As these muscles pass forward in the orbit to attach to the anterior half of the eyeball, they are also directed laterally (Fig. 8.95). Because of these orientations:
Contraction of the superior rectus elevates, adducts, and internally rotates the eyeball (Fig. 8.97A).
Contraction of the inferior rectus depresses, adducts, and externally rotates the eyeball (Fig. 8.97A).