tympanic membrane
Axons from the external ear and lateral tympanic membrane carry information to where?
Solitary nucleus
Taste information also travels thought neurons with cell bodies found in the ________ and terminates in the _______.
Geniculate ganglion
Solitary nucleus
Specific fibers that convey taste from the _________ are carried in the ________.
Anterior part of the tongue
Chorda tympani
Axons from _____ in the motor nucleus of the facial nerve exit the CNS, travel through the _______ and innervate the muscle of _______.
LMN
Geniculate ganglion
Facial expression
The motor nucleus of the facial nerve receives information from ________.
Both cerebral hemispheres
The part of the nucleus supplying muscle in the inferior part of the face receives information from?
ONLY the contralateral cortex
The motor nucleus also receives information from the?
Reticular formation
Preganglionic parasympathetic fibers from the superior salivary nucleus synapse in either the ______ or the ______.
Pterygopalatine ganglion
submandibular ganglion
Postganglionic fibers supply the _______, ______, and _____ glands, as well as small glands in the ____ and _____ cavities.
Lacrimal
Submandibular
Sublingual
Oral and nasal cavities
Where is the apparent origin of the facial nerve?
Laterally in the sulcus between pons and M.O.
Before exiting the CNS, fibers from the motor nucleus first travel _______ and arch around the ______.
posteriorly
Abducens nucleus
What two roots are present at the apparent origin?
Motor root (facial nerve proper) intermediate nerve/root:
The intermediate root present at the apparent origin carries what type of fibers?
Sensory and parasympathetic
Upon exiting the CNS, both roots travel _______ and enter the ____________, located in the _______.
Together
Internal acoustic meats
Patrons part of the temporal bone
After entering the internal acoustic meats, the roots _______, and enter the _____ and then bend posteriorly, forming the __________ of the facial nerve
combine to form a single trunk
Facial canal
External genu
Where is the geniculate ganglion located?
In the external genu of facial canal
What three nerves are given off in the facial canal?
Greater petrosal nerve
Nerve to the stapedius
Chorda tympani
When the greater petrosal nerve comes off of the geniculate ganglion, it travels anteriorward through what?
The hiatus for the greater petrosal nerve
The greater petrosal nerve re-enters the petrous part of the temporal bone through what opening?
Foramen lacerum
After entering the foramen lacerum, the greater petrosal nerve travels in the _________ and ultimately joins the ________.
pterygoid canal
Pterygopalatine ganglion
The greater petrosal nerve carries what type of fibers?
Preganglionic parasympathetic fibers
The preganglionic parasympathetic fibers of the greater petrosal nerves stimulate secretions of what glands?
Lacrimal
Nasal
palatal
The greater petrosal nerve also is called?
The superficial petrosal nerve
What is the second nerve given off by the facial nerve?
Nerve to the stapedius
Where is the nerve to the stapedius give off?
In the facial canal
What does the nerve to the stapedius supply?
Stapedius muscle of the middle ear
What is special about the stapedius?
Smallest muscle in the body
What does the stapedius muscle do?
Stabilizes the shapes, providing protection of loud noises
What is the third branch coming off of the facial nerve in the facial canal?
Chorda tympani
What types of fibers does the chorda tympani fibers carry?
Preganglionic parasympathetic fibers and taste fibers
Chorda tympanic traverses what?
The tympanic cavity
The chords tympanic leaves the temporal bone through what?
pterygotympanic fissure
After leaving the pterygotympanic fissure, the chorda tympani nerve combine with which nerve?
Lingual nerve
The lingual nerve is a branch of what division of the trigeminal nerve?
Mandibular
All remaining fibers after the three branches are given off are what type in nature?
Motor and somatosensory
The remaining fibers after the three branches are given off exit temporal bone through what?
They stylomastoid foramen
What are the three branches given off the facial btw the stylomastoid foremen and the parotid gland?
digastric branch
stylohyoid branch
Posterior articular nerve
The digastric branch supplies what?
The superior belly of the digastric muscle
The stylohyoid branch supplies what?
The stylohyoid muscle
The posterior auricular nerve travel where?
Posterior to the ear
The posterior auricular nerve divides into what two branches?
Occipital branch
auricular branch
Occipital branch supplies what?
Occipital muscle
Auricular branch supplies what?
Posterior auricular muscle
Intrinsic muscles of anterior part of ear
After it gives off the fibers, again, it travels into which area?
The parotid gland
In the parotid gland the facial nerve forms what?
The parotid plexus
In the parotid gland, the plexus gives rise to two trunks:
temporofacial
cervicofacial
From these two trunks rise to these five branches
Temporal branch Zygomatic branch buccal branch Marginal branch Cervical branch
These branches supply what?
Muscles of facial expression
Temporal branch supplies what?
Intrinsic auricular muscles
Superior auricular muscles
Anterior auricular muscles
In combination with the zygomaticotemporal (V2) and auriculotemporal (V3), they supply these muscles:
orbicularis oculi, corrugator supercili, and frontal belly of the occipitofrontalis
Zygomatic branches help supply which muscle?
Orbicularis muscle
Buccal branches supply several muscles including what?
buccinators, orbicularis oris, and levator anguli oris
The cervical branch travels inferiorly to supply what?
platysma
What is Bell’s Palsy?
Paralysis of facial nerve. Flaccidity of muscles on same side
What is superficial partidectomy?
Surgical removal of the parotid gland.
What can happen in a superficial parotidectomy?
May cut facial nerve and auriculotemporal (CN 5) and facial muscles will be affected.
