Biomimetic Stimulating Array for Single Localized Stimulation in Visual Prosthesis

Visual prostheses electrically stimulate nearby neurons to generate artificial vision in patients blinded by retinal degenerative diseases. Current prosthetic devices offer limited spatial resolution that results in unselective stimulation of ganglion cells and the generation of percepts with shapes other than a small spot of light. In this study, we introduce a theoretical approach to treat the biomimetic retinal electrode array. This array produces electrodes that are self-determined to adjust their spatial parameters for single localized stimulation. Electrode stimulation of the biomimetic electrode array was simulated in a 3D reconstruction of the retina and ganglionic layer at locations in the retina with high area cell density. We also simulated ganglion cell stimulation in the far periphery as the array could be relocated on the retina due to the natural movements of the eye. Single localized stimulation was achieved throughout the retinal regions near the fovea, which is required in humans for activities where visual detail is of primary importance and thus relevant for high resolution vision. Single-cell stimulation responses leveled off until 30° of eccentricity in average using the biomimetic array with large array area. That is, the biomimetic array can produce a stable stimulation of single cells and a broad field of view for a wide region of the retina. Lastly, we provide considerations for the biomimetic electrode array for practical applications. Together of being useful to improve single cell activation, the applicability of the biomimetic electrode array can yield strategies to increase the area of the array and produce a wide-ranging field of view.