Intrinsic and extrinsic tongue muscles Flashcards
What are the intrinsic tongue muscles?
transverse, vertical, superior longitudinal, and inferior longitudinal
What cranial nerve innervates the intrinsic tongue muscles?
hypoglossal nerve (XII)
What does the superior longitudinal muscle do?
it elevates the tongue, and, if contracted at the same time as the inferior longitudinal muscle, helps retract the tongue
What does the inferior longitudinal muscle do?
Pulls the tip of the tongue downward and helps retract the tongue only if it is contracted at the same time as the superior longitudinal muscle.
What does the transverse muscle do?
narrows the tongue, pulling the edges toward the midline
What does the vertical muscle do?
it pulls the tongue to the floor of the mouth
What are the extrinsic tongue muscles?
hyoglossus, styloglossus, palatoglossus, chondroglossus, and genioglossus
All extrinsic tongue muscles except for the palatoglossus muscle are innervated by
hypoglossal nerve (CN XII)
What CNs innervate the palatoglossus muscle?
accesory nerve (CN XI) and vagus nerve (CN X)
What does the palatoglossus muscle do?
brings the tongue up and depresses the palate
What does the chondroglossus muscle do?
bring the tongue down
What does the styloglossus muscle do?
draws the tongue up and back
What does the hyoglossus muscle do?
pulls side of the tongue down
What does the genioglossus muscle do?
the main mover of the tongue; anterior fibers pull the tongue back and the poster fibers pull the tongue out when contracted
What happens to the tongue when the anterior and posterior fibers of the genioglossus muscle contract?
it pulls the middle of the tongue down to the roof of the mouth
