The invention relates to an implant which includes, in order to electrically stimulate a nerve structure, in particular the retina, an electrically insulating substrate (1), a network of recesses (2) formed in an upper surface of the substrate, stimulation electrodes (3) arranged at the bottom of the recesses, and an electrically conductive layer forming a floorplan (4) at the upper portion of the recesses. The sizes of the recesses and of the electrodes of the implant are such that the spatial selectivity of the stimulation current applied to the nerve structure are maximised.
