Oculomotor apparatus

The extraocular muscles provide movement of the eyeballs and determine human visual actions. The oculomotor system includes six muscles: four rectus muscles - the rectus ophthalmicus, superior oblique, inferior oblique, abductor and three indirect muscles - the levator palpebral muscle, the dilator pupillary muscle, and the inferior cutaneous muscle at the frontal pole. The canthal rectum, superior oblique and inferior oblique serve to rotate the eyeball; The abducens expands the field of vision when looking outward. In addition, the abductor muscles make additional movements that contribute to head rotation and chewing actions.