CN VI Facial nerve Flashcards
Where does the facial nerve exit the skull?
stylomastoid foramen
what does the facial nerve motor innervate?
muscles of facial expression
stapedius
posterior belly digastric
what are some sensory innervations of facial nerve?
small area of skin near external auditory meatus
what special sensory innervations does facial nerve provide?
TASTE anterior 2/3 tongue (chorda tympani)
where is the facial nerve nucleus?
pons
fascicles rap around abducens nerve before exiting the PONTOMEDULLARY JUNCTION
what is the intracranial course of the facial nerve?
posterior cranial fossa crosses through petrous portion of the temporal bone (near CN8+ear) passes through the internal acoustic meatus where it SPLITS
where does the each side of facial nerve go after it splits at the genu?
pterygopalatine ganglion
submandibular ganglion/out to facial muscles
where does the LMN for CN 7 emerge?
pontomedullary junction
where do the UMN for facial nerve emerge?
from the precentral gyrus or primary motor cortex
what is the path of UMN projections for the facial nerve?
UMN projections, corona radiata, internal capsule, CN VII nucleus (septate ones for upper and lower face)
UMP to nuclei for upper face have what type of projection?
bilateral
UMP to nuclei for lower face have what type of projection?
contralateral
what happens to the forehead of someone with an UMP supranuclear lesion?
forehead is spared
what happens to the forehead of someone with an UMP intranuclear lesion?
facial drooping on ipsilateral side
what parasympathetic innervations does the facial nerve supply?
secretomotor to salivary glands (sub mandibular and lingual)
palatine, nasal and lacrimal glands
for the autonomic NS where are the preganglionic fibers?
cell bodies n the brainstem or sacral spinal cord
for the autonomic NS where are the postganglionic fibers?
effector organ
what is the path pr preganglionic parasympathetics pathways?
PMJ, posterior cranial fossa, internal acoustic meatus, into facial canal where split to greater petrosal (pterygopalatine gang, and chorda tympani to SMG)
where do postganglionic fibers from the pterygopalatine ganglion go?
lacrimal, nasal, and palatine glands
(courses over V2 and V1 as goes to lacrimal gland)
where do postganglionic fibers from the submandibular ganglion go?
submandibular and sublingual glands
be sure to practice lesions
def gonna be lot of case study questions
