Both rod cells and cone cells synapse with bipolar cells, short sensor neurons that transfer impulses to a second set of sensor neurons, the ganglion cells. The ganglion cells' axons bundle together to form the optic nerve which, then, carries the impulses to the brain's visual center. Yet, visual impulses begin being processed even before the impulses leave the eye. The convergence of information that occurs during the series of synapses between receptors and bipolar cells and between bipolar cells and ganglion cells helps the retina begin processing the received information. Two other sets of cells also help the retina begin processing the received information. The horizontal cells synapse with both bipolar cells and receptor cells as well as with other horizontal cells. The amacrine cells synapse with both bipolar cells and ganglion cells as well as with other amacrine cells. The horizontal and amacrine cells, thus, help create a lateral transference of information among the different parts of the retina itself.
