origin: anterior tubercles of transverse processes of the 3rd to 6th cervical vertebrae;
insertion: inferior surfaces of the basilar portion of the occipital.
- acting bilaterally, flexes cervical vertebrae and head;
- acting unilaterally, rotates and flexes cervical vertebrae and head to the same side;
nerve supply: muscular branches of C1, C2, C3, C4;
synergists: longus colli, sternocleidomastoid, scalenus group, suprahyoid, infrahyoid, and the platysma