Physiological engineering model of the retinal horizontal cell layer

A model of the L-type horizontal cell layer in the retina was constructed in terms of the soma, axon terminal and gap junction to understand its spatiotemporal properties. The soma and axon terminals were expressed by the Hodgkin-Huxley-type equations based on the relevant ionic currents. The cell layer was simulated by connecting each L-type horizontal cell model with a linear gap junction. While the model response explained the experimental data considerably well, the dynamical features were not fully realized without a feedback path from the horizontal cells to the photoreceptors. The nonlinear dynamical characteristics, which were considered to reside in the gap-junctional conduction in the model, explained the nonlinear feature observed in the response waveform to various light stimulus configurations.<>