Modifiability of Preattentional Processes
Michael Carlin

Funded by NICHD, ROI HD36832

Preattentional processing refers to the early stages of visual processing that operate prior to cognitive or attentional influence. The importance of these early stages of visual processing lies in the fact that their outputs serve as the basis for perception and cognition. If the preattentive processes of individuals with and without mental retardation do not operate identically, then the higher processing centers will not receive identical input. The differential input for attentional processing would be expected to have dramatic and widespread consequences for behavior. Several recent studies have indicated that individuals with mental retardation do not process visual stimuli preattentively in the same manner as individuals without mental retardation. Such differences have been identified across experimental tasks as varied as visual search and detection of motion-defined forms. These findings, if found to be reliable and general, would have import for theoretical discussions of the bases for intelligence-related differences on various experimental tasks, as well as applied relevance for the design of optimal learning environments and training procedures. This project assesses the extent to which intelligence-related differences at this basic level of visual processing are modifiable. The specific goals of the project are to: (a) compare the visual search modes of individuals with and without mental retardation, (b) determine structural manipulations of visual arrays that can increase efficiency of search, (c) determine the mechanisms underlying intelligence-related differences on preattentional tasks, (d) design training procedures to minimize differences between individuals with and without mental retardation, and (e) investigate applications of basic research on preattentional processing to more applied tasks (e.g., matching to sample). The latter goals represent a bridge between cognitive psychology and concerns of behavior analysts. We hope to utilize knowledge of preattentional processing and task structure to develop intervention procedures that can rapidly induce observation of critical elements in visual arrays such that control can be established and learning can take place. We are particularly concerned with producing methods for rapidly establishing matching to sample skills and arbitrary relations among stimuli (e.g., picture-word, spoken word-written word).