Lightness constancy: connectionist architecture for controlling sensitivity

Abstract

A simple yet biologically plausible neuronal architecture that can account for the phenomenon of lightness constancy is explored. The model uses a hierarchical structure of overlapping operators at multiple levels of resolution. All operators have receptive fields organized concentrically into two antagonistic zones of center and surround. This C/S organization allows the computing structure to adaptively adjust the thresholds without prior knowledge of the intensity distribution. The principal idea here is to have larger operators set the thresholds for smaller ones. Local and global averages are used to shift IR curves. The architecture is based on the simple principles of convergence, divergence, and inhibition. The result is a computationally robust, regular structure, which can simplify implementation in VLSI.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>