Cranial Nerves Flashcards
(11 cards)
CN:
CN receive from what (from + gyrus) > 1 > 1 > 1 (+fiber) > synapse (2)
(B) except (2)
parasympathetic - GSE (4) GVE (4) SVE (5), function (1.2.1), receive (2), forms what
sensory - GSA (3) SSA (2) GVA (2) SVA (4), function (1.1.1.2), journey (2) > 2nd order > 3rd > tract
CN receives from corticobulbar fibers of pyramidal cells (precentral gyrus) -> corona radiata > internal capsule > basis pedunculi of midbrain (has corticospinal fibers) > synapse with interneuron or directly with CN
(B) except CN7&12
PARASYMPATHETIC
- GSE (3 4 6 12) = striated muscles
- GVE (3 7 9 10) = smooth muscles, glands
- SVE (5 7 9 10 11) = branchial striated
- forms cranial outflow of parasympathetic of ANS
- receive from cortex & hypothalamus
SENSORY
- GSA (5 9 10) = general sensations
- SSA (2 8) = hearing, balance
- GVA (9 10) = visceral
- SVA (1 7 9 10) = smell, taste
- journey: sensory ganglia (in nerve trunk) or sensory organ (eye ear nose) as 1st order neuron -> 2nd order from CN nuclei -> 3rd order in VPM of parietal (trigeminothalamic tract)
CN: Olfactory Nerve
myelin, cover
receptor, hair (from + for), nerve fiber (from + to)
bulb - fibers synapse with what = what
tract - divide where, ipsi/contra, med vs. lat striae
primary vs. secondary area - name, #, where (1.1), for
- unmyelinated, covered by schwann cells
- receptor: olfactory mucous membrane
- olfactory hair: from coarse peripheral fibers, for air odor
- nerve fiber: from fine central fibers, to bulb
- olfactory bulb: nerve fiber synapse with dendrites of mitral cells = synaptic glomeruli
olfactory tract
- divide at ant perforated substance; to contralateral
- medial striae: to bulb
- lateral striae: to cortex
cortex
- primary/periamygdaloid/prepiform: in uncus
- entorhinal/28: in parahippocampus; for appreciation
CN: Optic Nerve
myelin, cover, pathway (6), receptor (2)
- chiasm: where, ant (1) pos (1)
- tract: where, synapse (3)
(R) FOV: temporal/nasal, FOV ipsi/contra cortex
clinical- monocular, homonymous, heteronymous, leisure at occipital vs. nerve
- myelinated, covered with oligodendrocytes
- pathway: nerve > chiasm > tract > LGB > radiation > cortex
- receptor: rods (b&w), cones (color)
- optic chiasm: at 3rd ventricle; ant goes with nerve, pos with tract
- optic tract: at cerebral peduncle; synapse with pretectal nucleus, LGB, sup colliculus
- (R) FOV = right nasal left temporal
- FOV goes to contralateral cortex
CLINICAL
- monocular: none at eye
- homonymous: no temporal & nasal; d/t tract or radiation
- heteronymous/bitemporal: d/t chiasm d/t enlarged pituirary; no temporals
- lesion at occipital = blind, with light
- lesion at nerve = blind, no light
CN: Optic Nerve - Reflexes
light reflex
- afferent: (3) > synapse > synapse > end
- efferent: via (1) to (2)
accommodation reflex
- contract = 1 = 1
- afferent: (3) > synapse > (1) > end
- efferent: start + fiber > synapse > (1) > end (2)
corneal
- afferent & efferent
visual body
- what/for
- (3) > synapse > tract (2) > (1)
pupillary skin
- afferent & efferent ending (1.2)
LIGHT REFLEX
- afferent: nerve chiasm tract -> synapse with pretectal nuclei -> synapse with edinger-westphal -> end at ciliary ganglion
- efferent: via short ciliary nerves & constrictor pupillae of iris
ACCOMMODATION REFLEX
- contract constrictor = thicker lens = inc refraction
- afferent: nerve chiasm tract -> synapse with LGB -> radiation -> cortex
- efferent: start at cortex as corticonuclear fibers -> synapse with edinger-westphal -> ciliary ganglion -> short ciliary nerve & constrictor pupillae
CORNEAL REFLEX (A: CN5, E: CN7)
VISUAL BODY
- move eyes/protect eyes from oncoming
- nerve chiasm tract -> synapse with sup colliculi -> tectobulbar & tectospinal tract -> CN motor nuclei
PUPILLARY SKIN
- response to pain
- afferent end at cervical sympathetic ganglion, efferent end at long & short cilliary nerve & dilator pupillae muscle
CN: Olfactory Nerve
nucleus - receive (2), supplies (1)
edinger - receive (2), supplies (1)
enter cavity via what
clinical - strabismus, opthalmoplegia (2)
main oculomotor nucleus
- receive: corticonuclear, tectobulbar
- supplies: extrinsic
edinger-westphal
- receive: corticonuclear, pretectal
- supplies: intrinsic
enters cavity via SOF
CLINICAL
- external strabismus: go lat
- internal ophthalmoplegia: no autonomic yes EOM = undilated
- external ophthalmoplegia: yes autonomic no EOM = one eye abducted
CN: Trochlear & Abducens Nerve
TROCHLEAR NERVE
- ant/pos, muscle, receive (2)
ABDUCENS NERVE
- muscle, receive (2)
- strabismus, internuclear opthalmoplegia sx
TROCHLEAR NERVE
- only nerve exiting posteriorly
- sup oblique muscle
- receive: corticonuclear, tectobulbar
ABDUCENS NERVE
- lat rectus
- receive: corticonuclear, tectobulbar
- internal strabismus: go in
- internuclear ophthalmoplegia: only one lat rectus contracts
CN: Trigeminal Nerve
mesencephalic - polar, where
ascending vs. descending terminate where
ganglion (where)
spinal nucleus x 3 branches
motor nucleus - where, receive (4), muscle (3)
pathway - leaves where as med/lat small/big > fossa to fossa > (1) = (3)
- main sensory nuclei: at pons; cont with spinal nucleus
- mesencephalic nucleus: unipolar, at aqueduct
- ascending terminate at sensory, descending at spinal
- spinal nucleus: ophthalmic at inferior, maxillary at mid, mandibular at sup
- semilunar/trigeminal ganglion: at trigeminal/meckel cave
motor nucleus
- in pons
- receive: corticonuclear, RF, red nucleus, tectum
- muscle: mastication, tympani, ant belly of digastric, mylohyoid
pathway
- leaves pons as smaller medial motor & larger lateral sensory -> pos cranial fossa to mid cranial fossa -> trigeminal ganglion -> CN5 branches
CN: Facial Nerve
where
main motor - where, receive (1)
sensory - name, ganglion > 3rd order > end
parasympathetic - name (2) + for (1.2) + ganglion (1.2) + gland (2.1) + receive (2.2) emerge > enter (1) > exit
UMN vs. LMN
- at parotid gland
- UMN: contralateral lower
- LMN: ipsilateral
- main motor nucleus: at RF in pons, receive (B) corticonuclear
- sensory nucleus (solitary tractus): geniculate ganglion -> contralateral VPM of thalamus -> end at taste cortex (43)
parasympathetic
- sup salivary: has submaxillary & sublingual gland, supplies submandibular ganglion, receive hypothalamus & tractus, for taste
- lacrimal: has lacrimal gland, supplies pterygopalatine & sphenopalatine ganglion, receive hypothalamus & trigeminal, for emotional response & lacrimation
- emerge from between pons & medulla -> enter IAM -> exit stylomastoid foramen
CN: Vestibulocochlear Nerve
emerge > enter + with
vestibular - receptor (3), ganglion, afferent (2) efferent (2) + laterality, caloric, doll
cochlear - receptor, ganglion, rinne, weber
emerge between pons & medulla -> enter IAM with CN7
vestibular
- receptor: semicircular canal (motion), utricle & saccule (position)
- scarpa’s ganglion
- afferent: inner ear, cerebellum
- efferent: ipsilateral cerebellum, ipsilateral vestibulospinal tract
- caloric: COWS (slow then FAST)
- doll: deviate contra
cochlear
- receptor: organ of corti
- spiral ganglion
- rinne: BC>AC (abnormal/negative) = weber at abnormal
CN: Glossopharyngeal Nerve
main motor - where, receive (1), muscle (1), name
sensory - ganglia (2), terminate
parasympathetic - name, receive (2), ganglion, gland
main motor nucleus/nucleus ambiguus
- in RF of medulla
- receive: corticonuclear (B)
- muscle: stylopharyngeus
main sensory nuclei
- sup & inf glossopharyngeal ganglion
- terminate at parietal cortex
parasympathetic/inf salivary
- otic ganglion
- has parotid gland
- receive: hypothalamus, tractus solitarius
CN: Vagus & Hypoglossal Nerve
VAGUS NERVE
- main motor & main sensory
- gag (afferent & efferent), uvula
HYPOGLOSSAL NERVE
- muscle, except muscle
VAGUS NERVE
- main motor (ambiguus), main sensory (tractus solitarius)
- gag reflex: CN9 as afferent, CN9&10 as efferent
- uvula deviate contra
HYPOGLOSSAL NERVE
- all tongue intrinsic
- except genioglossus
