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Abstract Behavioral momentum theory suggests that the relation between a discriminative‐stimulus situation and reinforcers obtained in that context (i.e., the Pavlovian stimulus–reinforcer relation) governs persistence of operant behavior. Within the theory, a mass‐like aspect of behavior has been shown to be a power function of predisruption reinforcement rates. Previous investigations of resistance to change in multiple schedules, however, have been restricted to examining response persistence following protracted periods of stability in reinforcer rates within a discriminative situation. Thus, it is unclear how long a stimulus–reinforcer relation must be in effect prior to disruption in order to affect resistance to change. The present experiment examined resistance to change of pigeon's key pecking following baseline conditions where reinforcer rates that were correlated with discriminative‐stimulus situations changed. Across conditions, one multiple‐schedule component arranged either relatively higher rates or lower rates of variable‐interval food delivery, while the other component arranged the opposite rate. These schedules alternated between multiple‐schedule components across blocks of sessions such that reinforcer rates in the components were held constant for 20, 5, 3, 2, or 1 session(s) between alternations. Resistance to extinction was higher in the component that most recently was associated with higher rates of food delivery in all conditions except when schedules alternated daily or every other day. These data suggest that resistance to change in multiple schedules is related to recently experienced reinforcer rates but only when multiple‐schedule components are associated with specific reinforcer rates for several sessions.

This brief review describes research on rumination treatment that emphasizes functional analysis, recent intervention methods (supplemental feeding, fixed‐time stimulus presentation, continuous access to preferred stimulation), clinical implications, and procedural recommendations.

Abstract Restricted and repetitive behavior is a diagnostic characteristic of autism spectrum disorder (ASD). To the extent that the behavior of individuals with ASD can be conceptualized as problems of invariance, our understanding of environmental variables that influence restricted and repetitive behavior may be informed by the basic and applied literature on response variability. The purposes of this paper are (a) to describe how restricted and repetitive behavior can be conceptualized as problems of invariance, (b) to consider the implications of a lack of varied responding for individuals with ASD, (c) to review relevant basic and applied research on response variability, (d) to present methods to address invariant responding for individuals with ASD, and (e) to suggest areas for future research.

Se aclara que en la psicología no se estudian entidades sino campos de relaciones contingentes entre entidades. Los principios o causas aristotélicas constituyen momentos de la actualización de estos campos. Cada momento consiste en un estado del campo de relaciones y el desligamiento funcional, como causa eficiente, se refiere a las transiciones de cambios continuos en los estados durante la actualización. Se examina un ejemplo experimental. Palabras clave : agente causal, causas aristotélicas, cambios, estados.

The present study examined (1) the impact of a brief substance use intervention on delay discounting and indices of substance reward value (RV), and (2) whether baseline values and posttreatment change in these behavioral economic variables predict substance use outcomes. Participants were 97 heavy drinking college students (58.8% female, 41.2% male) who completed a brief motivational intervention (BMI) and then were randomized to one of two conditions: a supplemental behavioral economic intervention that attempted to increase engagement in substance‐free activities associated with delayed rewards (SFAS) or an Education control (EDU). Demand intensity, and Omax, decreased and elasticity significantly increased after treatment, but there was no effect for condition. Both baseline values and change in RV, but not discounting, predicted substance use outcomes at 6‐month follow‐up. Students with high RV who used marijuana were more likely to reduce their use after the SFAS intervention. These results suggest that brief interventions may reduce substance reward value, and that changes in reward value are associated with subsequent drinking and drug use reductions. High RV marijuana users may benefit from intervention elements that enhance future time orientation and substance‐free activity participation.

Sunstein argues for an exception to John Stuart Mill's principle that government should never interfere with a person's freedom of choice for the person's “own good” unless that choice will harm others. If a particular government‐imposed contingency is soft rather than harsh, if it acts on means rather than ends, if all alternatives remain available, and if the person herself would ultimately have chosen the alternative now made less costly, more salient, or easier to obtain, then that governmental control is a nudge, and for Sunstein nudges are permissible. Sunstein couches his recommendations in a dichotomy between two internal processes (System 1 and System 2) corresponding to areas of the brain governing fast, intuitive thinking and slow, analytic thinking. Nudges nudge people in a direction governed by System 2. This internalization and dichotomization of what is essentially a continuum between long‐term, more abstract contingencies and short‐term, less abstract contingencies may divert the reader's attention away from the contingencies themselves. Such diversion, if it were taken seriously, would hinder the development of effective and at the same time gentle nudges. Fortunately, none of the nudges proposed by Sunstein depend on the “psychology” represented by System 1 and System 2. The book remains focused on choice architecture. The behavioristic reader can easily translate from neurocognitive to behavioral terms and so see nudges as means of bringing behavior under the control of wide and abstract reinforcer contingencies.

This study investigated the effects of 2 interdependent group contingencies (individual vs. cumulative classroom goal setting) on the number of pedometer‐recorded steps taken per day. Thirty third‐grade students in 2 classrooms participated. An ABACX design was conducted in which the X phase referred to a replication of the most successful phase (i.e., B or C). Results indicated that individual goal setting, rather than cumulative classroom goal setting, was more effective in increasing the number of steps taken per day on average. Results suggest that individual feedback may be an important factor in attaining desired results.

To investigate the coding strategies that pigeons may use in a temporal discrimination tasks, pigeons were trained on a matching‐to‐sample procedure with three sample durations (2s, 6s and 18s) and two comparisons (red and green hues). One comparison was correct following 2‐s samples and the other was correct following both 6‐s and 18‐s samples. Tests were then run to contrast the predictions of two hypotheses concerning the pigeons’ coding strategies, the multiple‐coding and the single‐code/default. According to the multiple‐coding hypothesis, three response rules are acquired, one for each sample. According to the single‐code/default hypothesis, only two response rules are acquired, one for the 2‐s sample and a “default” rule for any other duration. In retention interval tests, pigeons preferred the “default” key, a result predicted by the single‐code/default hypothesis. In no‐sample tests, pigeons preferred the key associated with the 2‐s sample, a result predicted by multiple‐coding. Finally, in generalization tests, when the sample duration equaled 3.5s, the geometric mean of 2s and 6s, pigeons preferred the key associated with the 6‐s and 18‐s samples, a result predicted by the single‐code/default hypothesis. The pattern of results suggests the need for models that take into account multiple sources of stimulus control.

Relational frame theory (RFT) conceptualizes analogy as the establishment of a relation of coordination among common types of relations. This study provided an initial RFT analysis of analogy aptness. Twenty participants initially learned to respond to the structure of analogical tests after which they were trained on two separate relational networks, each consisting of three equivalence classes (Network: 1 F1‐G1‐H1, F2‐G2‐H2, F3‐G3‐H3; Network 2: M1‐N1‐O1, M2‐N2‐O2, M3‐N3‐O3). The node stimuli always appeared with color spots on their backgrounds (F1 and M1: yellow; F2 and M2: red; F3 and M3: blue). In the critical test, participants had to select the more correct response from two options: relating combinatorial relations of coordination with the same color in the node stimuli (e.g., relating G1H1 to N1O1) versus relating combinatorial relations with different colors in the node stimuli (e.g., relating G1H1 to N2O2). The colors of the node stimuli did not appear on the critical test. Ninety percent of participants selected the analogies with common color properties as the more correct ones. Practical implications of these findings are discussed.

Contextual control has been described as (1) a five‐term contingency, in which the contextual stimulus exerts conditional control over conditional discriminations, and (2) allowing one stimulus to be a member of different equivalence classes without merging them into one. Matching‐to‐sample is the most commonly employed procedure to produce and study contextual control. The present study evaluated whether the go/no‐go procedure with compound stimuli produces equivalence classes that share stimuli. This procedure does not allow the identification of specific stimulus functions (e.g., contextual, conditional, or discriminative functions). If equivalence classes were established with this procedure, then only the latter part of the contextual control definition (2) would be met. Six undergraduate students participated in the present study. In the training phases, responses to AC, BD, and XY compounds with stimuli from the same classes were reinforced, and responses to AC, BD, and XY compounds with stimuli from different classes were not. In addition, responses to X1A1B1, X1A2B2, X2A1B2, and X2A2B1 compounds were reinforced and responses to the other combinations were not. During the tests, the participants had to respond to new combinations of stimuli compounds YCD to indicate the formation of four equivalence classes that share stimuli: X1A1B1Y1C1D1, X1A2B2Y1C2D2, X2A1B2Y2C1D2, and X2A2B1Y2C2D1. Four of the six participants showed the establishment of these classes. These results indicate that establishing contextual stimulus functions is unnecessary to produce equivalence classes that share stimuli. Therefore, these results are inconsistent with the first part of the definition of contextual control.