CN IX, X, XI, XII Flashcards
at what level of the brainstem would you find the hypoglossal nucleus
rosrtal medulla
what is the function of CN XII
tongue protrusion of the genioglossus (tongue) muscle
what would happen if there was a lesion in the hypoglossal (lower motor neuron) nerve
- tongue deviates ipsilaterally to lesion
- fasiculations
- atrophy
what is the upper motor neuron sending signals to the hypoglossal nucleus
corticobulbar fibers
what would happen if there was a lesion in the corticobulbar pathway (upper motor neuron) with regards to CN XII
- tongue would deviate contralaterally (cuz decussates adjacent to hypoglossal nucleus)
- no fasiculations
- no atrophy
CN XII is what type of nerve ?
somatic efferent (motor)
CN XI is what type of nerve ?
brachial motor
what muscles does CN XI innervate
SCM, trapezius
what would the effect be on the trapezius m. if there was an injury to CN XI
paralyzed trapezius causing
- scap and clavicle hang
- weak shoulder shrug
- atrophy leading to scalloped neck
the somatic sensory portion of CN IX recieves impulses from where ? and then synapses where ?
skin of outer ear to
- spinal trigeminal nucleus
- superior ganglion of IX
the visceral sensory portion of CN IX recieves impulses from where ? and then synapses where ?
post. 1/3 taste buds and mucosa, carotid body and sinus, pharynx/oropharynx and middle ear to
- nucleus of solitory tract
- inferior ganglion of IX
the visceral motor of CN IX has origins where, and sends efferent to ?
inferior salivatory nucleus to otic ganglion to parotid gland
the brachial motor of CN IX has origins where and sends efferents to ?
nucleus ambiguus to stylopharyngeus (muscle of pharynx)
the nucleus ambiguus deals with motor or sensory input, specifically what muscle ?
motor to stylopharyngeus
what CN all have sensory input on the outer ear ?
CN VII, IX, X
changes in blood pressure would be sensed where ?
carotid sinus
changes in blood O2, CO2, or pH levels would be sensed where ?
carotid body
what ganglia/nuclei are involved with the carotid body and carotid sinus
inferior ganglion of IX and solitary nucleus
what is glossopharyngeal neuralgia
sudden burst of pain starting in post. 1/3 of tongue or pharynx then spreading to ear
where is the trigger zone for glossopharyngeal neuralgia
tongue/pharynx
attacks of glossopharyngeal neuralgia are precipitated by ?
swallowing or coughing
somatic sensory for CN X has inputs from where, and then synapses where ?
skin of outer ear to
- spinal trigeminal nucleus
- superior ganglion of X
visceral sensory for CN X has inputs from where, and then synapses where ?
taste buds of epiglottis and esophagus, also pain and temp from thorax, abdominals, mucosa of larynx/pharynx
- solitary nucleus
- spinal trigeminal nucleus
- inferior ganglion of X
nucleus ambigus has cell bodies for what CN ?
IX, and X
what CN exit the skull at the jugular foramen
IX, X, and XI
visceral motor for CN X originates where and sends efferents where ?
dorsal motor nucleus and nucleus ambigus to
-thoracic and abdominal viscera
brachial motor of CN originates where and sends efferents to where ?
nucleus ambigus to
- larynx pharynx laterally
- heart and lungs medially
what CN are involved with the spinal trigeminal nucleus
V, IX, X
what CN are involved with the nucleus of the solitary tract
VII, IX, X
what is the afferent and efferent limb of the gag reflex
afferent - CN IX
efferent - X
what is the afferent and efferent limb of the tongue thrust reflex
afferent - CN V or IX
efferent - CN XII
what is a vasovagal syncope
loss of consciousness due to vagus triggering decrease in heart rate, blood pressure, and cererebral flow
what nerves are at risk of entrapment by a skull base tumor in jugular foramen syndrome
IX, X, XI, XII
what are some of the major symptoms of jugular foramen syndrome
- palate droops
- wasting of tongue
- oropharyngeal sensory loss,
- uvula deflects contralateral to lesion
- atrophy of SCM and trapezius
