Muscles of the eye. Illustration of the human eye, showing the muscles (red) that control the movement of the eyeball and the upper eyelid. There are six extraocular muscles: the superior rectus, the inferior rectus, the lateral rectus, the medial rectus, the superior oblique, the inferior oblique and the levator palpebrae superioris (raises the upper eyelid). The rectus muscles run horizontally backwards from the top, middle and bottom of the eye. Other structures shown include the bulge of the cornea at the front of the eye, the iris and pupil.