AN ANALYSIS OF THE REINFORCING PROPERTIES OF HAND MOUTHING

Hand mouthing often has been described as a stereotypic response that is maintained by nonsocial (automatic) reinforcement; however, data su pporting this conclusion can be found in relatively few studies. This series of studies presents an experimental analysis of conditions asso ciated with the maintenance of hand mouthing. In Experiment 1, a funct ional analysis was conducted for 12 individuals who engaged in chronic hand mouthing to determine whether the behavior is usually maintained independent of social contingencies. Results obtained for 10 subjects were consistent with an automatic reinforcement hypothesis; the remai ning 2 subjects' hand mouthing was maintained by social-positive reinf orcement. Based on these results, Experiment 2 was designed to identif y the specific reinforcing properties of hand mouthing. Each of 4 subj ects was provided with a toy that substituted for hand mouthing, and p reference for a specific topography of toy manipulation (hand-toy cont act or mouth-toy contact) was measured. Results indicated chat hand st imulation was the predominant reinforcer for all subjects. Experiment 3 provided an extension of Experiment 2 in that the same responses wer e measured across a variety of toys presented to each of 5 subjects. R esults again indicated that hand stimulation was the predominant reinf orcer for all subjects. Implications of these results are discussed wi th relevance to treatment.