Cranial Nerves Flashcards
CN I
olfactory
CN II
optic
CN III
oculomotor
CN IV
trochlear
CN V
trigeminal
CN VI
abducens
CN VII
facial
CN VIII
vestibulocochlear
CN IX
glossopharyngeal
CN X
vagus
CN XI
spinal accessory
CN XII
hypoglossal
What two cranial nerves are extensions of the CNS?
olfactory
optic
Cranial nerves in midbrain
III
IV
part of V
Cranial nerves in pons
V, VI, VII, VIII
Cranial nerves in medulla
part of V
IX
X
XII
Parasympathetic ganglion from oculomotor nerve
Ciliary
Parasympathetic ganglion from facial nerve
pterygopalatine and submandibular
Parasympathetic ganglion from glossopharyngeal
otic
Parasympathetic ganglion from vagus nerve
pharynx, larynx
Sympathetic innervation of head and neck run along with …and cranial nerves from the ….ganglion.
arteries
superior cervical ganglion
Two exceptions that do not run with blood vessels
deep petrosal nerves
long ciliary nerves
Olfactory nerve function
sense of smell
Olfactory nerves run through the … of ethmoid bone to the ….
cribriform plate
olfactory bulb
Anosmia
loss of smell
How does anosmia happen?
skull fractures or sudden blows to the head that causes shearing cranial nerves at the cribriform plate causing loss of smell
Optic nerve function
sense of sight
Optic tract continues on to enter the diencephalon and terminates in the …
lateral geniculate body
Orbital tumor causes or lesion on right optic nerve
right sided blindness
Pituitary tumor causes or lesion on optic chiasm
bitemporal hemiansopsia or tunnel vision
Lesions on the right optic tract or an aneurysm
left homonymous hemianopsia or loss of left side field of vision on both eyes
Oculomotor originates from two midbrain nuclei
edinger-westphal nucleus (parasympathetics)
nucleus of oculomotor nerve (motor)
Oculomotor nerve serves 5 skeletal muscles: four eye muscles and one upper eye lid muscle
eye muscles: superior, medial and inferior rectus and inferior oblique muscle
upper eye lid: levator palpebrae, superioris muscle
Oculomotor nerve lies within the… and exits the mesencephalon is within the ….
oculomotor nuclear complex
middle cranial fossa
The oculomotor nerve divides into two branches within the superior orbital fissure
superior and inferior division
The superior division of the oculomotor nerve supplies two muscles
levator palpebrae superioris
superior rectus
The inferior division of the oculomotor nerve supplies three muscles
medial, inferior rectus and inferior oblique
The parasympathetic fibers part of CN III in Edinger-Westphall nucleus controls
sphincter pupillae muscle (constricts pupil) and ciliary (rounds lens for near vision)
Oculomotor nerve lesions lead to
strabismus (eye rotating down and abducted due to unopposed action of lateral rectus and superior oblique muscles)
ptosis
loss of accommodation of lens
Aneurysm within the .. can cause sudden CN III palsy
posterior cerebral
superior cerebellar
posterior communication artery
Trochlear nerve is the only CN which
exits from the dorsal surface of the brain
Trochlear nerve controls
superior oblique
Trochlear nerve runs within the lateral wall of the cavernous sinus through the … to the superior oblique muscle of the eye.
superior orbital fissure
LMN lesion of CN IV causes …
head tilt about 3-4 degrees
Abducens nerve goes to ….of the eye.
lateral rectus muscle
Cell bodies of abducens nerve lie within …
abducens nucleus
Abducens nerve exits the brain stem at the …. and course through ….
junction of the pons and medulla
Dorello’s canal
Lesions of abducens nerve
eye rotates inward because of paralysis of lateral rectus muscle
Trigeminal nerve is the
largest
Trigeminal nerve supplies
sensory from face, scalp, nose, paranasal sinus, eye, mouth and teeth and motor for muscles of mastication
Branches of trigeminal nerve
ophthalmic (V1)
maxillary (V2)
mandibular (V3)
Ophthalmic branch exits from
Maxillary branch exits from
Mandibular branch exits from
superior orbital fissure
foramen rotundum
foramen ovale
Ophthalmic division branches
lacrimal
frontal
nasociliary
long ciliary
Maxillary division branches
zygomatic
infraorbital
superior alveolar
pterygopalatine
Mandibular division branches
buccal
auriculotemporal
lingual
inferior alveolar
Mastication muscles (major)
temporalis and masseter
medial and lateral pteyrgoids
Trigeminal neuralgia or Tic doloureux
severe, sudden pain in the regions covered by trigeminal nerve
Facial nerve functions
moves facial muscles
lacrimal and nasal glands from superior salivatory nucleus
taste from anterior 2/3 of tongue and a little bit of eardrum
The ….nucleus stimulates lacrimal and submandibular and sublingual salivary glands.
superior salvitory nucleus
Facial nerve exits the posterior cavity by the
internal acoustic meatus
The facial nerve has three major nuclei in the pons
motor nucleus (facial muscles) superior salivatory nucleus (glands) Solitary nucleus (taste on anterior 2/3)
Branches of facial nerve
temporal zygomatic buccal mandibular cervical posterior auricular
CN VII has …exits from temporal bone.
3
Vestibulocochlear nerve functions
hearing and balance
Cochlear division nerve cell bodies lie within the …
spiral cochlear ganglion
The vestibulocochlear nerve sends information to two nuclei on the pons
vestibular and cochlear
Nerve cell bodies from the vestibular division lie in the … and receive information from hair cells within the …
vestibular ganglion
saccule
utricle
semicircular canals
Glossopharyngeal nerve functions
elevate pharynx parotid gland secretions senses arterial O2 touch, temp and pain from posterior 1/3 taste from posterior 1/3
Glossopharyngeal nerve exits out the
jugular foramen
All parasympathetic control of salivary glands passes through the…..
middle ear chorda tympani (CN VIII and tympanic nerve CN IX)
Vagus nerve functions
speaking and swallowing
visceral smooth muscle and glandular secretions in pharynx, larynx and GI
sensory from head, neck, lungs, heart and GI
touch, pain and temp from pharynx, larynx and eardrum
and a few tastebuds
Vagus nerve exits
jugular foramen
The branchial motor portion of the vagus nerve controls all muscles of
larynx
pharynx
palate
The vagus nerve has 3 major medullary nuclei
nucleus ambiguus
posterior motor nucleus of vagus
solitary nucleus and spinal nucleus of trigeminal
Lost vagus nerve on one side results in
droop of arch of soft palate and uvula
Hypoglossal nerve function
tongue movements
Hypoglossal nucleus exits as
the medulla as a number of rootlets
Hypoglossal nerve exits
hypoglossal canal
LMN of hypoglossal shows.
tongue deviation to same side as lesion when tongue is protruded
