Decoding the roles of bipolar, amacrine, and horizontal cells.

The retina consists of several specialized cell types, crucial for visual processing. Bipolar cells, amacrine cells, and horizontal cells are retinal interneurons, playing pivotal roles in transmitting and modulating visual information within the retina. In this chapter, we first highlight the significance of bipolar cells in relaying signals from photoreceptors to ganglion cells, initiating visual signaling. Recent consensus indicates the existence of different types of bipolar cells in various species, leading us to focus on their functional diversity and morphologic characteristics. Second, we explore many types of amacrine cells and their roles in lateral inhibition, modulating signaling between bipolar cells and ganglion cells. Lastly, we examine the structure and function of horizontal cells in providing feedback inhibition to cones, regulating light sensitivity and color processing. Structural analysis of retinal neurons over the decades has revealed that complicated retinal neural networks are the crucial component for signal processing in the visual system. Such insights are essential for understanding the mechanisms underlying visual perception and pathology, developing future therapies for retinal diseases, and advancing artificial vision technologies.