Light reflex pathway

Light shines in the right eye

Information travels along the ON, through the chiasm, and the temporal info goes to the ipsilateral pretectal nucleus; the nasal info travels to the contralateral pretectal nucleus

Both sides of the edinger-westphal nuclei are stimulated by both pretectal nuclei, since the visual information from one eye goes to both hemispheres at the chiasm

The Edinger- Westphal synapse with the ciliary ganglion (parasympathic) which follows the oculomotor muscles. This ganglion then sends action potentials to the sphincter to constrict both pupils