Muscles of Voice Flashcards
what do the muscles of the larynx act to do?
sphincter mechanism
control vocal cord allowing air to pass and preventing aspiration
where is the air forced through in the vocal cords?
rima glottidis which vibrates the vocal cords producing sound
what are all the intrinsic muscles supplied by?
inferior laryngeal branch of CNX, except cricothyroid which is supplied by superior laryngeal nerve
role of the lateral cricoarytenoid muscle
adducts vocal ligaments
role of the posterior cricoarytenoid muscle
abducts vocal cords
role of the thyroarytenoid muscle
relaxes vocal ligament
role of the arytenoid muscle (two bands- oblique and transverse)
adducts vocal ligaments
role of the cricothyroid muscle
tenses vocal ligament
describe the phonation function of the larynx
inspiration and controlled expiration builds pressure inferior to the larynx (subglottal pressure)
air crosses the vocal cord causing vibration
length and tension dictates pitch and degree of opening of the rima glottis
what does tension on the vocal cords cause?
increased pitch (high voice)
what does relaxation on the vocal cord cause
decreased pitch (low voice)
what does adduction on the vocal cord cause?
quieter sounds
what does abduction on the vocal cords cause?
louder sounds
what are all the muscles of voice innervated by?
CNX, except cricothyroid (superior laryngeal branch)
what does lateral cricoarytenoid do to voice?
quiet sounds
