Which are the purely depolarizing cells in the optic pathway

Amacrine cells are inhibitory interneurons. They are purely depolarizing cells of the retina, they connect ganglion cells and sharpen the signal by lateral inhibition The responses of the rods, cones, and horizontal cells are hyperpolarizing, and the responses of the bipolar cells are either hyperpolarizing or depolarizing, whereas amacrine cells produce depolarizing potentials and spikes that may act as generator potentials for the propagated spikes produced in the ganglion cells. Ref: Ganong 25th ed/page 178