[1] Its fibers acquire their medullary sheaths early, but their connections have not been definitively determined.

Some are thought to be derived from the posterior part of the thalamus and from the superior colliculus, whereas others are believed to be continued downward into the medial longitudinal fasciculus.

For the pupillary light reflex, the olivary pretectal nucleus innervates both Edinger-Westphal nuclei.

To reach the contralateral Edinger-Westphal nucleus, the axons cross in the posterior commissure.

This article incorporates text in the public domain from page 812 of the 20th edition of Gray's Anatomy (1918)