Which nuclei does the light pupillary pathway synapse with?

In the light pupillary pathway, the primary function is to mediate the constriction of the pupil in response to light. This pathway begins when light enters the eye, stimulating photoreceptors in the retina. The neural signals are then transmitted through the optic nerve to the brain.

The first crucial synapse occurs in the pretectal nuclei, located in the midbrain. This region is responsible for processing visual information related to reflexive behaviors, including the pupillary light reflex. From the pretectal nuclei, the signal is sent to the Edinger-Westphal nucleus, which ultimately leads to the activation of the parasympathetic fibers that innervate the iris sphincter muscle, causing pupil constriction.

The other options provided are not involved in the light pupillary pathway. The lateral geniculate nucleus is primarily associated with visual relay pathways to the primary visual cortex and does not play a direct role in the pupillary reflex. The superior colliculus is involved in the integration of sensory information and the coordination of eye movements but does not synapse specifically for the pupillary response. The pineal gland is involved in secreting melatonin in response to light but is not a relay point in the light pupillary reflex pathway.