Cranial Nerves Flashcards
name CN I
Olfactory nerve
CNS origin for CN I
Cerebrum
Nuclei origin for CN I
Nasal mucosa
Skull opening CN I exits/enters
Cribriform foramina of ethmoid bone
Target structures of CN I
Nasal mucus (nasal passageways)
Axon function of CN I
Sensory (special sense= smell)
Name CN II
Olfactory nerve
Nuclei origin of CN II
Ganglion cells of retina
Skull opening CN II enters/exits
Optic Canal
Target structures for CN II
Eyes (retina)
Axon function for CN II
Sensory (vision)
Name CN III
Oculomotor nerve
What are the cells of origin for CN III (Motor and Parasympathetic)
Motor: oculomotor nucleus
Parasympathetic :accessory oculomotor nucleus
What are the skull openings CN III enters/exits
Superior orbital fissure
What are the target structures for CN III motor branches superior ramus
levator palepbrae superioris muscle (upper eyelid)
Superior rectus muscle (elevates eye)
What are the target structures for CN III parasympathetic nerves?
Ciliary bodies (lets eye adjust focal point to far/close) Iris (constriction)
What are the target structures for CN III inferior ramus of Motor?
Medial rectus (look inward) Inferior rectus (look downward) Inferior oblique (look downward)
What are the axon functions for CN III
Motor & parasympathetic
What ganglia is associated with CN III?
Ciliary ganglion
What nerve does CN III’s parasympathetic tract hitchhike on?
Short Ciliary Nerve of V1 (Ophthalmic) of Trigeminal nerve)
What nerve is the Ciliary ganglion suspended from?
Short ciliary nerve of Opthalmic nerve of Trigeminal nerve (V1 of nerve V)
What is the CNS origin of CN IV?
Midbrain
Where are the cells of origin for CN IV?
Trochlear nucleus
What skull openings does CN IV nerve enter/exit?
Superior orbital fissure
What is the target structure of CN IV
superior oblique muscle (eye looks down & out)
What is the axon function of CN IV
Motor
What is the name of V1 nerve?
Opthalmic nerve
What nerve does V1 originate from?
Trigeminal nerve
What is the CNS origin of V1 nerve?
Pons
Where do the cells of origin start for V1 nerve?
Trigeminal ganglion
What skull openings does the main part of V1 enter/exit?
Superior orbital fissure
What skull openings/exits do the branches of V1 enter/exit? (Name by branch)
1) Anterior ethmoid nerve: anterior ethmoidal foramen
2) Posterior ethmoid nerve: posterior ethmoidal foramen
3) Supraorbital nerve: Supraorbital foramen
What are the target structures for the lacrimal branch of V1?
1) lacrimal gland
2) skin on lateral aspect of upper eyelid
What are the target structures for the frontal branch of V1?
1) skin of forehead (Supraorbital)
2) skin of medial forehead (supratrochlear)
What are the target structures for the Nasociliary branch of V1?
1) mucosa of frontal & ethmoid sinuses AND skin on nose (anterior ethmoid)
2) mucosa of sphenoidal & ethmoidal sinuses AND superior nasal cavity (posterior ethmoid)
3) eye (long ciliary)
4) eye + parasympathetic via CN III (short ciliary)
5) skin on the bridge of the nose (infratrochlear)
What are the axon functions of V1
Sensory only
What ganglia and type is associated with V1
Trigeminal sensory nucleus is the ganglion & it’s sensory!
What other parasympathetic nerves and from where is V1 associated with/ allows “hitch hikers” from?
1) Cilary ganglion from CN III (parasympathetic) & short ciliary parasympathetic to ciliary bodies in eyes
2) parasympathetic from CN VII from the communicating branch off of the lacrimal nerve to V2 (which has the VII ganglion) & then carries the parasympathetic nerve to the lacrimal gland.
What is the name for V2 nerve?
Maxillary nerve
What nerve does V2 originate from?
Trigeminal nerve (V)
What is the CNS origin of V2?
Pons
Where are the cells of origin of V2 from?
Trigeminal ganglion
What is the main skull opening V2 enters/exits
Foramen rotundum
What other skull openings do branches of V2 exit/enter
1) inferior orbital fissure (zygomatic)
2) pterygomaxillary fissure (posterior superior alveolar)
3) Sphenopalatine foramen (nasopalatine)
4) greater palatine foramen (greater palatine nerve)
5) lesser palatine foramen (lesser palatine nerve)
6) Palatovaginal canal (pharyngeal n.)
7) infraorbital foramen (infraorbital n.)
What are the target structures of V2?
1) skin of the mid face
2) teeth
3) mucus membranes of the upper palate
4) nasopharynx
What is the axon function of V2?
Sensory!
What ganglia is associated with V2?
Trigeminal sensory nuclei
Additional structures of V2?
1) pterygopalatine fossa: where most of the nerves run through to enter respective foramen
2) Pterygopalatine ganglion is from CN VII (parasympathetic) & suspends in pterygopalatine fossa & follows peripheral nerves —> for example to larcrimal glad via V1 from the communicating branch
What is name of V3 nerve?
Mandibular nerve
What is the nerve origin of V3 nerve?
Trigeminal
What is the CNS origin of V3?
Pons
What are cells of origin for V3?
1) Sensory: Trigeminal ganglia
2) Motor: Trigeminal motor nuclei
What is the main skull opening V3 enters/exits
Foramen ovale
What additional skull openings does V3 enter/exit?
1) Foramen spinosum (meningeal n.)
2) Mandibular foramen (mental n.)
3) mental foramen (mental n.)
What are the target structures of the motor part of V3?
1) muscles of mastication:
a) temporalis (deep temporal n.)
b) masseter (masseteric n.)
c) lateral pterygoid (lat. pterygoid n.)
d) medial pterygoid (medial pterygoid n.)
2) Suprahyoid muscles:
a) mylohyoid
b) anterior digastric
What are the target structures of sensory of V3?
1) skin of lower face
2) anterior 2/3 of tongue
3) mouth
4) mandibular teeth
5) ear
What are the axon functions for V3?
1) motor
2) sensory
What is different about V3 motor nerves?
V3 motor nerves are from the 1st pharyngeal arch (mandibular arch) & originate from embryonic pharyngeal arches for motor as opposed to somites that formed all other muscles/motor nerves.
What ganglia is associated with V3?
Trigeminal sensory nuclei
What additional structures are related to V3?
1) Submandibular ganglion from CN VII —> suspended from & follows lingual nerve to tongue
2) Otic ganglion from CN IX —> suspended from & follows auriculotemporal nerve to the parotid gland
Both are parasympathetic innervation!
What is the name for CN VI?
Abducens nerve
What is the CNS origin of CN VI?
Pons
What is the cells of origin for CN VI?
Abducens nuclei
What is the target structure for CN VI?
Lateral rectus muscle
What skull openings does CN VI enter/exit
Superior orbital fissure
What is the axon function for CN VI?
Motor
Name for CN VII
Facial nerve
What is the CNS origin for CN VII?
Pons
What are the cells of origin for CN VII: list for each type of function…
1) Motor: Facial motor nucleus
2) Sensory: Geniculate ganglion
3) Parasympathetic: superior salivary nucleus
What is the main skull opening CN VII enters/exits?
Internal auditory meatus
What additional openings do branches of CN VII travel through?
1) Hiatus of greater petrosal nerve (Greater Petrosal Nerve —> sensory & parasympathetic)
2) Stylomastoid foramen (Main root —> motor & sensory)
3) Petrotympanic fissure (Chorda Tympani —> sensory & parasympathetic)
What are the target structures for the motor aspect of CN VII?
Muscles of facial expression + stylohyoid + posterior digastric
What’s different about CN VII’s motor aspect?
Motor nerves originate from pharyngeal arch #2 (hyoid arch)!
What are the target structures for the sensory aspect of CN VII?
Two types of sensory:
1) typical sensing & proprioception:
posterior ear, external auditory meatus, tympanic membrane, facial muscle
2) Taste! [anterior 2/3 of tongue & taste of palate!]
What are the target structures for the parasympathetic aspect of CN VII?
1) lacrimal gland (tears)
2) palate/nasopharyngeal mucosa (snot)
3) sublingual gland (spit)
4) submandibular gland (spit)
What are the axon functions for CN VII?
1) Motor
2) Sensory + Special sense (taste)
3) parasympathetic
What ganglia are associated with CN VII?
1) sensory: geniculate ganglion
2) special sense (taste): nucleus solitarius
3) parasympathetic:
a) submandibular ganglion
b) pterygopalatine ganglion
What additional structures are part of CN VII?
1) Main root (motor & sensory to muscles of facial expression & posterior ear)
2) Chorda tympani (sensory & parasympathetic to tongue/sublingual/submandibular)
3) Greater petrosal nerve (sensory & parasympathetic to the pterygopalatine fossa (and ultimately to the palate & lacrimal gland)
Name CN VIII?
Vestibulocochlear
What is CNS origin of CN VIII?
Pons
What are the cells of origin for CN VIII?
1) Vestibular ganglion (vestibular sense)
2) Spiral ganglion (hearing sense)
Main skull openings CN VIII enters/exits
Internal auditory meatus
Target structures for CN VIII:
1) hair cells of ampulla ray crests in semicircular ducts (vestibular sense)
2) hair cells of spiral organ (cochlear/ hearing sense)
Axon functions of CN VIII
Special senses: 1) vestibular 2) hearing
Associated ganglia for CN VIII
Sensory ganglia:
1) Vestibular nuclei
2) dorsal/ventricle cochlear nuclei
What is name of CN IX
Glossopharyngeal
What is CNS origin of CN IX?
Medulla
What are cells of origin for CN IX?
1) motor: nucleus ambiguous
2) sensory : superior ganglion & inferior ganglion
3) parasympathetic : inferior salivatory nucleus
Main skull opening CN IX enters/exits
Jugular foramen
Other skull openings CN IX enters/exits
Tympanic cannaliculus (parasympathetic & sensory enter/exit in ear region) Foramen ovale (parasympathetic enters/exits to get to V3 for otic ganglion)
What are the target structures for CN IX?
1) motor: stylopharyngeus muscle
2) parasympathetic: parotid gland via otic ganglion
3) sensory:
a) proprioception/touch: tonsils, tympanic of inner ear, gag reflex of upper pharynx
b) special sense: taste: posterior 1/3 tongue
c) special sense: visceral: carotid body (chemoreception) & carotid sinus (baroreception)
What is different about motor aspect of CN IX?
Motor nerve of CN IX is from the 3rd pharyngeal arch (stylopharyngeal arch!) & innervates stylopharyngeusl muscle!
What are the axon functions for CN IX?
1) motor
2) parasympathetic
3) sensory
What ganglia are associated with CN IX?
1) otic ganglion (parasympathetic)
2) Trigeminal sensory nucleus (regular sensory)
3) Nucleus solitarius (special senses)
Additional structures for CN IX?
1) tympanic nerve (sensory + parasympathetic)
2) lesser petrosal nerve (parasympathetic)
Name of CN XII?
Hypoglossal nerve
CNS origin of CN XII?
Medulla
Cells of origin for CN XII?
Hypoglossal nucleus
Skull openings CN XII enters/exits
Hypoglossal canal
Target structures for CN XII?
Genioglossus, styloglossus, Hyoglossus, intrinsic muscles of tongue
Axon function of CN XII?
Motor
Name CN XI
Accessory nerve
What is CNS origin of CN XI?
Spinal cord
What are spinal nerves for CN XI?
C1-C5
What openings in skull does CN XI enter/exit?
1) foramen magnum
2) jugular foramen
What are the target structures for CN XI?
1) Sternocleidomastoid muscle
2) trapezius muscle
What is the axon function for CN XI?
Motor
Name CN X?
Vagus nerve
What is CNS origin of CN X?
Medulla
What are cells of origin for CN X?
1) motor: nucleus ambiguous
2) parasympathetic: dorsal motor nucleus
3) sensory: superior & inferior ganglion
What skull openings does CN X enter/exit
Jugular foramen
What are target structures for motor of CN X?
Muscles of pharynx, intrinsic laryngeal muscles, palate, upper 2/3 of esophagus, cricothyroid, inferior pharyngeal constrictor, levator veli palatini
What are the parasympathetic target structures for CN X?
Mucosa of palate, mucosa of pharynx, mucosa of vocal cords & trachea, viscera of thorax & abdomen
What are the sensory target structures of CN X?
1) touch/proprioception: skin of ears, external auditory meatus, dura of posterior cranial fossa
2) taste: epiglottis and palate
3) Viscera: baroreception of aortic arch, viscera of thorax/abdomen
What is different about motor aspect of CN X?
Motor aspect come from both 4th & 6th pharyngeal arches [4th: superior laryngeal [cricothyroid m.] [6th: recurrent laryngeal [intrinsic laryngeal m.]
What ganglia are associated with CN X?
1) superior ganglia [sensory]
2) inferior ganglia [sensory]
3) ganglia in/on/near viscera [parasympathetic]
4) spinal Trigeminal nucleus [sensory]
