Vagus Nerve (CNX) Flashcards
somatic sensation supplies?
external acoustic meatus
somatic motor supplies?
palate
pharynx
larynx
special sensation (taste) supplies?
epiglottis
visceral sensation supplies?
thorax
abdomen
visceral motor (parasympathetic) supplies
thorax
abdomen
course of CNX
leaves the medulla oblongata passes through jugular foramen with CNIX, CNXI and internal jugular vein.
passes posterior to root of the lung hilum to vagal trunks around the oesophagus
what branches does the CNX give off before passing posterior to the root of the lung hilum
superior laryngeal branch
recurrent laryngeal branch
three phases of deglutition (swallowing)
- oral phase (voluntary): mastication, bolus manipulation and labial seal
- pharyngeal phase (involuntary): hyolaryngeal elevation and sequential constrictor contraction
- oesophageal phase (involuntary): relaxation of UOS
what is the hard palate made up of?
left and right maxilla and palatine bones
contains palatal rugae
what supplies the hard palate?
pterygopalatine ganglion (secretomotor CNVII and general sensation CNV2)
nerve supply for the muscles of mastication
CNV3
innervation of the soft palate
CNX
how long should the pharyngeal phase take?
less than 1 second to switch from an air to a food channel, facilitated by elevation of soft palate to seal off nasopharynx
another name for cricopharyngeus
UOS (CNX)
location of the retropharyngeal space
between pre-vertebral fascia and pretracheal fascia
what can the retropharyngeal space cause?
spread of infection to the mediastinum
location of the parapharyngeal space
parallel to the outside of the pharynx (potential for asymptomatic tumours)
what does the pharyngeal plexus innervate?
muscles of the soft palate and pharynx, except tensor veli palatini
(sensory mucosa CNIX and CNX)
cough reflex afferent
CNX
describe steps in the cough reflex
- sensory stimuli in supraglottis
- glottic closure (lateral cricoarytenoid and arytenoid)
- internal and innermost intercostals and abdominal muscles contract
- glottic release high pressure air
articulation of oral sounds
- soft palate tenses CNV3 and elevates CNX to close nasopharynx
- direct stream of air through oral cavity
- sound interrupted by tongue CNXII and teeth and lips CNVII to produce vowels and consonants
articulation of nasal sounds
soft palate tenses CNV3 and descends CNX to close oropharynx
direct stream of air through nasal cavity
produce three sounds m, n or ing depending on tongue CNXII, teeth and lips CNVII
