Cranial Nerves Facial Flashcards
SVE
skeletal motor to facial expression muscles
SVA
taste sensation to anterior 2/3 tongue
GVE
parasymp to glands (lacrimal, nasal, palatine, submandibular sublingual)
GVA
sensory from nasal cavity, soft palate, adj pharyngeal wall
GSA
sensory from skin @ posterior ear, pinna, external auditory meatus
geniculate ganglion
swelling of facial n in facial canal
-sensory
-cell bodies of GSA, GVA, SVA
greater petrosal nerve
GVE, GVA
chorda tympani n
SVA, GVE
nerve of stapedius
SVE
prevents stapes from oscillating
exits cranial vault out of
stylomastoid foramen
lesion of preganglionic parasymps
to pterygopalatine gangila
gets regenerated and target is reached
lesion of preganglionic parasymps
to submandibular
crocodile tear syndrome
-when eating instead of salivating by sublingual and submand you cry bc axons go to pterygopalatine ganglion with chorda tympani
lesion is in facial canal (proximal to geniculate gang)
solitary tract
taste sensation processed at solitary nucleus
-carries SVA and GVA
projects to hypothalamus to mediate visceral resp to unpleasant stim aka vomit
UMN lesions are
purely MOTOR for corticonuclear tract
-nothing to do with sensory, parasymps
bell’s palsy
LMN lesion aka in the facial canal proximal (before)
-eyes, ear, mouth all affected (entire half of face ipsilateral to lesion)
-orbicularis oculi, stapes,
causes of bell’s palsy
viral infection of facial nerve in canal
-demyelination conduction block but can recover
dry eye from greater petrosal nerve (GVE)
hyperacusis from nerve to stapedius (SVE)
ear pain from geniculate ganglion
loss of taste from chorda tympani nerve
lesion distal stylomastoid foramen
mainly motor deficit ipsilateral
-sensory deficit to outer ear
middle cerebral A occlusion
lesion in lateral motor and sensory
-trunk, upper limb, face
contralateral
lenticulostriate A occulsion
supper ant and post limbs of internal capsule
-extensive and serious motor and sensory deficits since corticonuclear tracts course in genu
facial nucleus
for motor, has cell bodies of LMN
superior salivatory nucleus
for parasymps, has cell bodies of pregang parasymp for axons that synapse in pterygopalatine or submandibular ganglia
solitary nucleus
for sensory, receives central processes of SVA (taste) and GVA neurons
-shared with glossopharyngeal and vagus nerve
spinal tract of trigeminal
since facial, glosso, vagus not have pain nucleus of own it sends fibers of nociception (GSA) to spinal tract of V to terminate in pain nucleus
parts of corneal blink reflex
- afferent/sensory limb via ophthalamic of V (V1)
- efferent/motor via facial to orbicularis oculi
can either be direct (same side as stim) or consensual (resp on oppo side)
