Effect of Background Constraint on Visual Search Times

Abstract

Search backgrounds used previously with human subjects ranged from regular arrays of nontargets differing from the target in only one dimension through to irregular arrays of nontargets differing from the target in many dimensions (size, shape, color and contrast). There is no basis for comparison among results of these search tasks. In the experiment described, statistically determined displays differing in the probability of transition (Pt) from the state dot present to dot absent were used as search backgrounds and the relation between search time and Pt was determined. Pt may be useful in describing applied search task backgrounds.