Horizontal cells

Horizontal cells are retinal interneurons in the outer plexiform layer. They receive input from photoreceptors (cones and rods) and provide lateral feedback and feedforward inhibition to photoreceptors and bipolar cells. This lateral inhibition creates the antagonistic center-surround receptive fields of bipolar and ganglion cells, which is fundamental for contrast enhancement, spatial sharpening, and color opponency in visual processing.