Walsh & Hoyt: The Afferent Arc of the Pupil Light Reflex

The neuronal integration of the pupillary light reflex begins in the retina with the photoreceptors that pass information to the retinal ganglion cells by way of synapses with bipolar cells. For many years, it was assumed that only the photoreceptors contributed to the pupillary light reflex. It is now clear that other retinal elementsparticularly certain ganglion cellsalso play a role. Rod and cone contribution to the pupillary light reflex. Retinal ganglion cell contributions to the pupillary light reflex. Contributions from ganglion cells in general. Contributions from melanopsin-containing photoreceptive ganglion cells.