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Prior research has shown that nonhumans show an extreme preference for variable‐ over fixed‐delays to reinforcement. This well‐established preference for variability occurs because a reinforcer's strength or “value” decreases according to a curvilinear function as its delay increases. The purpose of the present experiments was to investigate whether this preference for variability occurs with human participants making hypothetical choices. In three experiments, participants recruited from Amazon Mechanical Turk made choices between variable and fixed monetary rewards. In a variable‐delay procedure, participants repeatedly chose between a reward delivered either immediately or after a delay (with equal probability) and a reward after a fixed delay (Experiments 1 and 2). In a double‐reward procedure, participants made choices between an alternative consisting of two rewards, one delivered immediately and one after a delay, and a second alternative consisting of a single reward delivered after a delay (Experiments 1 and 3). Finally, all participants completed a standard delay‐discounting task. Although we observed both curvilinear discounting and magnitude effects in the standard discounting task, we found no consistent evidence of a preference for variability—as predicted by two prominent models of curvilinear discounting (i.e., a simple hyperbola and a hyperboloid)—in our variable‐delay and double‐reward procedures. This failure to observe a preference for variability may be attributed to the hypothetical, rule‐governed nature of choices in the present study. In such contexts, participants may adopt relatively simple strategies for making more complex choices.

This study aimed to teach individuals with autism spectrum disorder (ASD) and limited vocal speech to emit target vocalizations while using a speech‐generating device (SGD). Of the 4 participants, 3 began emitting vocal word approximations with SGD responses after vocal instructional methods (delays, differential reinforcement, prompting) were introduced. Two participants met mastery criterion with a reinforcer delay and differential reinforcement, and 1 met criterion after fading an echoic model and prompt delay. For these participants, vocalizations initiated before speech outputs were shown to increase, and vocalizations generalized to a context in which the SGD was absent. The 4th participant showed high vocalization rates only when prompted. The results suggest that adding vocal instruction to an SGD‐based intervention can increase vocalizations emitted along with SGD responses for some individuals with ASD.

Noncontingent reinforcement ( NCR ) and response blocking are 2 common interventions for problem behavior maintained by automatic reinforcement. We implemented NCR and blocking with 1 boy and found this combined intervention to be effective at decreasing high rates of automatically reinforced pica. With another child, we compared the effects of blocking alone to the combined intervention. With the third child, we compared NCR alone and blocking alone to the combined intervention. Results showed that the combined intervention was effective at reducing automatically reinforced problem behavior while moderate to high levels of item engagement maintained. When evaluated individually, neither NCR nor blocking was sufficient to reduce problem behavior to clinically significant levels.

Research has identified a variety of effective approaches for responding to errors during discrete‐trial training. In one commonly used method, the therapist delivers a prompt contingent on the occurrence of an incorrect response and then re‐presents the trial so that the learner has an opportunity to perform the correct response independently. Some authors recommend inserting trials with previously mastered targets between the prompted response and opportunities to respond independently, but no studies have directly examined the benefits of this approach. In this study, we manipulated the placement of trials with mastered targets during discrete‐trial training to compare the effectiveness of error correction with and without this recommended insertion procedure. Four children with autism participated, and each was taught 18 targets across 3 target sets. Results indicated that embedding trials with mastered targets into error correction may not confer benefits for most children and that doing so may lead to less efficient instruction.

We reanalyzed published studies that reported functional analyses conducted in the presence and absence of medication. In Analysis 1, we assessed the overall effect of psychotropic medication on problem behavior. Medication had a reductive effect in 29 of the 37 sets of functional analyses reviewed. The magnitude of the effect was associated with the baseline level of responding according to a rate‐dependency function. Analysis 2 examined medication‐induced changes in behavior function. The introduction of medication was followed by the emergence of a new function (1), a change in functions (1), the subtraction of one function in multiply controlled problem behavior (2), and near‐zero levels of responding (6). Thus, in 4 of 37 cases reviewed, medication may have induced function‐specific changes in problem behavior. We discuss the implications of these findings for a closer collaboration between behavior analysts and prescribing professionals in the treatment of problem behavior.

Dymond, Clarke, Dunlap, and Steiner's (2000) analysis of international publication trends in the Journal of Applied Behavior Analysis ( JABA ) from 1970 to 1999 revealed low numbers of publications from outside North America, leading the authors to express concern about the lack of international involvement in applied behavior analysis. They suggested that a future review would be necessary to evaluate any changes in international authorship in the journal. As a follow‐up, we analyzed non‐U.S. publication trends in the most recent 15 years of JABA and found similar results. We discuss potential reasons for the relative paucity of international authors and suggest potential strategies for increasing non‐U.S. contributions to the advancement of behavior analysis.