The Effect of Command Preexposure on Instruction-Following Behavior in Severely Retarded Adolescents

Abstract

Repeated nonreinforced preexposure of a stimulus subsequently used as a conditioned or discriminative stimulus typically results in a decrement in performance of infrahumans and humans in classical and instrumental conditioning tasks. The naturalistic or applied significance of this “latent inhibition” phenomenon has not been investigated. This study examined the effects of repeated presentations of verbal commands on the acquisition of instruction-following behavior in two severely retarded girls. Each received 200 preexposures of one command followed by instruction-following training on both the preexposed and a nonpreexposed command. This procedure was repeated for three different pairs of commands for each girl. Commands were given in French and preexposed and nonpreexposed commands were counterbalanced across subjects. Mean percentage of unassisted responses to preexposed commands was 35.9 percentage points less than to nonpreexposed commands on the first day of training. The results suggest that latent inhibition may be a viable phenomenon in applied settings.