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Pavlovian drug discrimination (DD) procedures demonstrate that interoceptive drug stimuli may come to control behavior by informing the status of conditional relationships between stimuli and outcomes. This technique may provide insight into processes that contribute to drug‐seeking, relapse, and other maladaptive behaviors associated with drug abuse. The purpose of the current research was to establish a model of Pavlovian DD in male Japanese quail. A Pavlovian conditioning procedure was used such that 3.0 mg/kg methamphetamine served as a feature positive stimulus for brief periods of visual access to a female quail and approach behavior was measured. After acquisition training, generalization tests were conducted with cocaine, nicotine, and haloperidol under extinction conditions. SCH 23390 was used to investigate the involvement of the dopamine D 1 receptor subtype in the methamphetamine discriminative stimulus. Results showed that cocaine fully substituted for methamphetamine but nicotine only partially substituted for methamphetamine in quail. Haloperidol dose‐dependently decreased approach behavior. Pretreatment with SCH 23390 modestly attenuated the methamphetamine discrimination suggesting that the D 1 receptor subtype may be involved in the discriminative stimulus effects of methamphetamine. The findings are discussed in relation to drug abuse and associated negative health consequences.

Se propone una tarea experimental para la evaluación de la permutación funcional de propiedades de la función selectora (Ribes, 2007). El procedimiento utilizado en este trabajo consistió en poner al participante en una situación en la que debe actuar como ayudante de un detective, identificando el rol que cumplen una serie de personajes en el contexto de una historia policiaca. El participante a lo largo de la tarea debe ir asignando propiedades de tipo convencional (ser inocente, sospechoso o culpable) en función de la información que se va presentando y de las relaciones que pueda establecer entre personajes y situaciones. El análisis trata de dar cuenta de las razones por las cuales el participante asigna o modifica la propiedad o propiedades atribuidas a los personajes. Los resultados parciales evidencian que la tarea propuesta puede constituir un escenario prometedor para el análisis de interacciones de tipo selector. Se concluye que, las mejoras que puedan implementarse al procedimiento y el análisis refinado de los datos pueden constituir un buen punto de partida para dar cuenta de la permutación de propiedades y por ende de la función selectora.

Several studies have examined discounting by pigeons and rats using concurrent‐chains procedures, but the results have been inconsistent. None of these studies, however, has established that discounting functions derived from estimates of indifference points can be obtained with a concurrent‐chains procedure, so their validity remains in doubt. The present study used a concurrent‐chains procedure within sessions combined with an adjusting‐amount procedure across sessions to determine the present, subjective values of food reinforcers to be obtained after a delay. Discounting was well described by the hyperbolic discounting function, suggesting that the concurrent‐chains procedure and the more typical adjusting‐amount procedure are measuring the same process. Consistent with previous studies with rats and pigeons using adjusting‐amount procedures, no significant effect of the amount of the delayed reinforcer on the degree of discounting was observed, suggesting that the amount effect may be unique to humans although consistent with the view that animals' choices are controlled by the relative, rather than the absolute, value of reinforcers.

Recent literature reviews have highlighted the need to better understand the relation between speaker and listener behavior when teaching learners with autism spectrum disorder (ASD). The current paper outlines the practical implications of evaluating the emergence of tact and listener behavior during instruction for the opposite relation, as presented in the preceding article “Evaluating the Efficiency of Listener and Tact Instruction for Children with Autism.” Modifications of those procedures for clinical use as well as future directions for research in this area are presented.

Abstract Eight rats responded on concurrent Variable‐Ratio 20 Extinction schedules for food reinforcement. The assignment of variable‐ratio reinforcement to a left or right lever varied randomly following each reinforcer, and was cued by illumination of a stimulus light above that lever. Postreinforcement preference levels decreased substantially and reliably over time when the lever that just delivered reinforcement was now in extinction; however, if that lever was once again associated with variable ratio, this decrease in same‐lever preference tended to be small, and for some subjects, not in evidence. The changes in preference level to the extinction lever were well described by a modified version of Killeen, Hanson, and Osborne's (1978) induction model. Consistent with this model's attribution of preference change to induction, we attribute preference change in this report to a brief period of reinforcer‐induced arousal that energizes responding to the lever that delivered the last reinforcer. After a few seconds, this induced responding diminishes, and the operant responding that remains comes under the control of the stimulus light cuing the lever providing variable‐ratio reinforcement.

Preference pulses are thought to represent strong, short‐term effects of reinforcers on preference in concurrent schedules. However, the general shape of preference pulses is substantially determined by the distributions of responses‐per‐visit (visit lengths) for the two choice alternatives. In several series of simulations, we varied the means and standard deviations of distributions describing visits to two concurrently available response alternatives, arranged “reinforcers” according to concurrent variable‐interval schedules, and found a range of different preference pulses. Because characteristics of these distributions describe global aspects of behavior, and the simulations assumed no local effects of reinforcement, these preference pulses derive from the visit structure alone. This strongly questions whether preference pulses should continue to be interpreted as representing local effects of reinforcement. We suggest an alternative approach whereby local effects are assessed by subtracting the artifactual part, which derives from visit structure, from the observed preference pulses. This yields “residual” preference pulses. We illustrate this method in application to published data from mixed dependent concurrent schedules, revealing evidence that the delivery of reinforcers had modest lengthening effects on the duration of the current visit, a conclusion that is quantitatively consistent with early research on short‐term effects of reinforcement.

An estimated 30% of Americans meet the criteria for obesity. Effective, low‐cost interventions to increase physical activity are needed to prevent and treat obesity. In this study, 11 healthy adults wore Fitbit accelerometers for 3 weeks. During the initial baseline, subjects earned prize draws for wearing the Fitbit. During intervention, percentile schedules were used to calculate individual prize‐draw criteria. The final week was a return to baseline. Four subjects increased step counts as a result of the intervention. A bout analysis of interresponse times revealed that subjects increased overall step counts by increasing daily minutes active and within‐bout response rates and decreasing pauses between bouts of activity. Strategies to improve effectiveness are suggested, such as modification of reinforcement probability and amount and identification of the function of periods of inactivity. Podcast

Problem behaviors like self‐injury, aggression, or disruption will likely require intervention at some point in the life of a person diagnosed with autism. Behavioral intervention has been proven to be effective for addressing these problems, especially when a functional assessment is conducted. Comprehensive treatment for problem behavior is, however, often fractured across studies, resulting in a dearth of studies that show socially validated improvements in these problem behaviors or illustrate the assessment and treatment process from start to finish. In this article, we describe an effective, comprehensive, and parent‐validated functional assessment and treatment process for the severe problem behaviors of 3 children with autism. After an 8‐ to 14‐week outpatient clinic consultation, no problem behavior was observed at the clinic and in the home. Furthermore, behavior that did not occur during baseline (e.g., functional communication, delay and denial tolerance, and compliance with instructions) occurred with regularity. Video Abstract

Publication bias arises when studies with favorable results are more likely to be reported than are studies with null findings. If this bias occurs in studies with single‐subject experimental designs (SSEDs) on applied behavior‐analytic (ABA) interventions, it could lead to exaggerated estimates of intervention effects. Therefore, we conducted an initial test of bias by comparing effect sizes, measured by percentage of nonoverlapping data (PND), in published SSED studies ( n = 21) and unpublished dissertations ( n = 10) on 1 well‐established intervention for children with autism, pivotal response treatment (PRT). Although published and unpublished studies had similar methodologies, the mean PND in published studies was 22% higher than in unpublished studies, 95% confidence interval (4%, 38%). Even when unpublished studies are included, PRT appeared to be effective (PND M = 62%). Nevertheless, the disparity between published and unpublished studies suggests a need for further assessment of publication bias in the ABA literature.

Nicotine increases the value of some reinforcing stimuli, and this effect may contribute to nicotine's widespread abuse. We aimed to quantify this effect using a behavioral economic analysis. Six Long‐ Evans rats were exposed to a modified observing response procedure. In this procedure, presses to one lever resulted either in food according to a variable‐interval 15 s schedule or extinction; presses to a second, observing lever illuminated stimuli correlated with the schedule in effect on the food/extinction lever (i.e., conditioned reinforcers). The FR requirement on the observing lever increased across sessions. The number of presentations of the conditioned reinforcers was plotted as a function of FR value to generate a demand curve. Nicotine was then administered at a dose of 0.3 mg/kg. All demand curves were fitted to the exponential demand equation and a parameter reflecting reinforcer value was evaluated. Nicotine increased the value of the conditioned reinforcers as measured by this equation; nicotine also increased responding on the food/extinction lever. This analysis demonstrates that nicotine increases the value of conditioned reinforcers under certain conditions. The current procedure allows for a novel method of analyzing demand for conditioned reinforcers.