Translations:The Eye and Retina/35/en
From Eyewire
Horizontal Cell Feedback
While horizontal cells represent a small portion of the retina, they do form many synapses with the photoreceptors. One of the leading theories on the function of horizontal cells is to increase the contrast between the light and dark regions. The horizontal cells will inhibit the signal of an excited cone and the cones surrounding it. While this dampens the signal, it also eliminates the signal from surrounding cones that aren't excited, so only the ganglion cells associated with the excited cone will be excited, rather than all the ganglion cells of the cone and its neighbors.
