اثرات عوامل تقویت مثبت و منفی به صورت همزمان بر روی پذیرش و مشکلات رفتاری

Functional analysis (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994) is a robust approach to identifying function-based interventions for problem behavior, including self-injury, aggression, and destruction. Such interventions, however, may be difficult for untrained caregivers to implement with fidelity in natural environments. Further research is needed to identify simple antecedent strategies for promoting appropriate behavior among children with significant problem behavior. The purpose of the current study was to utilize a concurrent schedules arrangement to identify conditions under which two children with autism spectrum disorder (ASD) and developmental delays who engaged in problem behaviors would choose to complete academic tasks to earn access to preferred items. In both cases, problem behaviors were shown to be sensitive to reinforcement in the forms of escape from task demands and access to preferred items. A concurrent operant arrangement in which the participants could choose to complete work tasks to earn access to preferred activities, or to take a break without demands or preferred items, was implemented. The schedule requirements in the demand component were systematically increased across opportunities, while the amount and type of reinforcement was kept constant. The results show, at the lowest levels of task demands, both participants allocated more opportunities to the work option. At higher levels, however, both participants allocated a majority of their choices to the break option. Despite the absence of preferred items in the break component, no instances of problem behavior were observed following selection of the break option. This indicates that this type of analysis could be used to identify conditions for compliance among individuals who engage in escape- or multiply-maintained problem behaviors, without the need to provoke or reinforce problem behavior. Limitations of the current study and recommendations for future research are discussed.

Functional analysis (Iwata, Dorsey, Slifer, Bauman, & Richman, 1982/1994) permits identification of functional relations between problem behavior, including self-injury, aggression, and destruction, and its consequences. Determining the function of problem behavior, in turn, facilitates altering the relevant reinforcement contingencies to decrease problem behavior and increase appropriate behavior (Steege, Wacker, Berg, Cigrand, & Cooper, 1989).For example, treatment for negatively reinforced behavior often includes escape extinction, reinforcement of alternative, appropriate behavior (contingent on alternative behavior or noncontingent), or a combination of both (e.g., DRA, DRO; Vollmer, Marcus, & Ringdahl, 1995; Wacker et al., 1990). With any intervention, its effectiveness depends on the fidelity with which it is implemented. Consequence-based interventions such as extinction or differential reinforcement may be particularly difficult for parents, teachers, or other caregivers to implement with adequate fidelity, especially if the target behavior is frequent or of such severity that it is challenging or impossible to ignore. When the problem behavior includes aggression or self-injury, procedures that might produce a side effect such as an extinction burst may be inappropriate. However, research has shown also that positive reinforcement in the form of access to preferred items or activities, can be effective for improving problem behavior that is maintained by negative reinforcement or multiple functions (i.e., positive and negative reinforcement) (Payne & Dozier, 2013). Importantly, the effectiveness of positive reinforcement for reducing negatively reinforced and increasing appropriate behavior has been demonstrated even in the absence of extinction (Lalli et al., 1999). One strategy that shows promise in assessing the effects of access to preferred items or activities on behaviors maintained by negative reinforcement is the use of concurrent schedules. Several studies have used concurrent schedules to examine the effects of manipulations of both positive and negative reinforcement on problem behavior and task completion. For example, Golonka, Wacker, Berg, Derby, Harding, and Peck (2000) provided two participants with negatively reinforced problem behavior to choose between continued work or taking a break during demanding tasks. In an alternating treatments design, the effects of providing access to preferred items during the break (combined negative and positive reinforcement condition) were compared to the effects of a break without preferred items (negative reinforcement alone). The combined condition resulted in greater reductions in problem behavior and increases in appropriate requesting. Nevertheless, escape extinction was necessary to increase completion of task demands without problem behavior for both participants. Similarly, Piazza, Fisher, Hanley, Remick, Contrucci, and Tammera (1997) compared the effects of negative reinforcement with combined positive and negative reinforcement, with and without extinction. Three participants with multiply maintained problem behavior participated. They demonstrated that, for two participants, providing breaks with preferred items contingent on appropriate behavior was effective for decreasing problem behavior and increasing compliance without escape extinction. For the final participant, however, escape extinction was necessary. When the schedule of reinforcement for appropriate behavior was faded, escape extinction and access to multiple reinforcers for appropriate behaviors were necessary for optimal results for all participants. Finally, Hoch, McComas, Thompson, and Paone (2002) used a concurrent schedules arrangement to evaluate the effects of positive and negative reinforcement without extinction on the behavior of three children with autism whose problem behavior was maintained at least in part by negative reinforcement. They demonstrated that problem behavior was eliminated and task completion increased when problem behavior produced a break from task demands and task completion produced a break with access to preferred activities. These results were maintained even when the response requirement was increased and the schedule of reinforcement was thinned. Overall, these results indicate that combining positive and negative reinforcement may be more effective than either form alone for decreasing problem behavior and increasing compliance. In many cases, however, escape extinction was necessary to achieve optimal results. One possible reason for this pattern is that participants in these studies were required to complete a certain amount of a difficult task in order to get access to an opportunity to escape from the task. One alternative strategy could be to provide opportunities for individuals to avoid the task entirely by presenting choice opportunities prior to presentation of task demands. In this case, escape or avoidance are always available for appropriate behavior (choice making), which reduces the likelihood of problem behavior. On the other hand, by manipulating the quantity or difficulty of the work presented, or the quantity or quality of the reinforcement available for task completion, it should be possible to bias the individuals’ responding away from escape/avoidance and toward task completion. In the current study, we evaluated the effects of positive reinforcement on the amount of work completed by two children with autism spectrum disorder (ASD) and developmental delays who engaged in problem behaviors maintained by escape from demands and access to tangible items (i.e., negative and positive reinforcement). We created a concurrent operant arrangement in which two response options were presented prior to the initiation of any difficult task demands: (a) negative reinforcement in the form of escape contingent on a request for a break, and (b) positive reinforcement in the form of access to a highly preferred edible item contingent on completing a pre-determined and signaled amount of work. Across trials, the amount and type of reinforcement available remained constant, as did the alternative option (break contingent on a request). A progressive-ratio schedule was implemented in which the schedule requirements for the positive reinforcer increased after each session in order to identify the highest number of work tasks that each participant would choose to complete in order to gain access to the preferred items.