Retinal representation of the elementary visual signal

The propagation of visual signals from individual cone photoreceptors through parallel neural circuits was examined in the primate retina. Targeted stimulation of individual cones was combined with simultaneous recording from multiple retinal ganglion cells of identified types. The visual signal initiated by an individual cone produced strong responses with different kinetics in three of the four numerically dominant ganglion cell types. The magnitude and kinetics of light responses in each ganglion cell varied nonlinearly with stimulus strength but in a manner that was independent of the cone of origin after accounting for the overall input strength of each cone. Based on this property of independence, the receptive field profile of an individual ganglion cell could be well estimated from responses to stimulation of each cone individually. Together, these findings provide a quantitative account of how elementary visual inputs form the ganglion cell receptive field. "Visual stimulation was targeted to individual cone photoreceptors in primate retina"Multiple retinal ganglion cell types respond robustly to stimulation of a single cone"Responses in a given ganglion cell are univariant with respect to the cone of origin"Linear approximations of ganglion cell receptive fields predict single-cone responses Li et al. combine targeted visual stimulation of individual cone photoreceptors with simultaneous recording from multiple ganglion cells of identified types in primate retina, providing a quantitative account of how elementary visual inputs form the ganglion cell receptive field.