Discrimination of simple objects decoded from the output of retinal ganglion cells upon sinusoidal electrical stimulation

Abstract Objective . Most neuroprosthetic implants employ pulsatile square-wave electrical stimuli, which are significantly different from physiological inter-neuronal communication. In case of retinal neuroprosthetics, use a certain type reliable object and contrast discrimination by implanted blind patients remained challenging. Here we investigated to what extent simple objects can be discriminated the output ganglion cells (RGCs) upon sinusoidal stimulation. Approach Spatially confined were formed combinations 1024 stimulating microelectrodes. The RGC activity in ex vivo retina photoreceptor-degenerated mouse, healthy mouse or primate was recorded simultaneously using an interleaved recording microelectrode array implemented CMOS-based chip. Main results We report that application stimuli (40 Hz) epiretinal configuration instantaneously reliably modulates spatially areas at low stimulation threshold charge densities nC mm −2 ). Classification overlapping but displaced (1° separation) achieved distinct spiking selected RGCs. A classifier (regularized logistic regression) (size: 5.5° 3.5°) with high accuracy (90% 62%). Stimulation artificial (10%) encoded stimulus amplitudes generated activity, classified 80% for large (5.5°). Significance conclude time-continuous smooth-wave provides robust, localized neuronal activation retina, may enable future vision temporal, spatial resolution.