A Retinal Circuit Model Accounting for Functions of Amacrine Cells

In previous experimental studies on vertebrates, high level processes of vision such as object segregation and spatio-temporal pattern adaptation were found to begin at retinal stage. In those visual functions, diverse subtypes of amacrine cells are believed to play essential roles by processing the excitatory and inhibitory signals laterally over a wide region on the retina to shape the ganglion cell responses. Previously, a simple "linear-nonlinear" model was proposed to explain a specific function of the retina, and could capture the spiking behavior of retinal output, although each class of the retinal neurons were largely omitted in it. Here, we present a spatio-temporal computational model based on the response function for each class of the retinal neurons and the anatomical intercellular connections. This model is not only capable of reproducing filtering properties of outer retina but also realizes high-order inner retinal functions such as object segregation mechanism via wide-field amacrine cells.