Cranial Nerve Lecture Flashcards
sensory innervation of anterior 2/3 of tongue
lingual n.
general sensation and taste innervation of posterior 1/3 of tongue
glossopharyngeal n.
CN VII somatic motor component
internal acoustic meatus –> emerges from stylomastoid foramen
innervates facial muscles + stylohyoid, posterior belly of digastric, stapedius
CN VII parasympathetic component
- intermediate n. –> internal acoustic meatus –> facial canal –> greater petrosal n. –> vidian canal –> pterygopalatine ganglion –> glands in eye, nose, palate
- intermediate n. –> chorda tympani (exits petrotympanic fissure, travels along V3 lingual n, synapses in submandibular ganglion, innervates submandibular and sublingual salivary glands)
CN VII special sensory component
taste fibers return from anterior 2/3 of tongue
traveling back through petrotympanic fissure
encounter geniculate ganglion and return to CNS
taste buds –> lingual n –> [petrotympanic fissure] –> chorda tympani –> geniculate ganglion –> CNS
CN V somatic sensory component
from trigeminal ganglion
V1 –> ophthalmic division [superior orbital fissure –> supraorbital foramen]
-nasal cavity, paranasal sinuses, meninges
V2 –> maxillary division [foramen rotundum –> infraorbital foramen]
-nasal cavity, paranasal sinuses, maxillary teeth, oral mucosa
V3 –> mandibular division [foramen ovale –> mental foramen]
-tongue (ant 2/3), lower teeth, oral mucosa, external tympanic membrane, buccal mucosa, meninges
Sensory to most of dura mater
CN V somatic motor component
V3 (mandibular division) –>
4 m. of mastication
(temporalis, masseter, medial/lateral pterygoid)
4 accessory n. of mastication
(tensor tympani, myelohyoid, ant belly of digastric, tensor veli palatini)
CN IX somatic motor component
thru jugular foramen to stylopharyngeus m.
CN IX somatic sensory component
thru jugular foramen to back of pharynx (gag reflex)
CN IX visceral sensory component
thru juglar foramen to carotid body/carotid sinus
CN IX special sensory component
thru jugular foreman to posterior 1/3 of tongue
taste and general sensory
CN IX visceral motor component
thru jugular foramen –> tympanic canaliculus “tympanic n.” –> forms plexus in middle ear –> emerges as LESSER PETROSAL N.
thru foramen ovale –> synapses on OTIC ganglion –> postganglionic fibers of lesser petrosal n. piggyback on AURICULOTEMPORAL n. (V3) –> jump off to supply PAROTID gland
CN III somatic motor component
oculomotor nucleus –> orbit –> split to sup/inf divisions –> supply 5 of 7 extraocular m.
superior rectus inferior rectus medial rectus inferior oblique levator palpebrae superioris
CN III visceral motor component
accessory oculomotor nucleus –> orbit –> inferior division CN III –> ciliary ganglion –> supply ciliary m. and sphincter pupillae
CN X visceral motor component
jugular foramen --> to glands and smooth muscle in... larynx pharynx esophagus abd viscera
CN X somatic motor component
jugular foramen –> to…
pharyngeal constrictors
laryngeal m.
palatal m.
CN X special sensory component
jugular foramen –> to epiglottis (taste buds)
CN X somatic sensory component
jugular foramen –> to…
ear/canal
LARYNX (via superior/recurrent laryngeal n.)
dura
CN I
olfactory n.
special sensory only.
does NOT originate in brain stem.
originates in nose.
olfactory axons –> cribriform plate –> synapse on olfactory bulb of olfactory tract
olfactory tract
extension of the brain.
covered by meninges.
CN II
optic n. (extension of brain, covered by meninges)
light stim retina –> APs travel down optic n. –> some cross at optic chiasm, others don’t –> travel down “optic TRACT” –> occipital lobe for interpretation by visual cortex
optic n. vs optic tract
globe –> chiasm = optic n.
posterior to chiasm = optic tract
axons of retinal ganglion cells make up the
optic n.
CN IV
trochlear n.
somatic motor only.
devoted to one m. in eye (superior oblique m.)
