Stimulus control of self-destructive behavior in a psychotic child

This study attempted to isolate some of the stimulus variables that controlled the self-destructive behavior of a psychotic child. In Experiment 1, the child was exposed to several demand and nondemand situations. In Experiment 2, the situation containing demands was modified so that demands now occurred in the context of a positive, ongoing interaction between the child and the adult therapist. The rates of self-destructive behavior underwent several orderly changes: (1) Rates were high in demand situations and low in nondemand and modified-demand situations; (2) rates decreased sharply when a stimulus correlated with the termination of demands was introduced; and (3) rates of self-destruction typically showed gradual increases within each of those sessions which contained only demands. These results were interpreted as suggesting that (1) self-destruction, under certain circumstances, may be conceptualized as an escape response which is negatively reinforced by the termination of a demand situation and (2) certain modifications of the social environment may provide discriminative stimuli for behaviors other than self-destruction, thereby decreasing this behavior.This investigation was supported in part by USPHS Research Grant 11440 from the National Institute of Mental Health. The research was conducted while the first author held a postdoctoral fellowship from the Medical Research Council of Canada. The authors thank Jon and Lynn Killion and Dennis Russo for their help in data collection and Ivar Lovaas, Laura Schreibman, and Robert Koegel for their many helpful criticisms. The encouragement and support of Tim's parents during the course of this study are sincerely appreciated.