lecture 18: CN IX, X Flashcards
pt comes in with unilateral hypoacusis. During rinne, the patient hears tuning fork next to their ear 2x as long as they did over the mastoid
during weber, pt hears the tuning fork louder on the left side
what is diagnosis
neural hearing loss on right ear
true or false, glossopharangela is a motor only n
false, it is mixed
where does the glossophrangeal nerve emerge from the medulla
dorsal to the olives (inferior olivary nuclei)
=rostral to CN X rootlets
the glossophrangeal n emerges ventral or dorsal to the olive
dorsal
which is more rostral, glosso or vagus
glosso
true or false, the glossipharangeal has every type of nuclei except branchial mtoor
false, except somatic motor
what are the 5 types of nuclei involved in glosso n (general names)
visceral sensory
visceral motor
branchial motor
somatic sensory
special sensory
majority of primary sensory neuron cell bodies of glosso n are located where
inferior glossopharyngeal ganglion
where does the glossopharyngeal n exit the skull
via jugular foramen
what nerves exit the skull via the jugular foramen
IX, X, XI
is the visceral motor component of the glossopharyngeal n para or sympathetic
para
where do preganglionic neurons of visceral motor component of the gloospharaneal n originate in the
preganglionic neurons originate in the inferior salivatory nucleus
where does the visceral motor component of the glosso n travel after originating in the inferior salivatory nucleus
travels thru tympanic cavity, exits lesser petrosal foramen and enters foramen ovale
foramen ovale holds the glossopharyngeal n (visceral motor components) and what other nerve
V3
preganglionic parasymp neurons of visceral motor component of glosso synapse where with postganglionic neurons
in otic gangliont
the visceral motor component of the glossopharyngeal n innervates what
parotid gland (causes salivation )
true or false, the parotid gland and visceral motor component of glosso n are influenced by central control
true, influenced by hypothalamus and olfactory system
know the passage of the glossopharangela n visceral motor component
.
true or false, the cell bodies of the preganglioninc parasympathetic neurons of the visceral motor component of the glosso n have their cells bodies in the inferior glossopharyngeal nucleus
false, in the inferior salivatory nucleus
true or false, the cell bodies of the preganglioninc neurons of the visceral sensory component of the glosso n have their cells bodies in the inferior glossopharyngeal nucleus
true
where are the cell bodies of the preganglioninc neurons of the visceral sensory component of the glosso n located
have their cells bodies in the inferior glossopharyngeal nucleus
visceral sensory information is collected by what two structures by the glossopharyngeal n
carotid body
carotid sinus
where are the sensory receptors of primary neurons of the visceral sensory component of the glosso n located
carotid body and carotid sinus
in the visceral sensory component of the glosso n, the primary sensory nuerons synapse where
in caudal part (visceral sensory part) or the nucleus solitaires
true or false, in the visceral sensory component of the glosso n, the primary sensory nuerons synapse in rostral part (visceral sensory part) of the nucleus solitaires
false, caudal part
after synapsing in caudal (visceral sensory) part of the nucleus solitaires, secondary neurons of glossopharangeal n project where
to hypothalamus and reticular fomration
what is the function of having sensory receptors at carotid body in visceral sensory component of the glosso n
chemoreceptor organ at the bifurcation of the common carotid artery which allows us to detect 02, co2, ph in blood
what is the carotid body
chemoreceptor organ at the bifurcation of the common carotid artery which allows us to detect 02, co2, ph in blood
what is the function of having sensory receptors at carotid sinus in visceral sensory component of the glosso n
stretch receptors detect an increase in BP
what is the carotid sinus
dilation of internal carotid artery
what are the 5 names of the glossophrangeal nucleus and their type
nucleus ambiguous (branchial motor)
inferior salivatory nucleus (visceral motor)
nucleus solitarius (caudal) (visceral sensory)
sensory trigeminal nucleus (somatic sensory)
nucleus solitarius (rostral) (special sensory)
the nucleus ambiguous of glosso nucleis is what type
branchial motor
the inferior salivatory nucleus of glosso nucleis is what type
visceral motor
the nucleus solitarius (caudal) of glosso nucleis is what type
visceral sensory
the nucleus solitarius (rostral) of glosso nucleis is what type
special sensory
the sensory trigeminal nucleus of glosso nucleis is what type
somatic sensory
the glossopharyngeal nuclei are located in what general region of the brainstem
rostral medulla
nucleus ambiggues has what function
goes to the sylophrangeus muscle to elevate and dilate pharynx for swallowing)
what type of somatic information is being carried by glossopharyngeal n to the sensory trigeminal nucleis
feeling from posterior 1/3 of tongue and ear),internal surface of tympanic membrane, pharynx and tonsils
what type of special sensory information is being carried by glossopharyngeal n nucleus solitarious
taste sensation for posterior 1/3 of tongue
what is the function of the Branchial motor nucleus of gloosphrangelan n
to stylopharyngess muscle
what is the function of the visceral motor nucleus of gloosphrangelan n
goes to parotid gland
what is the function of the visceral sensory nucleus of gloosphrangelan n
from carotid body and carotid sinus
what is the function of the somatic sensation of gloosphrangelan n
from posterior 1/3 of tongue, skin of external ear and internal surface of tympanic membrane, tonsils and pharynx
what is the function of the special sensation of gloosphrangelan n
taste from posterior 1/3 of tongue
where does the vagus n emerge from the medulla
dorsal to the olives (caudal to the CN IX rootlets)
primary sensory neuron c ell bodies for vagus n are located where
either in superior or inferior vagal ganglion
primary sensory neuron cell bodies for somatic sensation for vagus n are located where
superior vagal ganglion
primary sensory neuron cell bodies for visceral and special sensation for vagus n are located where
inferior vagal ganglion
preganglionic parasympathetic neurons of vagus n synapse in various ganglia where
in neck, thorax, abdomen,
near target tissues
where does the vagus n exit the skul
via jugular foramen
what are the 3 major functions of the vagus n
1) motor control of swallowing
2) motor control of phonation
3) parasympathetic functions
explain motor control of swallowing done by vagus n
vagus n innervates muscles of soft palate and pharynx (except stylophrayngeus (CN IX) and tensor vela palatine (V3)
explain motor control of phonation (speech) done by vagus n
innervates intrinsic laryngeal m
the intrinsic laryngeal muscles are responsible for what
phonation/speech
explain the parasympathetic functions of the vagus n
innervates thoracic and abdominal organs (ex: bronchoconstriction, increase peristalsis, gastric secretions, decrease HR)
in what general division of the brainstem are the vagus nuclei located
rostral medulla
what is the branchial motor nucleus of the vagus nucleus
nucleus ambiggues
what is the visceral motor nucleus of the vagus nucleus
dorsal motor nucleus
what is the visceral sensory nucleus of the vagus nucleus
nucleus solitarius (caudal)
what is the somatic sensory nucleus of the vagus nucleus
sensory trigmeinal nucleus
what is the special sensory nucleus of the vagus nucleus
nucleus solitaries (rostral)
what is the main difference of the nucleus ambiggues in the glosso vs vagus n
in glosso: goes to stylophrageal
in vagus: goes to all other muscles of soft palate and pharybx and intrinsic laryngeal muscles
visceral motor information is carried by what nuclei for the glosso?
for the vagus
glosso: inferior slaivatory nucleus
vagus: dorsal motor nucleus
explain UMN control (corticonucleus) control of CN XI, and X
1) UMN in primary motor cortex (pre central gyrus, face area)
2) corona radiata
3) internal capsule (genu)
4) cerebral peduncle
5) synapse with LMN bilateral (in nucleus ambiguous)
for UMN control, where do UMN synapse with LMN for CN IX and X
in nucleus ambiguous bilateral
true or false, an UMN lesion unilaterally will have a big effect on the muscles of pharynx, larynx etc
false, it is receiving bilateral innervation
taste is carried by what cranial n
CN VII IX and X
taste from anterior 2/3 of tongue and soft palate is what CN
CN VII
CN VII carries taste from where
taste from anterior 2/3 of tongue and soft palate is what CN
taste from posterior 1/3 of tongue is what CN
CN IX
CN IX carries taste from where
posterior 1/3 of tongue
taste from epiglottis and soft palate is carried from what n
CN X
CN X carries taste from where
taste from epiglottis and soft palate
explain the pathway for cranial n and taste
1) primary sensory neurones project to nucleus solitarius (rostral)
2) secondary nueorns project to ventral posterior medial nucleus
3) tertiary neurons project to cortex (primary gustatory cortex in insula and parietal and frontal operculum)
what is the important thalamic nucleus for taste
ventral posterior medial nucleus (info coming from face)
where is the primary gustatory crotex
mostly in insula
also in parietal and frontal operculum (upper lip of lateral fissure(
CN X branchial motor component elevates the soft palate during what
phonation (speech)
CN X branchial motor component depresses the soft palate during what
swallowing
how can you detect a unilateral lesion of CN X
open mouth and phonate
=arch of soft palate will be dropped/flatteral on lesionied side (only able to elevate on unaffected side)
=deviation of uvula away from affected side
lesion to branchial motor component of left CN X will cause what symptoms
uvula deviates to contralateral side (deviate to right side)
left soft palate will droop during phonation
in a CN X lesion, the uvula will deviate towards what side with respect to lesion and wh
contralateral
(will be going towards the good side that is pulling it up)
in a CN X lesion, the palate will be drooping ipsilateral or contralateral to lesion during phonation
ipsilateral
what is the stimulant and where for the gag reflex
it is an irritant located on posterior tongue or upper pharynx
true or false, gag reflex involves only CN X
false, IX and X
explain afferent limb of the gag reflex
nociceptive signals travel via CN IX
=synapse in spinal trigeminal nucleus (somatic sensation) and caudal part of nucleus solitaries (visceral sensation)
in the afferent limb of gag reflex, the nociceptive signals are carried via what n
glosso
in the afferent limb of gag reflex, the nociceptive signals synapse in what two nuclei
=synapse in spinal trigeminal nucleus (somatic sensation) and caudal part of nucleus solitaries (visceral sensation)
the interneurons of the gag reflex project to what nucleus
nucleus ambiguous bilaterally
why do the interneurons project to nucleus ambiguous in the gag reglex
need to get the motor response of gagging
explain the primary efferent limb of gag reflex
CN X goes to muscles of pharynx and palate
what is the primary response of the gag reflex
elevation og the soft palate (open oral cavity to prevent it from going thry nano pahrynx)
closure of glottis (close respiratory system)
contraction of pharyngeal muscles to expel irritantw
what are the additional signals of the gag reflex
get signals that go to motor trigimeinal nucleus (CN V3 to open jaw) and hypoglossal nucleus (CN XII to protrude tongue )
add slides on lateral medullary syndrome)
