Spatiotemporal organization of the receptive fields of retinal ganglion cells in the cat: a phenomenological model.

The reorganization of ganglion cell receptive fields (RFs) with different levels of light adaptation was investigated by means of spontaneous contour planes (SCPs). The SCP shows the spatiotemporal characteristics of the cell responses to a small bar of light switched on and off at 31 separate points along the RF horizontal axis. We assume a radial symmetry of RFs. A mathematical function describing the SCPs and their light level induced changes was found. Its form suggests that three mechanisms (central, surround and phasic) are required to account for RF organization of both homogeneous and heterogeneous retinal ganglion cells. The phasic component is probably identical with the nonlinear mechanism described by other authors. Responses to moving stimuli .were also investigated and correlated with the spatiotemporal organization of the RF.