Cranial Nerves Flashcards
what is the name of CN I?
olfactory
what is the function of the olfactory nerve?
smell (special visceral afferent)
where does the olfactory nerve exit the skull?
tiny foramina in cribiform plate
what is the name of CN II?
optic
what is the function of the optic nerve?
vision (special somatic afferent)
where does the optic nerve exit the skull?
optic canal
what is the name of CN III?
oculomotor
what is the function of the oculomotor nerve?
innervates the extraocular muscles of the eye and muscles that elevate eye lid
(general somatic efferent)
what are the muscles that are innervated by the oculomotor nerve? (5)
(1) superior rectus
(2) inferior rectus
(3) medial rectus
(4) inferior oblique
(5) levator palpebrae superior
where does the oculomotor nerve exit the skull?
superior orbital fissure
what is the name of CN IV?
trochlear
what is the one muscle of the eye that is innervated by the trochlear nerve?
superior oblique muscle
what is the function of trochlear nerve? (2)
(1) innervates superior oblique muscle of eye
(2) abduction, depression and IR of eye
(general somatic efferent)
if the trochlear nerve is damaged, what can happen as a result? (2)
(1) double vision
(2) head tilt to compensate for externally rotated eye
where does the trochelar nerve exit the skull?
superior orbital fissure
what is the name of CN V?
trigeminal
what is the function of the trigeminal nerve?
gives rise to 3 main branches V1: ophthalmic V2: maxillary V3: mandibular (general somatic afferent)
where does the trigeminal nerve exit the skull? (3)
(1) ophthalmic: superior orbital fissure
(2) maxillary: foramen rotundum
(3) mandibular: foramen ovale
what is the name of CN VI?
abducens
what muscle does the abducens innervate?
lateral rectus muscle
if the abducens nerve is damaged, what can happen as a result? (2)
(1) postviral in younger patients
(2) mononeuropathy in older
where does the abducens nerve leave the skull?
superior orbital fissure
how can you remember what nerves innervate the muscles of the eye?
LR6-SO4-R3
lateral rectus: CN 6
superior oblique: CN 4
rest: CN 3
what is the name of CN VII?
facial
what is the function of the facial nerve? (3)
(1) facial expression
(2) taste of anterior 2/3 of tongue
(3) mandibular and sublingual salivary glands; lacrimal gland (and others of nose and palate)
what can dysfunction of the facial nerve cause?
facial paralysis
where does the facial nerve exit the skull? (3)
(1) internal acoustic meatus
(2) facial canal
(3) stylomastoid foramen
what is the name of CN VIII?
vestibulocochlear
what is the function of the vestibulocochlear nerve? (2)
(1) hearing
(2) position and movement sense
what can dysfunction of the vestibulocochlear nerve cause? (2)
(1) deafness
(2) vertigo
where does the vestibulocochlear nerve exit the skull?
internal acoustic meatus
what is the name of CN IX?
glossopharyngeal
what are the functions of the glossopharyngeal nerve? (4)
(1) swallowing
(2) parotid gland innervation
(3) taste posterior 1/3 of tongue
(4) cutaneous sensation of external ear
where does the glossopharyngeal nerve exit the skull?
jugular foramen
what is the name of CN X?
vagus
what is the function of the vagus nerve? (5)
(1) muscles of pharynx (except stylopharyngeus), intrinsic muscles of larynx, most muscles of palate
(2) smooth muscle of trachea, bronchi, digestive tract
(3) nodes for conductive systrem of heart
(4) sensory for tongue to stomach and intestines
(5) taste
where does the vagus nerve exit the skull?
jugular foramen
what is the name of CN XI?
accessory
what is the function of the spinal accessory nerve? (1)
(1) innervates SCOM and traps
where does the spinal accessory nerve exit the skull?
jugular foramen
what is the name of CN XII?
hypoglossal
what is the function of the hypoglossal nerve?
(1) intrinsic and extrinsic muscles of tongue
what nerve is commonly affected after a stoke?
hypoglossal
where does the hypoglossal nerve exit the skull?
hypoglossal canal
for the first 6 cranial nerves, do they provide sensory, motor or both?
CN I: sensory CN II: sensory CN III: motor CN IV: motor CN V: both CN VI: motor
for the last 6 cranial nerves, do they provide sensory, motor or both?
CN VII: both CN VIII: sensory CN IX: both CN X: both CN XI: motor CN XII: motor
