The Computation of Lightness by the Primate Retina

Abstract

It is proposed that one function of the retina is to compute lightness using a two-dimensional parallel algorithm. There are three stages: (1) a centre-surround difference operation; (2) a threshold applied to the difference signal; (3) the inverse of (1), whose output is lightness. The operation of the midget bipolar—midget ganglion channel is analysed in detail, and a functional interpretation of various retinal structures is given. Requirements of the theory are stated concerning the arrangement and connexions of cells, and the signs of the synapses. in the inner plexiform layer.