ارزیابی ترجیحات برای تقویت مثبت و منفی در طول درمان رفتار مخرب با آموزش برقراری ارتباط عملکردی

Results of prior studies (e.g. [J. Appl. Behav. Anal. 32 (1999) 285]) showing that participants chose alternative behavior (compliance) over escape-reinforced destructive behavior when this latter response produced escape and the former response produced positive reinforcement may have been due to (a) the value of the positive reinforcer overriding the value of the negative reinforcer or (b) the presence of the positive reinforcer altering the value of the negative reinforcer (i.e., lessening the aversiveness of the demands). In this investigation we evaluated the relative contributions of these alternative mechanisms with two girls with autism. We compared the relative effects of positive and negative reinforcement using equivalent communication responses under both a restricted-choice condition (in which participants could choose positive or negative reinforcement, but not both) and an unrestricted-choice condition (in which participants could choose one or both reinforcers). Both participants often chose positive over negative reinforcement in the restricted-choice condition. However, in the unrestricted-choice condition (in which participants could choose one or both reinforcers), one participant consistently chose both reinforcers by the end of the analysis whereas the other primarily chose only positive reinforcement. Results suggested that for one participant the value of the positive reinforcer overrode the value of the negative reinforcer, whereas for the other participant, the presence of the positive reinforcer in the demand context lessened the aversiveness of the demands.

The approach to the treatment of aberrant behavior that is increasingly becoming the standard of care begins with a functional analysis to identify the reinforcer(s) for the response, which then leads to treatments that generally manipulate that reinforcer in ways that decrease the problem behavior. For example, a common approach to the treatment of aberrant behavior maintained by negative reinforcement is to eliminate the escape contingency that was shown to reinforce the response during the functional analysis, a treatment referred to as escape extinction (EE; Iwata, Pace, Kalsher, Cowdery, & Cataldo, 1990; Kelley, Piazza, Fisher, & Oberdorff, 2003). Although EE is generally effective as treatment for aberrant behavior maintained by escape, it is sometimes associated with negative side effects (e.g., bursts of the target behavior, induction of aggression or negative vocalizations; Goh & Iwata, 1994; Lerman & Iwata, 1996; Lovaas, Freitag, Gold, & Kassorla, 1965; Piazza, Patel, Gulotta, Sevin, & Layer, 2003). A variety of procedures have been combined with EE in order to lessen the negative side effects, including differential positive reinforcement of alternative behavior (DPRA; Patel, Piazza, Martinez, Volkert, & Santana, 2002), differential negative reinforcement of alternative behavior (DNRA; Marcus & Vollmer, 1995), noncontingent reinforcement (Fisher, DeLeon, Rodriguez-Catter, & Keeney, 2004; Vollmer, Marcus, & Ringdahl, 1995), or stimulus (or demand) fading (Pace, Ivancic, & Jefferson, 1994), but bursts may still occur (see Lerman & Iwata for a discussion). Another promising approach to the treatment of aberrant behavior maintained by negative reinforcement involves the identification of potent positive reinforcers that are then placed in direct competition with the escape contingency for problem behavior through DPRA (without extinction; Adelinis, Piazza, & Goh, 2001; DeLeon, Neidert, Anders, & Rodriguez-Cater, 2001; Lalli, Casey, & Kates, 1995; Lalli et al., 1999 and Piazza et al., 1997). If the individual consistently chooses the positive reinforcer associated with the alternative response over the negative reinforcer associated with problem behavior, then EE becomes unnecessary. But even if the individual chooses the positive reinforcer over the negative reinforcer some of the time (and the alternative response increases), then EE will generally be implemented less often. Using this approach, Piazza et al. showed that the destructive behavior displayed by three participants was reinforced by escape (as well as positive reinforcement). For one participant, providing the same escape contingency for alternative behavior (compliance) and destructive behavior increased the alternative response and decreased destructive behavior to near-zero levels. For the other two participants, destructive behavior maintained at high rates when both responses produced escape. However, destructive behavior decreased with these latter two participants when the alternative response produced a break with access to positive reinforcement whereas destructive behavior only produced escape. A limitation of the Piazza et al. (1997) study was that it was unclear in these latter two cases whether it was necessary to provide escape for the alternative response or whether reinforcing this response only with positive reinforcement would have produced similar reductions in destructive behavior. Lalli et al. (1999) addressed this limitation with five participants who displayed escape-reinforced problem behavior. These investigators reinforced the alternative response (compliance) with positive reinforcement (food) while the escape contingency remained intact. That is, when participants displayed destructive behavior, they received a 30 s break, whereas when they displayed the alternative response, food was delivered and the presentation of demands continued. In all five cases, destructive behavior decreased and the alternative response increased when the alternative response produced positive reinforcement and destructive behavior produced escape relative to when both responses produced the same negative reinforcer (i.e., escape for 30 s). Lalli et al. (1999) suggested that their findings might be explained in terms of the principles of choice responding wherein the alternative response and destructive behavior were concurrent operants and the participants’ motivation for food was often greater than their motivation for escape, and thus they frequently emitted the response (compliance) associated with food. With this explanation, the value of escape was not altered; rather, its value was momentarily overridden by the value of food (i.e., the demands were tolerated, and compliance was emitted during most trials in order to get the food). An alternative explanation was also briefly mentioned by Lalli et al. (see the last paragraph of Section 3), one in which the presence of positive reinforcement acted as a motivating operation (MO) that momentarily altered (i.e., abolished) the value of escape and thus decreased its effectiveness as negative reinforcement for destructive behavior (Laraway, Snycerski, Michael, & Poling, 2003).1 Lalli et al. presented these two explanations as alternatives (reductions in problem behavior due to positive reinforcement overriding versus altering the value of escape), but its possible that one or both are operative with different children. It may be important to distinguish between these two alternative explanations for the effects of competing positive reinforcement on escape-reinforced problem behavior, because if problem behavior decreases solely because the positive reinforcer overrides the negative reinforcer, then one might expect destructive behavior to increase over time. That is, the participants may eventually learn that by displaying both the alternative response and then destructive behavior, it is possible to obtain both reinforcers, which would result in an increase in problem behavior. By contrast, if the presence of the positive reinforcer altered rather than overrode the value of the negative reinforcer, then destructive behavior should remain relatively low. In the current investigation we attempted to separate the effects of these two mechanisms (the positive reinforcer overriding v altering the value of the negative reinforcer) with two girls with autism. We compared the relative effects of positive and negative reinforcement using equivalent and novel communication responses under two choice arrangements. We used equivalent and novel communication behaviors as the operants to eliminate the potential effects of response bias (cf. DeLeon, Fisher, Herman, & Crosland, 2000; DeLeon et al., 2001) and reinforcement histories ( Lattal & Neef, 1996). In addition, we evaluated participant choices for positive and negative reinforcement in both a restricted-choice condition (in which participants could choose positive or negative reinforcement, but not both) and an unrestricted-choice condition (in which the participants could choose one or both reinforcers). If participants chose positive reinforcement over negative reinforcement in the restricted-choice arrangement but chose both reinforcers in the unrestricted-choice arrangement, it would support the hypothesis that the value of the positive reinforcer overrode the value of the negative reinforcer. However, if the participants chose positive reinforcement over negative reinforcement in both the restricted- and unrestricted-choice arrangements, it would support the hypothesis that the positive reinforcer altered the value of the escape contingency.