Bipolar cells can respond in two general ways to incoming light. On bipolar cells exhibit different properties, and fire when less glutamate is released in response to light. Several photoreceptors converge upon a single bipolar cell to alter its firing rate. In addition, bipolar cells receive input from horizontal cells, which can also regulate the firing rate of the bipolar cell. In general, the influence of light in the surrounding field is opposite that of the direct effects of photoreceptors.
Ganglion cells receive input from bipolar cells and from amacrine cells.
When activated by bipolar cells in response to light, ganglion cells will depolarize to relay information to the CNS regions involved in visual processing. The response of the ganglion cell is greatly modified by the light impinging upon the surrounding receptive field. Ganglion cells that are activated by light on the receptive field will be suppressed if light also shines in the surrounding field. Thus the retinal ganglion cells are particularly responsive to changes in both the receptive field and the surrounding region. The retinal ganglion cells project to the brain through the optic nerve.