15 JULY Flashcards
brainstem:
1-2
midbrain
3-4
pons
5-8
medulla
9-12
overall four fx of the cranial nerves
motor innervation
somatosensory
special senses
parasympathetic control
corticobrainstem trarct
crosses midline
corticobrainstem tract always present
ipslaterally
so CN always present
ipslaterally
CN are also called
corticobulbr
corticobrainstem tract are defined as two things
peripheral sensory
LMN
CN I:
olfactory nerve
olfacotry has what tract
insular cortex amygdala paranippocranial gyrus
dsyfx of CN I
olfactory
- losses sense of smell
overall how can CNs get damaged
- MVA : get sheered
- concussion if big enough
- surgery
pt with CN I dsfx complain of
their food not tasting the same
CN II:
optic nerve
the optic nerve def:
bundle of axons in the retina: retina ganlgia cells
optic nerve tract goes from
retina to the X
dsyfx of CN II ;
optic : visual acuity - sight
why is the CN V: trigeminal so BIG?
because it has a high density of fine disciminative sensation
list the cranial nerves of extraocular Mm
III: oculomotor
IV: trochlear
VI: abducens
CN III?
oculomotor
CN IV?
trochlear
CN VI?
ABducens
CN V?
trigeminal
trochelar does what?
IV - turns eyes toward the tip of the nose : down and in
ABducens does what?
VI - turns eyes straight to the side: ABduct in straight plane
oculomotor does what?
III - turns eyes everywhere else that wasn’t mentioned in IV or VI
Trigeminal affects what sensory modalities
- discriminative touch
- proprioception
- disc. pain
- divergent pain
CN V heads in what direction
in (trigeminal)
CN VII: heads in what direction
out (facial)
the difference in function for clearing out the eyes in CN V / VII
CN V: sense an irritant
CN VII: gets rid of the irritant
CN V: trigeminal feeds what area of the body
just kenny’s face
so the anterior portion of your face
if you poke a pt’s eye and there is no response but they can blink with voluntary control this means that
CN V: trigeminal is broken
if a pt doesn’t have voluntary control of closing eye lid then that means
CN VII: facial is broken
how do you test CN VII:
make faces = facial expressions
CN V also does what motor function?
massetication :
- chewing and talking
CN VII?
facial nerve
the facial nerve VII innervates what?
tongue pharynx little piece of the ear glands: - salivary - nasal - lacrimal
a peripheral motor neuron dx presents:
iplsateral paralysis
bells palsy def:
paralysis of facial expression some from fo dx of facial n VII
difference between a stroke and bells palsey ?
bells palsey : paralysis of whole face (1/2) upper and lower
stroke: paralysis of half face (1/4) lower
CN VIII?
vestibulocochlear
the vestibulocochlear has two parts?
- equilibrium ; vestibulo part
2. hearing ; cochlear part
the vestibulocochlear does three things?
- transduction of sound
- turns “air waves” into “water waves”
- each part of the cochlea is “tuned” to a particular frequency
so the WIDE portion of the cochlea is
slow waves
low frequence
so the NARROW portion of the cochlea is
fast waves
high frequency
the forehead has what innervation
bilateral UMN
dysfx of hearing can be because of three things:
conducture: outer middle
ear wax: muffled sounds from bones of middle ear can’t flex
converting air to water
auditory info comes from two things:
orientating to sound and visual
the inferior colliculus does what?
orients head and eyes to sound
the reticular formation
adjusts arousal to sound
what orients the head to the sound
inferior colliculus
what adjusts the arousal to sound
reticular formation
conscious awareness and recognition o sound comes from
pharynx auditory cortex
and medial geniculate body
how does distance and sound work?
so the head gets bilateral projections to form 360*
it measures out the distance by when the sound hit what ear first
sound ends in the
temporal lobe
sensorineural loss is due to two things:
dead hair cells
cochlear N APs can’t get through
tinnitus
rining in the ear
why does tinnitus occur
the inner ear is sending APs when there is no stimulus
- indicates something is irritated
the swallow reflex vs. gag reflex
swallow = lets thing in gag = kicks them out
cartoid sinus helps us
determine blood pressure
CN IX:
glossopharnygeal
the glossopharyngeal handles five things?
- somatosensation
- taste in 1/3 tongue
- carotid sinus
- pharyngeal muscle
- parotid salivary gland
importance of taste in the CN IX : glossopharyngeal
lets the brain know that there is something there:
hello! swallow me!
starts the swallow or gag reflex
the swallow/ gag reflex would be damaged by what cranial nerve?
CN IX: glossopharyngeal
what somatosensation does cranial nerve IX work on?
glossopharyngeal :
- soft palate
- phayrnx
- afferent swallow gag reflex
dsfx in CN IX would cause:
glossopharyngeal
1. diminished swallow/gag
decreased salvation
CN X?
VAGUS
the vagus nerve innervates what two things?
pharynx
larynx
the vagus nerve gives afferent signals to what two things?
the abdominal visceral organs
together there are four things the vagus nerve works on?
- efferent
- pharynx
- larynx - afferent
- abdominal
- heart (visceral org)
list the four dsfx of the CN X: vagus
- difficulty speakng: hoarse voice
- difficulty swallowing
- asymmetric elevation of soft palate
- poor digestion
the difference in dx to one side / both side of UVULA:
both side : whole thing won’t elevate
one side: asymmetrical elevation
what is the UVULA:
punching bag in the back of the throat
when you go “ahhhh” at the doctors you are testing what nerve?
CN X: Vagus
constipation by indicate what nerve damage?
CN X: Vagus
CN XI?
spinal accessory
spinal accessory innervates what two things?
striated mus attached to head:
- sternocleidomastoid
- trapezius
difference between testing sternocleidomastoid and trapezius?
sternocl. = test lying down trap = can tell standing up
dsyfx of CN XI:
spinal accessory:
the weak muscle that it innervated: striated muscle attached to the head
CN XII???
hypoglossal
dsfx from CN XII?
hypoglossal
speaking
swallowing
if you dx the hypoglossal the tongue will do what
and it indicates what?
the tongue sticks out and the side that it sticks out towards the weak side
list the three stages of swallowing and the CNs that go into that one
oral: V, VII, XII
pharygneal: IX, X
esophageal: X
what does CN V do for swallowing?
trigmeninal: moves food up and down
what does CN VII do for swallowing?
facial: keeps mouth close to keep food inside
what does CN XII do for swallowing?
moves food side to side so food can get mash
what does CN IX do for swallowing?
ask the brain if its ok to swallow
what does CN X do for swallowing?
starts swallow takes care of peristalsis in the mouth for bolus
dsyphagia is
the difficulty swallowing
dysarthria
inability to speak
larynx is innervated by
CN X: vagus
soft palate is innerved by:
CN X: vagus
jaw is innervated by:
CN V; trigeminal
lips are innervated by:
CN VII: facial
tongue is innervated by
CN XII: hypoglossal
