Assessment and treatment of automatically maintained hand mouthing in individuals with developmental disabilities

Research has shown that engaging in hand mouthing can be detrimental to an individual’s health, adaptive behavior, and social functioning, and interferes with participation in daily educational activities. Research also indicates that hand mouthing is most often maintained by automatic reinforcement (i.e., non-social contingencies). Functional analysis results have shown that automatically maintained behaviors may be differentiated (i.e., only occurs in the alone condition) or undifferentiated (i.e., occurs across all conditions), thus revealing two different classes of automatically maintained behavior. While numerous interventions have successfully treated hand mouthing, no studies have compared the effectiveness of a matched intervention across the two classes of automatically maintained hand mouthing. Therefore, the purpose of this study was to compare the effectiveness of a matched intervention across the two classes of hand mouthing in five individuals with severe to profound developmental disabilities. This was accomplished by performing functional analyses and preference assessments for each participant. A matched intervention was developed based on assessment results and focused on replacing the maintaining sensory stimulus of hand mouthing. The dependent measure was the percentage of intervals with hand mouthing, and data were analyzed using single-subject research designs. The matched intervention alone was effective at reducing the percentage of hand mouthing in four of the five participants. One participant required a more intensive intervention (i.e., matched intervention with DRO and blocking) to be implemented before decreases in hand mouthing were observed. Across the different patterns of behavior, the two participants with differentiated patterns showed immediate and durable decreases in hand mouthing. For the three participants with undifferentiated patterns of behavior, the intervention led to gradual decreases in hand mouthing, but for two of the three participants, the behavior was reduced significantly with the matched intervention. For the third participant with undifferentiated patterns, the matched intervention with DRO and blocking led to decreases in hand mouthing. The results, limitations, and future research will be discussed.