Differentiating Color Responses in Retina Through Multielectrode Array Recordings

The retina mediates vision while encoding various features of a visual such as brightness, color, motion, direction, etc. An epiretinal prosthesis, directed towards restoring vision in the blind, intend to incorporate these parameters in the input stimulus. The output neurons of retina, retinal ganglion cells (RGC), convey the perceptible information to the brain. The wavelength information of primary colors received by the cones are expected to have characteristic features in RGC responses before being perceived by the brain. Thus responses from the RGCs are recorded with multielectrode array (MEA) and analyzed to distinguish between light stimulus of different wavelengths. Two major types of neurons with opposite polarity were identified for each color and their spiking nature was studied. A spontaneous response was also detected for all the colors. Red, blue and green were uncorrelated with white light stimulus which clearly indicates wavelength information can be decoded from multineuronal recordings from RGCs. These information can be encoded in electric stimulus for prosthetic vision development.