| Abstract: Behaviors maintained through automatic reinforcement make it difficult to treat as the source of the maintaining variable may not be readily available for manipulation. One such behavior is automatically-reinforced vocal stereotypy (VS) which is defined as idiosyncratic, non-functional vocalizations. Vocal stereotypy occurs in various populations however, it is most often observed in individuals with autism spectrum disorder (ASD) where it becomes problematic if it occurs at high rates and interferes with socialization or functioning in structured settings. There are multiple effective interventions available in the literature, however, many procedures require high rates of interventionist time and target complete omission of the behavior which may be problematic in applied settings. One intervention which has not been assessed as an individual intervention in the automatically-reinforced VS literature is differential reinforcement of low rates (DRL). In the present study, a functional analysis was used to determine that the VS of two female adolescents with ASD was maintained by automatic reinforcement. A DRL procedure was implemented which incorporated: (a) a specified interval for reinforcement, (b) the permissible number of VS acceptable within the interval, (c) a behavior checklist, and (d) learner feedback. As the targeted behavior decreased across sessions, the DRL interval was systematically increased in order to thin out the schedule of reinforcement. The intervention reduced VS and increased untargeted task engagement in both participants. Applied and theoretical implications of the study, as well as ethical considerations, social validity, limitations, and future research are discussed. |