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Individuals with autism spectrum disorder (ASD) have qualitative impairments in social interaction and often prefer food or tangible reinforcement to social reinforcement. Thus, therapists who work with children with ASD often use food or tangible items as reinforcers to increase appropriate behaviors or decrease problem behaviors. The goal of the present study was to shift children's preferences from a highly preferred tangible item to an initially nonpreferred social reinforcer using an observational conditioning procedure. Participants observed a known peer engage in a simple task and select the social reinforcer that was not preferred by the participant. This procedure resulted in a shift of preference toward the social reinforcer by all participants. Maintenance data showed that although the preference change did not maintain for 1 of the participants, it was quickly reestablished with additional observational trials. Results provide further support for the use of observational procedures to alter preferences.

Lorcaserin is approved by the Food and Drug Administration for treating obesity and is under consideration for treating substance use disorders; it has agonist properties at serotonin (5‐ HT ) 2C receptors and might also have agonist properties at other 5‐ HT receptor subtypes. This study used drug discrimination to investigate the mechanism(s) of action of lorcaserin. Male Sprague–Dawley rats discriminated 0.56 mg/kg i.p. lorcaserin from saline while responding under a fixed‐ratio 5 schedule for food. Lorcaserin (0.178‐1.0 mg/kg) dose‐dependently increased lorcaserin‐lever responding. The 5‐ HT 2C receptor agonist mCPP and the 5‐ HT 2A receptor agonist DOM each occasioned greater than 90% lorcaserin‐lever responding in seven of eight rats. The 5‐ HT 1A receptor agonist 8‐ OH‐DPAT occasioned greater than 90% lorcaserin‐lever responding in four of seven rats. The 5‐ HT 2C receptor selective antagonist SB 242084 attenuated lorcaserin‐lever responding in all eight rats and the 5‐ HT 2A receptor selective antagonist MDL 100907 attenuated lorcaserin‐lever responding in six of seven rats. These results suggest that, in addition to agonist properties at 5‐ HT 2C receptors, lorcaserin also has agonist properties at 5‐ HT 2A and 5‐ HT 1A receptors. Because some drugs with 5‐ HT 2A receptor agonist properties are abused, it is important to fully characterize the behavioral effects of lorcaserin while considering its potential for treating substance use disorders.

This study replicated previous basic research into the dynamics of choice and extended this analysis to children's behavior in a naturalistic setting. Two preschoolers with disabilities were observed interacting with their teachers at baseline and during an experimental analysis involving four pairs of concurrent variable‐interval schedules of adult attention implemented by an experimenter. Each child was exposed to four experimental phases in which the relative reinforcer rates for on‐ and off‐task behavior were 10:1, 1:1, 1:10, and reversed back to 10:1. The 10:1 phase was designed to mimic the same schedules and types of adult attention observed at baseline. We used the generalized matching equation to model steady‐state behavior at the end of the transition phases and to evaluate changes in sensitivity at various points throughout the phases. Choice in transition was evaluated by plotting log behavior ratios by session, cumulated time on‐ and off‐task and cumulated attention for on‐ and off‐task behavior by session, and interreinforcer behavior ratios following different sequences of the first four reinforcer deliveries. The generalized matching equation accounted for a large proportion of variance in steady‐state responding, sensitivity values increased steadily throughout the phases, patterns of choice in transition were similar to those reported in basic research, and interreinforcer preference generally shifted toward the just‐reinforced alternative. These findings are consistent with previous basic research and support the generality of the dynamics of choice to children's on‐ and off‐task behavior reinforced by adult attention.

Researchers typically modify individual functional analysis ( FA ) conditions after results are inconclusive (Hanley, Iwata, & McCord , 2003). Hanley, Jin, Vanselow, and Hanratty (2014) introduced a marked departure from this practice, using an interview‐informed synthesized contingency analysis ( IISCA ). In the test condition, they delivered multiple contingencies simultaneously (e.g., attention and escape) after each occurrence of problem behavior; in the control condition, they delivered those same reinforcers noncontingently and continuously. In the current investigation, we compared the results of the IISCA with a more traditional FA in which we evaluated each putative reinforcer individually. Four of 5 participants displayed destructive behavior that was sensitive to the individual contingencies evaluated in the traditional FA . By contrast, none of the participants showed a response pattern consistent with the assumption of the IISCA . We discuss the implications of these findings on the development of accurate and efficient functional analyses.

Choice behavior was studied under concurrent nonindependent fixed‐ratio fixed‐ratio ( nFR ) schedules of reinforcement, as these schedules result in frequent changeover responses. With these schedules, responses on either operandum count toward the completion of the ratio requirements of both schedules. Five monkeys were subjects, and two pairs of liquid reinforcers were concurrently available: 16% (w/v) and 0% ethanol or 16% and 8% ethanol. For each pair of reinforcers, the nFR sizes were systematically altered across sessions while keeping the schedule size equal for both liquids. Responding varied as a function of reinforcer pair and nFR size. With the 16% and 0% pair, higher response rates were maintained by 16% and were an inverted U‐shape function of nFR size. With 16% and 8%, a greater number of responses initially occurred on the schedule that delivered 8% ethanol. However, as nFR size increased, preference reversed such that responses that delivered 16% ethanol were greater. When the nFR size was subsequently decreased, preference reverted back to 8%. Number of responses emitted per delivery was a dependent variable and, in behavioral economic terms, was the price paid for each liquid delivery. With 16% and 0%, changeover responses initially increased and then decreased as schedule size became larger. In contrast, with the 16% and 8% pair, changeover responses increased directly with schedule size. Responding under nFR schedules is sensitive to differences in reinforcer magnitude and demonstrates that relative reinforcing effects can change as a function of schedule size.

The effectiveness of functional communication training as treatment for problem behavior depends on the extent to which treatment can be extended to typical environments that include unavoidable and unpredictable reinforcement delays. Time‐based progressive delay ( TBPD ) often results in the loss of acquired communication responses and the resurgence of problem behavior, whereas contingency‐based progressive delay ( CBPD ) appears to be effective for increasing tolerance for delayed reinforcement. No direct comparison of TBPD and CBPD has, however, been conducted. We used single‐subject designs to compare the relative efficacy of TBPD and CBPD . Four individuals who engaged in problem behavior (e.g., aggression, vocal and motor disruptions, self‐injury) participated. Results were consistent across all participants, and showed lower rates of problem behavior and collateral responses during CBPD than during TBPD . The generality of CBPD treatment effects, including optimal rates of communication and compliance with demands, was demonstrated across a small but heterogeneous group of participants, reinforcement contingencies, and contexts.

Reinforcers affect behavior. A fundamental assumption has been that reinforcers strengthen the behavior they follow, and that this strengthening may be context‐specific (stimulus control). Less frequently discussed, but just as evident, is the observation that reinforcers have discriminative properties that also guide behavior. We review findings from recent research that approaches choice using nontraditional procedures, with a particular focus on how choice is affected by reinforcers, by time since reinforcers, and by recent sequences of reinforcers. We also discuss how conclusions about these results are impacted by the choice of measurement level and display. Clearly, reinforcers as traditionally considered are conditionally phylogenetically important to animals. However, their effects on behavior may be solely discriminative, and contingent reinforcers may not strengthen behavior. Rather, phylogenetically important stimuli constitute a part of a correlated compound stimulus context consisting of stimuli arising from the organism, from behavior, and from physiologically detected environmental stimuli. Thus, the three‐term contingency may be seen, along with organismic state, as a correlation of stimuli. We suggest that organisms may be seen as natural stimulus‐correlation detectors so that behavioral change affects the overall correlation and directs the organism toward currently appetitive goals and away from potential aversive goals. As a general conclusion, both historical and recent choice research supports the idea that stimulus control, not reinforcer control, may be fundamental.

Many workers in industrialized nations spend their day seated at a desk. Research suggests that accumulated sitting time increases risk for certain diseases (van der Ploeg, Chey, Korda, Banks, & Bauman, 2012). To reduce risk, health researchers recommend frequent standing or walking breaks during the workday. In the current study, we evaluated 3 behavioral interventions to decrease bouts of prolonged sitting among office workers. Information alone was not as effective as a treatment package that consisted of a tactile prompt, feedback, and goal setting.

Overall reinforcer rate appears to affect choice. The mechanism for such an effect is uncertain, but may relate to reinforcer rate changing the discrimination of the relation between stimuli and reinforcers. We assessed whether a quantitative model based on a stimulus‐control approach could be used to account for the effects of overall reinforcer rate on choice under changing time‐based contingencies. On a two‐key concurrent schedule, the likely availability of a reinforcer reversed when a fixed time had elapsed since the last reinforcer, and the overall reinforcer rate was varied across conditions. Changes in the overall reinforcer rate produced a change in response bias, and some indication of a change in discrimination. These changes in bias and discrimination always occurred quickly, usually within the first session of a condition. The stimulus‐control approach provided an excellent account of the data, suggesting that changes in overall reinforcer rate affect choice because they alter the frequency of reinforcers obtained at different times, or in different stimulus contexts, and thus change the discriminated relation between stimuli and reinforcers. These findings support the notion that temporal and spatial discriminations can be understood in terms of discrimination of reinforcers across time and space.

We used an adapted alternating treatments design to compare skill acquisition during discrete‐trial instruction using immediate reinforcement, delayed reinforcement with immediate praise, and delayed reinforcement for 2 children with autism spectrum disorder. Participants acquired the skills taught with immediate reinforcement; however, delayed reinforcement decreased the efficiency and effectiveness of discrete‐trial instruction. We discuss the importance of evaluating the influence of treatment‐integrity errors on skill acquisition during discrete‐trial instruction.