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The current study compared the differential effects of choice and no‐choice reinforcement conditions on skill acquisition. In addition, we assessed preference for choice‐making opportunities with 3 children with autism, using a modified concurrent‐chains procedure. We replicated the experiment with 2 participants. The results indicated that choice‐making opportunities increased treatment efficacy for 2 of the 3 participants, and all 3 participants demonstrated a preference for choice‐making opportunities.

Using procedures similar to those of Tiger, Hanley, and Heal (2006), we compared two multiple‐schedule variations (S+/S– and S+ only) to treat high‐rate requests for edible items in the Picture Exchange Communication System ( PECS ). Two individuals with autism participated, after they showed persistent requests for edible items after PECS training. Stimulus control was achieved only with the multiple schedule that involved presentation of a discriminative stimulus during reinforcement components and its removal during extinction components (S+ only). Discriminated requests were maintained for the 1 participant who experienced schedule thinning.

Children often make impulsive choices, and previous research has shown that access to activities during the delay may enhance self‐control (e.g., Newquist, Dozier, & Neidert, 2012). The purpose of the current study was to extend the results of Newquist et al. (2012) by comparing the effects of access to low‐preference, moderate‐preference, and high‐preference toys during delays. Results showed that (a) all toys increased self‐control for 2 participants when toys were available for all choice options and (b) high‐preference toys (and sometimes moderate‐preference toys) increased self‐control for 3 participants when the toys were available only for large delayed choices.

We evaluated the usefulness of 2 assessments to guide treatment selection for individuals whose prior functional analysis indicated that automatic reinforcement maintained their problem behavior. In the 1st assessment, we compared levels of problem behavior during a noncontingent play condition and an alone or ignore condition. In the 2nd, we assessed participants’ relative preferences for automatic reinforcement and social reinforcers in a concurrent‐operants arrangement. We used the results of these 2 assessments to assign 5 participants to a treatment based on noncontingent access to social reinforcers or to a treatment based on differential access to social reinforcers. We conducted monthly probes with the participants over 10 to 12 months to evaluate the effects of the treatment procedures. All participants showed reductions in problem behavior over this period.

Studies of behavioral momentum reveal that reinforcing an alternative response in the presence of a target response reduces the rate of target responding but increases its persistence, relative to training the target response on its own. Because of the parallels between these studies and differential‐reinforcement techniques to reduce problem behavior in clinical settings, alternative techniques to reduce problem behavior without enhancing its persistence are being explored. One potential solution is to train an alternative response in a separate stimulus context from problem behavior before combining the alternative stimulus with the target stimulus. The present study assessed how differences in reinforcement contingencies and rate for alternative responding influenced resistance to extinction of target responding when combining alternative and target stimuli in pigeons. Across three experiments, alternative stimuli signaling a response–reinforcer dependency and greater reinforcer rates more effectively decreased the persistence of target responding when combining alternative and target stimuli within the same extinction tests, but not when compared across separate extinction tests. Overall, these findings reveal that differences in competition between alternative and target responding produced by contingencies of alternative reinforcement could influence the effectiveness of treating problem behavior through combining stimulus contexts.

We modified functional analysis procedures to include a condition in which we reinforced problem behavior by complying with a child's mands. After identifying compliance with mands as a reinforcer, we evaluated the efficacy of a token system with a response‐cost contingency and incorporated discriminative stimuli to signal when mands would be reinforced. The token system with response cost effectively reduced problem behavior. Similar procedures may be beneficial when continuous adult compliance is not possible, when adults want to control when they will comply with the child's mands, or to build a child's tolerance for adult‐directed situations.

The behavioral‐momentum model of resurgence predicts reinforcer rates within a resurgence preparation should have three effects on target behavior. First, higher reinforcer rates in baseline (Phase 1) produce more persistent target behavior during extinction plus alternative reinforcement. Second, higher rate alternative reinforcement during Phase 2 generates greater disruption of target responding during extinction. Finally, higher rates of either reinforcement source should produce greater responding when alternative reinforcement is suspended in Phase 3. Recent empirical reports have produced mixed results in terms of these predictions. Thus, the present experiment further examined reinforcer‐rate effects on persistence and resurgence. Rats pressed target levers for high‐rate or low‐rate variable‐interval food during Phase 1. In Phase 2, target‐lever pressing was extinguished, an alternative nose‐poke became available, and nose‐poking produced either high‐rate variable‐interval, low‐rate variable‐interval, or no (an extinction control) alternative reinforcement. Alternative reinforcement was suspended in Phase 3. For groups that received no alternative reinforcement, target‐lever pressing was less persistent following high‐rate than low‐rate Phase‐1 reinforcement. Target behavior was more persistent with low‐rate alternative reinforcement than with high‐rate alternative reinforcement or extinction alone. Finally, no differences in Phase‐3 responding were observed for groups that received either high‐rate or low‐rate alternative reinforcement, and resurgence occurred only following high‐rate alternative reinforcement. These findings are inconsistent with the momentum‐based model of resurgence. We conclude this model mischaracterizes the effects of reinforcer rates on persistence and resurgence of operant behavior.

The Odor Span Task is an incrementing non‐matching‐to‐sample procedure that permits the study of behavior under the control of multiple stimuli. Rats are exposed to a series of odor stimuli and selection of new stimuli is reinforced. Successful performance thus requires remembering which stimuli have previously been presented during a given session. This procedure has been frequently used in neurobiological studies as a rodent model of working memory; however, only a few studies have examined the effects of drugs on performance in this task. The present experiments explored the behavioral pharmacology of a modified version of the Odor Span Task by determining the effects of stimulant drugs methylphenidate and methamphetamine, NMDA antagonist ketamine, and positive GABA A modulator flunitrazepam. All four drugs produced dose‐dependent impairment of performances on the Odor Span Task, but for methylphenidate and methamphetamine, these occurred only at doses that had similar effects on performance of a simple odor discrimination. Generally, these disruptions were based on omission of responding at the effective doses. The effects of ketamine and flunitrazepam were more selective in some rats. That is, some rats tested under flunitrazepam and ketamine showed decreases in accuracy on the Odor Span Task at doses that did not affect simple discrimination performance. These selective effects indicate disruption of within‐session stimulus control. Overall, these findings support the potential of the Odor Span Task as a baseline for the behavioral pharmacological analysis of remembering.

McDowell ’s evolutionary theory of behavior dynamics (McDowell, 2004) instantiates populations of behaviors (abstractly represented by integers) that evolve under the selection pressure of the environment in the form of positive reinforcement. Each generation gives rise to the next via low‐level Darwinian processes of selection, recombination, and mutation. The emergent patterns can be analyzed and compared to those produced by biological organisms. The purpose of this project was to explore the effects of high mutation rates on behavioral variability in environments that arranged different reinforcer rates and magnitudes. Behavioral variability increased with the rate of mutation. High reinforcer rates and magnitudes reduced these effects; low reinforcer rates and magnitudes augmented them. These results are in agreement with live‐organism research on behavioral variability. Various combinations of mutation rates, reinforcer rates, and reinforcer magnitudes produced similar high‐level outcomes (equifinality). These findings suggest that the independent variables that describe an experimental condition interact; that is, they do not influence behavior independently. These conclusions have implications for the interpretation of high levels of variability, mathematical undermatching, and the matching theory. The last part of the discussion centers on a potential biological counterpart for the rate of mutation, namely spontaneous fluctuations in the brain's default mode network.

Social validity of behavioral interventions typically is assessed with indirect methods or by determining preferences of the individuals who receive treatment, and direct observation of caregiver preference rarely is described. In this study, preferences of 5 caregivers were determined via a concurrent‐chains procedure. Caregivers were neurotypical, and children had been diagnosed with developmental disabilities and engaged in problem behavior maintained by positive reinforcement. Caregivers were taught to implement noncontingent reinforcement ( NCR ), differential reinforcement of alternative behavior ( DRA ), and differential reinforcement of other behavior ( DRO ), and the caregivers selected interventions to implement during sessions with the child after they had demonstrated proficiency in implementing the interventions. Three caregivers preferred DRA , 1 caregiver preferred differential reinforcement procedures, and 1 caregiver did not exhibit a preference. Direct observation of implementation in concurrent‐chains procedures may allow the identification of interventions that are implemented with sufficient integrity and preferred by caregivers.