Introduction to the Cranial Nerves Flashcards
___ sets of cranial nerves exit foramina of the skull
like the spinal nerves, they are part of the ___ system
by convention, they’re designated by roman numerals ___a
12
peripheral nervous
I - XII
cranial nerve I (___) is associated w/ the ___
cranial nerve II (___) develops from the ___
all the rest are associated w/ the ___
olfactory
telencephalon
optic
diencephalon
brainstem
midbrain cranial nerves (2)
CN III (oculomotor) CN IV (trochlear)
pons cranial nerves (4)
CN V (trigeminal) CN VI (abducens) CN VII (facial) CN VIII (vestibulocochlear)
medulla oblongata cranial nerves (4)
CN IX (glossopharyngeal) CN X (vagus) CN XI (accessory) CN XII (hypoglossal)
cranial nerves III, VII, IX, & X contain (preganglionic/postganglionic) (sympathetic/parasympathetic) fibers
preganglionic
parasympathetic
the cell bodies of all general sensory neurons (___ neurons) are located in the ganglia of the following cranial nerves (4)
pseudounipolar
(V) trigeminal nerve
(VII) facial nerve
(IX) glossopharyngeal nerve
(X) vagus nerve
the cell bodies of taste neurons (___ neurons) are located in the ganglia of the following cranial nerves (3)
pdeudounipolar
(VII) facial nerve
(IX) glossopharyngeal nerve
(X) vagus nerve
the cell bodies of motor neurons (___ neurons) are located in separate & discrete units called ___ within the ___
multipolar
nuclei
brainstem
the ___ nerves innervate all of the structures derived from the branchial arches
branchiomeric cranial
the branchiomeric cranial nerves innervate all of the structures derived from the ___
branchial arches
branchiomeric cranial nerves & corresponding branchial arches (5)
trigeminal nerve (V) - branchial arch 1 facial nerve (VII) - branchial arch 2 glossopharyngeal nerve (IX) - branchial arch 3 vagus nerve (X) - branchial arches 4-6 accessory nerve (XI) - branchila arches beyond 6?
the skeletal muscles derived from somites are innervated by ___ nerves & some of the ___ nerves & are said to be innervated by (somatic/visceral) (sensory/motor) fibers (___)
the skeletal muscles derived from branchial arches & innervated by the a branchiomeric cranial nerves are said to be innervated by ___ (sensory/motor) fibers (___)
spinal
cranial
somatic motor fibers (general somatic efferent)
branchial motor fibers (special visceral efferent)
oculomotor nerve (III):
cranial nerve
ganglion
target structures (2)
parasympathetic (motor) root of the ciliary ganglion (preganglionic fibers)
ciliary ganglion (postganglionic fibers)
ciliary muscle
sphincter of the pupil
facial nerve (VII) (nervus intermedius portion):
cranial nerve (g)
ganglion
target structures (3)
greater petrosal nerve (preganglionic fibers)
pterygopalatine ganglion (postganglionic fibers)
lacrimal gland
nasal glands
palatine glands
facial nerve (VII) (nervus intermedius portion):
cranial nerve (c)
ganglion
target structures (3)
chorda tympani nerve (preganglionic fibers)
submandibular ganglion (postganglionic fibers)
submandibular gland
sublingual gland
lingual glands
glossopharyngeal nerve (IX):
cranial nerve
ganglion
target structure (1)
lesser petrosal nerve (preganglionic fibers)
otic ganglion (postganglionic fibers)
parotid gland
olfactory nerve (CN I):
primitive (sensory/motor) nerve containing specialized (unipolar/bipolar) neurons in the ___ mucosa
bundles of axons from these neurons constitute olfactory nerves which proceed through the ___ plate of the ___ bone & end in the ___ of the (forebrain/midbrain/hindbrain)
contains special (sensory/motor) fibers for ___
sensory
bipolar
olfactory
cribriform plate of the ethmoid bone
olfactory bulb
forebrain
sensory
smell
optic nerve (CN II):
travels through the ___ along w/ the ___ artery
contains special (sensory/motor) fibers for ___
optic canal
ophthalmic
sensory
sight
oculomotor nerve (CN III):
contains (somatic/visceral) (sensory/motor) & (sympathetic/parasympathetic) fibers
emerges from the ventral aspect of the (forebrain/midbrain/hindbrain) & proceeds through the lateral wall of the ___ sinus & enters the orbit through the ___ fissure where it immediately divides into two divisions (2)
somatic motor
parasympathetic
midbrain
cavernous
superior orbital
superior
inferior
oculomotor nerve (CN III):
muscles that the superior division supplies (2)
levator palpebrae superioris
superior rectus eye
oculomotor nerve (CN III):
muscles that the inferior division supplies (3)
medial rectus eye
inferior rectus eye
inferior oblique eye
oculomotor nerve (CN III):
the only ocular muscles not supplied by the oculomotor nerve (2)
superior oblique (CN IV) lateral rectus (CN VI)
oculomotor nerve (CN III):
the preganglionic parasympathetic fibers of the oculomotor nerve travel w/ the ___ division & depart from it as the (sympathetic/parasympathetic) (sensory/motor) root of the ___ ganglion
these fibers synapse w/ (preganglionic/postganglionic) (sympathetic/parasympathetic) neurons in the ___ ganglion
inferior
parasympathetic
motor
ciliary
postganglionic
parasympathetic
ciliary
oculomotor nerve (CN III):
postganglionic parasympathetic fibers depart from the ciliary ganglion within the ___ nerves & proceed to the eyeball where they supply:
- ___ muscle (involved in accommodation of the lens for near vision)
- ___ (which controls the amount of light entering the eye)
short ciliary
- ciliary
- sphincter of the pupil
oculomotor nerve (CN III):
the antagonist of the sphincter of the pupil is the ___ which is supplied by (preganglionic/postganglionic) (sympathetic/parasympathetic) fibers arising from the ___ ganglion
dilator of the pupil
postganglionic
sympathetic
superior cervical
trochlear nerve (CN IV):
emerges from the (dorsal/ventral) aspect of the (forebrain/midbrain/hindbrain)
supplies the ___ muscle w/ (somatic/visceral) (sensory/motor) fibers
it passes through the lateral wall of the ___ sinus & enters the orbit through the ___ fissure
dorsal
midbrain
superior oblique eye muscle
somatic motor fibers
cavernous
superior orbital
abducens nerve (CN VI):
supplies the ___ muscle w/ (somatic/visceral) (sensory/motor) fibers
it passes through the ___ sinus in the company of the ___ artery & enters the orbit through the ___ fissure
lateral rectus eye muscle
somatic motor fibers
cavernous sinus
internal carotid artery
superior orbital fissure
nerve “formula”
SO4 LR6 AR3
superior oblique - CN 4
laterla rectus - CN 6
all the rest - CN 3
vestibulocochlear nerve (CN VIII):
divisions (2)
enters the ___ meatus in the company of the ___ nerve
first division conveys (sensory/motor) information related to ___ & ___
second division conveys (sensory/motor) information related to ___
vestibular
cochlear
internal acoustic meatus
facial nerve
sensory
balance & equilibrium
sensory
hearing
glossopharyngeal nerve (CN IX):
mixed ___ & ___ nerve
carries (pre/post-ganglionic) (symp/parasymp) fibers
nerve to the ___ branchial arch
sensory & motor
preganglionic parasympathetic fibers
third
glossopharyngeal nerve (CN IX):
emerges from the ___ from a groove called the ___ sulcus
its sensory fibers originate from pseudounipolar neurons in its two sensory ganglia (___ & ___), which are located in the ___ foramen
it exits the skull through the ___ foramen along w/ the ___ nerve (CN ___) & the ___ nerve (CN ___)
medulla oblongata
post olivary sulcus
superior & inferior
jugular foramen
jugular foramen vagus nerve (CN X) accessory nerve (CN XI)
glossopharyngeal nerve (CN IX): major branches:
\_\_\_ branch \_\_\_ nerve (sensory/motor) branch to the \_\_\_ muscle \_\_\_ & \_\_\_ branches \_\_\_ branch
tympanic branch carotid nerve motor branch to the stylopharyngeus muscle pharyngeal & tonsillar branches lingual branch
glossopharyngeal nerve (CN IX): tympanic branch:
enters the ___ cavity
contains all of the (pre/post-ganglionic) (symp/parasymp) fibers of the glossopharyneal nerve & (sensory/motor) fibers for the ___ cavity
tympanic cavity
preganglionic parasympahtetic fibers
sensory fibers for the tympanic cavity
glossopharyngeal nerve (CN IX): tympanic branch:
the tympanic nerve plus (pre/post-ganglionic) (symp/parasymp) fibers from the superior cervical ganglion & a twig from the facial nerve form the ___ plexus within the tympanic cavity
the preganglionic parasympathetic fibers within this plexus then converge as the ___ nerve which passes out of the ___ portion of the ___ bone in the hiatus of the ___ nerve side by side w/ the ___ nerve of CN ___
postganglionic sympathetic fibers
tympanic plexus
lesser petrosal nerve petrous portion temporal bone hiatus of the lesser petrosal nerve greater petrosal nerve of CN VIII
glossopharyngeal nerve (CN IX): tympanic branch:
the lesser petrosal nerve then passes out of the skull through the ___ & enters the ___ fossa
it synapses in the ___ ganglion w/ (pre/post-ganglionic) (symp/parasymp) neurons
these fibers then join the ___ nerve (___) which distributes them to the ___ gland
foramen ovale
infratemporal fossa
otic ganglion
postganglionic parasympathetic neurons
auriculotemporal nerve (V3) parotid gland
glossopharyngeal nerve (CN IX): carotid nerve:
carries (sensory/motor) fibers from ___ (pressure) in the ___ sinus & ___ in the ___ body
sensory fibers
baroreceptors
carotid sinus
chemoreceptors
carotid body
glossopharyngeal nerve (CN IX): motor branch to the stylopharyngeus muscle:
only muscle innervated by the ___ nerve
glossopharyngeal
glossopharyngeal nerve (CN IX): pharyngeal & tonsillar branches:
responsible for general sensation from the mucous membrane of much of the ___ & the ___
pharynx
palatine tonsils
glossopharyngeal nerve (CN IX): lingual branch:
general sensation for the posterior one-third of the ___
___ fibers for the posterior one-third of the ___
tongue
taste fibers
tongue
lesions of the glossopharyngeal nerve:
lesions of the glossopharyngeal nerve don’t induce obvious symptoms assuming the ___ nerve is intact for contraction of the ___ muscles
however, intactness can be tested through the (afferent/efferent) limb of the ___ reflex (e.g., stroking the posterior one-third of the tongue w/ a spatula)
the (afferent/efferent) limb of this reflex is the ___ nerve (CN ___)
the glossopharyngeal nerve can be assessed by testing ___ on the posterior one-third of the ___
the pain referred to the middle ear experienced by a person w/ ___ is due to the fact that CN IX supplies the ___ region as well as the mucous membrane of the middle ear
vagus nerve
pharyngeal muscles
afferent limb
gag reflex
efferent limb vagus nerve (CN X)
taste
tongue
tosnillitis
tonsillar region
vagus nerve (CN X):
nerve of the ___, ___, & ___ branchial arches
mixed ___ & ___ nerve & contains (pre/post-ganglionic) (symp/parasymp) fibers
emerges from the ___ form the ___ sulcus
fourth, fifth, & sixth
mixed sensory & motor
preganglionic parasympathetic
medulla oblongata
post-olivary sulcus
vagus nerve (CN X):
leaves the skull through the ___ foramen w/ the ___ & ___ nerves
the (sensory/motor) fibers of the vagus nerve originate from pseudounipolar neurons of the ___ & ___ ganglia, which are located in the ___ foramen
jugulra foramen
glossopharyneal & accessory nerves
sensory
superior & inferior ganglia
jugular foramen
vagus nerve (CN X): major branches (8)
meningeal branch auricular branch pharyngeal branch carotid branch aortic branch recurrent laryngeal nerves vagal branches below the recurrent laryngeal nerves
vagus nerve (CN X):
major branches:
meningeal branch:
(sensory/motor) to the ___ mater in the posterior ___ fossa
actually consists of (sensory/motor) branches from the ___ nerves, which “hitchhike” on the vagus
sensory
dura mater
posterior cranial fossa
sensory
upper cervical nerves
vagus nerve (CN X):
major branches:
auricular branch:
supplies the ___ meatus & the external surface of the ___ membrane
important b/c irritation may initiate a ___ reflex or ___
external auditory meatus
tympanic membrane
cough reflex
nausea
vagus nerve (CN X):
major branches:
pharyngeal branch:
main (sensory/motor) nerve to the ___
contains (sensory/motor) fibers
this branch, along w/ the pharyngeal branch of cranial nerve IX & postganglionic sympathetic fibers from the superior cervical ganglion, constitute the ___ plexus
sensory
pharynx
sensory & motor
pharyngeal plexus
vagus nerve (CN X):
major branches:
pharyngeal branch:
supplies (sensory/motor) fibers to all of the muscles of the ___ except the ___ & all of the muscles of the ___ except the ___
the (sensory/motor) fibers supply part of the mucosa of the ___
pharynx
stylopharngeus (CN IX)
palate
tensor of the palate (V3)
pharynx
vagus nerve (CN X):
major branches:
carotid branch:
caries (sensory/motor) fibers from ___ (pressure) in the ___ sinus & ___ in the ___ body
sensory
baroreceptors
carotid sinus
chemoreceptors
carotid body
vagus nerve (CN X):
major branches:
aortic branch:
carries (sensory/motor) fibers from ___ (pressure) in the ___ & ___ in the ___ body (adjacent to the aortic arch)
sensory
aortic baroreceptors
aortic arch
chemoreceptors
aortic body
vagus nerve (CN X):
major branches:
superior laryngeal branch:
divides into two branches:
- sensory: ___
- motor: ___
- internal laryngela branch
- external laryngeal branch
vagus nerve (CN X):
major branches:
superior laryngeal branch:
internal laryngeal nerve:
pierces the ___ membrane & supplies the lining of the ___ as far as the vocal cords
also sends branches to the ___ & the valleculae of the ___
note: the fibers proceeding to the valleculae & to the laryngeal of the epiglottis contain ___ fibers
thyrohyoid membrane
larynx
epiglottis
tongue
taste
vagus nerve (CN X):
major branches:
superior laryngeal branch:
external laryngeal nerve:
supplies the ___ muscle & the ___ portion of the ___
the remaining intrinsic muscles of the larynx are supplied by the ___ nerve
cricothyroid muscle
cricopharyngeus portion
inferior constrictor
recurrent laryngeal nerve
vagus nerve (CN X):
major branches:
recurrent laryngeal nerves:
the vagus nerves proceed in the neck within the ___ behind & between the ___ artery & the ___ vein
on the left, the vagus nerve passes in front of the ___
the left recurrent laryngeal nerve arches below & behind the ___ to the left of the ___ & ascends in the groove b/n the ___& the ___
carotid sheath
internal carotid artery
internal jugular vein
arch of the aorta
aorta
ligamentum arteriosum
trachea
esophagus
vagus nerve (CN X):
major branches:
recurrent laryngeal nerves:
the right recurrent laryngeal nerve originates just below the beginning of the ___ artery arching below & behind it to ascend to the ___ in the groove b/n the ___& ___
the recurrent laryngeal nerves supply motor fibers to all of the muscles of the ___ except the ___ muscle & sensory fibers to the ___ & ___ below the level of the vocal cords
subclavian artery
larynx
trachea & esophagus
larynx
cricothyroid muscle
trachea & larynx
vagus nerve (CN X):
major branches:
vagal branches below the recurrent laryngeal nerves:
all vagal branches below the recurrent laryngeal nerves carry (pre/post-ganglionic) (symp/parasymp) fibers & (somatic/visceral) (sensory/motor) fibers for the ___ viscera & ___ organs including the foregut & midgut derivatives
preganglionic parasympathetic fibers
visceral sensory fibers
thoracic viscera
abdominal organs
lesions of the vagus nerve:
symptoms of a lesion in the vagus nerve may include:
- increased ___
- constant ___
- decreased rate of ___
- a sensations of ___
- a ___, ___ voice
- difficulty ___
- increased pulse rate
- constant nausea
- decreased rate of respiratoin
- sensation of suffocation
- hoarse, low voice
- swallowing
lesions of the vagus nerve:
tests used to confirm a lesion of the vagus nerve include:
- the (afferent/efferent) (sensory/motor) limb of the ___ reflex (contraction of the pharyngeal constrictors upon touching the pharyngeal wall or the base of the tongue)
- faulty movement of the ___
- a paralyzed ___ on the affected side as seen w/ a laryngoscope
- efferent motor, gag
- uvula
- vocal cord
accessory nerve (CN XI):
considered to be the nerve of the ___ branchial arches beyond the ___
emerges from the side of the ___ cervical segments of the spinal cord b/n the ___ & ___ rootlets of the respective spinal nerves
hypothetical
sixth
upper five
dorsal & ventral
accessory nerve (CN XI):
ascends through the ___ & exits the skull through the ___ foramen along w/ the ___ & ___ nerves
innervates the ___ muscle & the ___ muscle
foramen magnum
jugular foramen
glossopharyngeal & vagus nerves
sternocleidomastoid muscle
trapezius muscle
lesion of the spinal accessory nerve:
lesion of this nerve will result in weakness in turning the ___ to the opposite side as well as sagging of the ___
head
shoulder
hypoglossal nerve (CN XII):
a pure (sensory/motor) nerve
emerges from the ___ form the ___ sulcus in line w/ the ___ roots of the spinal nerves
motor
medulla oblongata
pre-olivary sulcus
ventral roots
hypoglossal nerve (CN XII):
leaves the cranial cavity through the ___ canal
supplies all of the ___ & ___ muscles of the ___ w/ the exception of the ___, which is supplied by the vagus nerve
hypoglossal
intrinsic & extrinsic muscles of the tongue
palatoglossus
lesion of the hypoglossal nerve:
results in ___ & ___ of the ___ muscles of the tongue
the tongue, when protruded, turns to the (same/opposite) side of the lesion due to the unapposed action of the ___ muscle from the (affected/unaffected) side
all sensations for touch, pressure, temperature, & taste are (affected/unaffected)
paralysis & atrophy
instrinsic muscles
same
genioglossus muscle
unaffected side
unaffected
movements of the eyeball:
the center of the cornea or the center of the pupil is used as the anatomic (anterior/posterior) pole of the eye
all movements of the eye are then related to the direction of the movement of the pole as it rotates on any one of the three axes (3)
anterior pole
horizontal
vertical
sagittal
eyeball movement terminology:
movement of the eye upward: ___
movement of the eye downward: ___
movement of the eye laterally: ___
movement of the eye medially: ___
medial rotation of the upper rim of the cornea (12 o’clock position): ___
lateral rotation of the upper rim of the cornea (12 o’clock position): ___
elevation
depression
abduction
adduction
intorsion
extorsion
basic muscle actions of the eyeball:
b/c the ___ & ___ recti are inserted on the medial side of the vertical axis of the eyeball, they not only ___ & ___ the cornea respectively, but also ___ it medially
for the (superior/inferior) rectus muscle to raise the cornea directly upward, the (superior/inferior) oblique muscle must assist
for the (superior/inferior) rectus muscle to depress the cornea directly downward, the (superior/inferior) oblique muscle must assist
superior & inferior
raise & depress
rotate
superior
inferior
inferior
superior
