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Little research has focused on training greater tolerance to delays of rewards in the context of delayed gratification. In delayed gratification, waiting for a delayed outcome necessitates the ability to resist defection for a continuously available smaller, immediate outcome. The present research explored the use of a fading procedure for producing greater waiting in a video‐game based, delayed gratification task. Participants were assigned to conditions in which either the reward magnitude, or the probability of receiving a reward, was a function of time waited and the delay to the maximum reward was gradually increased throughout this training. Waiting increased for all participants but less for those waiting for a greater reward magnitude than a greater reward probability. All participants showed a tendency to wait in a final testing phase, but training with probabilistic outcomes produced a significantly greater likelihood of waiting during testing. The behavioral requirements of delay discounting versus delay gratification are discussed, as well as the benefits of training greater self‐control in a variety of contexts.

Impulsive choice is typically measured by presenting smaller–sooner (SS) versus larger–later (LL) rewards, with biases towards the SS indicating impulsivity. The current study tested rats on different impulsive choice procedures with LL delay manipulations to assess same‐form and alternate‐form test–retest reliability. In the systematic‐GE procedure (Green & Estle, 2003), the LL delay increased after several sessions of training; in the systematic‐ER procedure (Evenden & Ryan, 1996), the delay increased within each session; and in the adjusting‐M procedure (Mazur, 1987), the delay changed after each block of trials within a session based on each rat's choices in the previous block. In addition to measuring choice behavior, we also assessed temporal tracking of the LL delays using the median times of responding during LL trials. The two systematic procedures yielded similar results in both choice and temporal tracking measures following extensive training, whereas the adjusting procedure resulted in relatively more impulsive choices and poorer temporal tracking. Overall, the three procedures produced acceptable same form test–retest reliability over time, but the adjusting procedure did not show significant alternate form test–retest reliability with the other two procedures. The results suggest that systematic procedures may supply better measurements of impulsive choice in rats.

A meta‐analysis of noncontingent reinforcement (NCR) outcomes was conducted using hierarchical linear modeling (a) to document the effect size for decreasing problem behavior, (b) to compare effect sizes for NCR using functional reinforcers and nonfunctional reinforcers, and (c) to document the influence of schedule thinning on effect size. Analyses were conducted with data from 55 studies and 91 participants. Results indicate that NCR was associated with a very strong effect size ( d =–1.58) for reduction of problem behavior, functional reinforcers were slightly more effective than nonfunctional reinforcers, and schedule thinning resulted in minor degradation of effect size. Meta‐analysis of single‐case design data provides a method to quantitatively estimate effect sizes of interventions across participants. Therefore, it allows one to identify important variables that are not otherwise evident in single‐case data, helps to disseminate findings to the broader scientific community, and contributes to the documentation of empirically supported interventions.

Reinforcing an alternative response in the presence of the stimuli governing a target response increases resistance to extinction of target responding, relative to training target responding on its own. Conversely, training alternative and target responses in the presence of different stimuli and combining those stimuli only decreases resistance to extinction of target responding, relative to target responding on its own. The present study assessed how different methods of combining discriminative stimuli influence resistance to extinction of responding in pigeons. As in previous studies, combining stimuli across different keys only decreased resistance to extinction of target responding relative to target responding on its own. In comparison, combining stimuli on the same key initially increased resistance to extinction of target responding, but repeated tests resulted in similar levels of responding as target responding with stimuli combined on separate keys. Moreover, greater overall reinforcement rates produced greater resistance to extinction with both methods of combining stimuli, consistent with behavioral momentum theory. These findings reveal several behavioral processes influence the outcome of combining stimuli—including perceptual processes, discriminative control by contingencies, response competition, and behavioral momentum.

The subjective value of rewards declines the longer rewards are delayed into the future (“delay discounting”). Discounting behavior varies both as a function of an individual's trait and current state. The degree of discounting has repeatedly been associated with relapse following treatment of addiction. Therefore, the effects of acute drug deprivation on discounting processes are potentially of high clinical relevance. In two testing sessions (24 hr of nicotine deprivation vs. normal smoking) 37 heavy smoking participants made choices between immediate and delayed rewards as well as between shorter and longer delayed rewards. We found no evidence for an effect of nicotine deprivation on delay discounting of potentially real monetary rewards in both types of decision tasks. Although choice stochasticity was numerically increased after deprivation, this effect was not significant (p > .1). Participants responded significantly slower after nicotine deprivation. Our study supports previous findings that choice impulsivity as measured using discounting tasks is not affected by nicotine deprivation, at least not if real monetary rewards of lower amounts are at stake.

Humans are reported to discount delayed rewards at lower rates than nonhumans. However, nonhumans are studied in tasks that restrict reinforcement during delays, whereas humans are typically studied in tasks that do not restrict reinforcement during delays. In nonhuman tasks, the opportunity cost of restricted reinforcement during delays may increase delay discounting rates. The present within‐subjects study used online crowdsourcing (Amazon Mechanical Turk, or MTurk) to assess the discounting of hypothetical delayed money (and cigarettes in smokers) under four hypothetical framing conditions differing in the availability of reinforcement during delays. At one extreme, participants were free to leave their computer without returning, and engage in any behavior during reward delays (modeling typical human tasks). At the opposite extreme, participants were required to stay at their computer and engage in little other behavior during reward delays (modeling typical nonhuman tasks). Discounting rates increased as an orderly function of opportunity cost. Results also indicated predominantly hyperbolic discounting, the “magnitude effect,” steeper discounting of cigarettes than money, and positive correlations between discounting rates of these commodities. This is the first study to test the effects of opportunity costs on discounting, and suggests that procedural differences may partially account for observed species differences in discounting.

Two experiments evaluated the effects of the simple‐to‐complex and simultaneous training protocols on the formation of academically relevant equivalence classes. The simple‐to‐complex protocol intersperses derived relations probes with training baseline relations. The simultaneous protocol conducts all training trials and test trials in separate portions of the protocol. In Experiments 1 and 2, participants formed 4 3‐ and 4‐member neuroanatomy classes, respectively. When trained with the simple‐to‐complex protocol, 100% of participants immediately formed the 3‐ or 4‐member classes. When trained with the simultaneous protocol, the 3‐ and 4‐member classes were formed immediately by 75% and 42% of participants, respectively. Thus, the immediate emergence of equivalence classes was an interactive function of training protocol and class size. The remaining participants eventually formed classes after a few cycles of retraining. The incorporation of these training and testing parameters could optimize the use of equivalence‐based instruction for teaching college‐level course content.

Response interruption and redirection (RIRD), a procedure in which demands are delivered contingent on stereotypy, has been shown to reduce vocal and motor stereotypy maintained by automatic reinforcement. However, RIRD can be time consuming and can interrupt ongoing activities and access to reinforcement for appropriate behavior. We attempted to address these limitations by comparing the effectiveness of RIRD using the standard 3‐demand procedure to RIRD using just 1 demand. Results showed that RIRD with 1 demand was effective in reducing stereotypy for all participants, required fewer demands overall, and resulted in shorter implementation time. In addition, 2 participants showed an increase in appropriate play during RIRD. These results suggest RIRD with 1 demand may be an effective and less intrusive procedure for reducing stereotypy.

Domestic dogs are used to aid in the detection of a variety of substances such as narcotics and explosives. Under real‐world detection situations there are many variables that may disrupt the dog's performance. Prior research on behavioral momentum theory suggests that higher rates of reinforcement produce greater resistance to disruption, and that this is heavily influenced by the stimulus‐reinforcer relationship. The present study tests the Pavlovian interpretation of resistance to change using dogs engaged in an odor discrimination task. Dogs were trained on two odor discriminations that alternated every six trials akin to a multiple schedule in which the reinforcement probability for a correct response was always 1. Dogs then received several sessions of either odor Pavlovian conditioning to the S+ of one odor discrimination (Pavlovian group) or explicitly unpaired exposure to the S+ of one odor discrimination (Unpaired group). The remaining odor discrimination pair for each dog always remained an unexposed control. Resistance to disruption was assessed under presession feeding, a food‐odor disruptor condition, and extinction, with baseline sessions intervening between disruption conditions. Equivalent baseline detection rates were observed across experimental groups and odorant pairs. Under disruption conditions, Pavlovian conditioning led to enhanced resistance to disruption of detection performance compared to the unexposed control odor discrimination. Unpaired odor conditioning did not influence resistance to disruption. These results suggest that changes in Pavlovian contingencies are sufficient to influence resistance to change.

Pigeons’ demand and preference for specific and generalized tokens was examined in a token economy. Pigeons could produce and exchange different colored tokens for food, for water, or for food or water. Token production was measured across three phases, which examined: (1) across‐session price increases (typical demand curve method); (2) within‐session price increases (progressive‐ratio, PR, schedule); and (3) concurrent pairwise choices between the token types. Exponential demand curves were fitted to the response data and accounted for over 90% total variance. Demand curve parameter values, P max , O max and α showed that demand was ordered in the following way: food tokens, generalized tokens, water tokens, both in Phase 1 and in Phase 3. This suggests that the preferences were predictable on the basis of elasticity and response output from the demand analysis. P max and O max values failed to consistently predict breakpoints and peak response rates in the PR schedules in Phase 2, however, suggesting limits on a unitary conception of reinforcer efficacy. The patterns of generalized token production and exchange in Phase 3 suggest that the generalized tokens served as substitutes for the specific food and water tokens. Taken together, the present findings demonstrate the utility of behavioral economic concepts in the analysis of generalized reinforcement.