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Abstract In a prior study (Stein et al., 2013), we reported that rats pre‐exposed to delayed rewards made fewer impulsive choices, but consumed more alcohol (12% wt/vol), than rats pre‐exposed to immediate rewards. To understand the mechanisms that produced these findings, we again pre‐exposed rats to either delayed (17.5 s; n = 32) or immediate ( n = 30) rewards. In posttests, delay‐exposed rats made significantly fewer impulsive choices at 15‐ and 30‐s delays to a larger, later food reward than the immediacy‐exposed comparison group. Behavior in an open‐field test provided little evidence of differential stress exposure between groups. Further, consumption of either 12% alcohol or isocaloric sucrose in subsequent tests did not differ between groups. Because Stein et al. introduced alcohol concentration gradually (3–12%), we speculate that their group differences in 12% alcohol consumption were not determined by alcohol's pharmacological effects, but by another variable (e.g., taste) that was preserved as an artifact from lower concentrations. We conclude that pre‐exposure to delayed rewards generalizes beyond the pre‐exposure delay; however, this same experimental variable does not robustly influence alcohol consumption.

Recently, researchers have investigated the effectiveness and efficiency of presenting secondary targets during learning trials for individuals with autism spectrum disorder (ASD). This instructional method may be more efficient than typical methods used with learners with ASD, because learners may acquire secondary targets without additional instruction. This review will discuss the recent literature on providing secondary targets during teaching trials for individuals with ASD, identify common aspects and results among these studies, and identify areas for future research.

Physical activity is crucial for children's health. Fitbit accelerometers were used to measure steps of 6 elementary students during recess. The intervention included reinforcement, self‐monitoring, goal setting, and feedback. Steps taken during the intervention phase ( M = 1,956 steps) were 47% higher than in baseline ( M = 1,326 steps), and the percentage of recess spent in moderate‐to‐vigorous physical activity was higher during intervention ( M = 25%) than in baseline ( M = 4%). These methods successfully increased steps during recess and could be used to increase steps in other settings.

A paired‐stimulus preference assessment was conducted for 6 individuals with developmental disabilities. We selected stimuli that were representatives of 4 categories: chocolate, salty and crunchy, gummy, and fruit and vegetable. For all 6 participants, at least 3 of the 5 most preferred items came from the same category. On subsequent reinforcer assessments, items from the highest ranked preference category, some of which were included in the preference assessments and some of which were not, functioned as reinforcers. These findings suggest that after categories of preferred items are identified, clinicians may be able to identify reinforcers for some individuals without conducting additional assessments.

Discrete‐trial intertemporal choice procedures assess impulsive choice or preference for a smaller, immediate reinforcer over a larger, delayed one. The effect of the delay associated with the larger reinforcer has been the focus of much research. It, however, is not the only delay in the context of discrete‐trial procedures. Often separating each choice trial is an intertrial interval (ITI) that maintains equal trial spacing of the two alternatives. The removal of this ITI has been shown to increase impulsive choice, perhaps because choosing the small alternative results in another choice trial immediately following reinforcer delivery. Impulsive choice has not been affected when the ITI duration is manipulated in conditions that equate the trial presentation rate across the two alternatives. These null results could have been due to floor effects and/or an inadequate range of ITI durations. To address these possibilities, three experiments were conducted to determine how changes in ITI duration affected impulsive choice in rats and pigeons. All three experiments found that preference for the large delayed alternative decreased (i.e., impulsive choice increased) when the ITI was shortened. Satiation was not a likely explanation since preference for the large alternative at the 0‐s delay was not affected by ITI duration. Trial spacing, like other temporal properties of choice situations, is an important variable underlying the occurrence of impulsive choice.

Six typically developing children between 5 and 7 years of age underwent match‐to‐sample training to establish three‐member equivalence classes after first acquiring a unique name for each stimulus. Horne and Lowe's (1996) naming hypothesis predicts that under those circumstances, match‐to‐sample training contingencies may establish intraverbal relations between the unique names, which in turn guide correct responses on a subsequent test for stimulus equivalence. Following training of baseline relations (AB and AC), participants received an equivalence test followed by an intraverbal test. Performance on the two tests co‐varied, such that three participants passed both tests, and three participants failed repeated administrations of both tests, including a modified version of the equivalence test designed to promote intraverbal responding. The participants who failed the equivalence test, however, did so primarily due to poor performance in transitivity trials, but performed accurately in symmetry trials. After training of a third relation (BC), all three participants performed accurately in a symmetry test for the remaining untrained relations (BA, CA, and CB); two of them in the absence of relevant intraverbal repertoires.

Intertemporal choices create a tension between amount maximization, which would favor the larger and later option (LL), and delay minimization, which would promote the smaller and sooner reward (SS). Two common interpretations of intertemporal choice behavior are discussed: looking at LL responses as indicative of self‐control, and using intertemporal choices to assess delay aversion. We argue that both interpretations need to take into account motivational confounds , in order to be warranted by data. In intertemporal choices with prepotent, salient stimuli (e.g., food amounts, typically used with nonhuman primates), LL responses could also be indicative of failed inhibition of a “go for more” impulsive response—the opposite of self‐control. Similarly, intertemporal choices can be used to measure delay aversion only with respect to the subject's baseline motivation to maximize the reinforcer in question, and this baseline is not always assessed in current experimental protocols. This concern is especially crucial in comparing intertemporal choices across different groups or manipulation. We focus in particular on the effects of reward types on intertemporal choices, presenting two experimental studies where the difference in behavior with monetary versus food rewards is the product of different baseline motivation, rather than variations in delay aversion. We conclude discussing the implications of these and other similar recent findings, which are far‐reaching.

Se cuestiona la comparación de la teoría operante con la teoría de campo interconductual. Se examinan las características lógicas de una teoría de campo, los conceptos de teoría y medida molar, así como las características de la categoría de contingencia como noción central de la teoría de campo. Palabras clave : teoría de campo, teoría operante, contingencia, molar, causalidad