Optimizing stimulus parameters by modeling multi-electrode electrical stimulation for retina implants

The Purpose of this paper is to investigate the feasibility of retina implants to selectively stimulate individual retina neurons by coupled current pulses for multielectrode arrays. Retina implants with learning retina encoders [3], [4] for blind subjects suffering from retinal degeneration must be able to stimulate individual retinal nerve cells. A computer model of a retina segment was combined with the simulation of a set of epi-retinally positioned stimulation electrodes. The potential field distribution was calculated for a cluster of neighboring electrodes. Stimulus time courses for given geometric conditions were identified by direction set methods as well as evolutionary algorithms. The computational retina model reveals under which conditions different retinal nerve cells are stimulated.