A system includes means for providing an audio signal, a sound processor, a stimulation assembly comprising an array of LEDs, a driver unit for providing the simulation assembly with electric stimulation signals according to the auditory nerve stimulation signals, wherein the LEDs are arranged for optically stimulating the auditory nerve in the cochlea according to the electric stimulation signals, wherein the LEDs are connected to the driver unit in such a manner that, when the electric stimulation signal has a first polarity a first subgroup of the LEDs is active and a second subgroup of the LEDs is inactive, and when the electric stimulation signal has a second polarity opposite to the first polarity, the second subgroup of the LEDs is active and the first subgroup of the LEDs is inactive, and wherein the polarity of the electric stimulation signals is changed periodically.
