Texture Perception

Abstract

An everyday texture judgment takes as input the image of a surface and produces a decision statistic gauging the surfaces suitability for a particular purpose (e.g., whether to trust a rock with ones boot while hiking). It is proposed that (1) human vision performs such judgments in real time through the use of a modest number of neural arrays, each of which measures the level at each point in the visual field of a distinct visual substance; and (2) human vision can only measure decision statistics produced by spatially averaging linear combinations of these visual substances. Research is reviewed whose purpose is to catalogue the substances of human vision. One case study is considered: the visual substance blackshot, so called because blackshot level reflects the density in a texture of only those texture elements of Weber contrast very near -1.0. Support for proposal (2) is derived from an experiment investigating attentional control of texture orientation judgments.