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Resurgence refers to the recurrence of an extinguished target behavior following subsequent suspension of alternative reinforcement. Delivery of reinforcers during extinction of alternative behavior has been shown to mitigate resurgence. The present experiment aimed to determine whether delivering stimuli associated with reinforcers during resurgence testing similarly mitigates resurgence. Three groups of rats pressed target levers for food according to variable‐interval 15‐s schedules during Phase 1. In Phase 2, lever pressing was extinguished, and an alternative nose‐poke response produced alternative reinforcement according to a variable‐interval 15‐s schedule. Food reinforcement was always associated with illumination of the food aperture and an audible click from the pellet dispenser during Phases 1 and 2. Phase 3 treatments differed between groups. For one group, nose poking continued to produce food and food‐correlated stimuli. Both of these consequences were suspended for a second group. Finally, nose poking produced food‐correlated stimuli but not food for a third group. Target‐lever pressing resurged in the group that received no consequences and in the group that received only food‐correlated stimuli for nose poking. Resurgence, however, was smaller for the group that received food‐correlated stimuli than for the group that received no consequences for nose poking. Target‐lever pressing did not increase between phases in the group that continued to receive food and associated stimuli. Thus, delivery of stimuli associated with food reinforcement after suspension of food reduced but did not eliminate resurgence of extinguished lever pressing. These findings contribute to potential methodologies for preventing relapse of extinguished problem behavior in clinical settings.

Pigeons made repeated choices between earning and exchanging reinforcer‐specific tokens (green tokens exchangeable for food, red tokens exchangeable for water) and reinforcer‐general tokens (white tokens exchangeable for food or water) in a closed token economy. Food and green food tokens could be earned on one panel; water and red water tokens could be earned on a second panel; white generalized tokens could be earned on either panel. Responses on one key produced tokens according to a fixed‐ratio schedule, whereas responses on a second key produced exchange periods, during which all previously earned tokens could be exchanged for the appropriate commodity. Most conditions were conducted in a closed economy, and pigeons distributed their token allocation in ways that permitted food and water consumption. When the price of all tokens was equal and low, most pigeons preferred the generalized tokens. When token‐production prices were manipulated, pigeons reduced production of the tokens that increased in price while increasing production of the generalized tokens that remained at a fixed price. The latter is consistent with a substitution effect: Generalized tokens increased and were exchanged for the more expensive reinforcer. When food and water were made freely available outside the session, token production and exchange was sharply reduced but was not eliminated, even in conditions when it no longer produced tokens. The results join with other recent data in showing sustained generalized functions of token reinforcers, and demonstrate the utility of token‐economic methods for assessing demand for and substitution among multiple commodities in a laboratory context.

Symmetry refers to the observation that subjects will derive B‐A (e.g., in the presence of B, select A) after being trained on A‐B (e.g., in the presence of A, select B). Whereas symmetry is readily shown in humans, it has been difficult to demonstrate in nonhuman animals. This difficulty, at least in pigeons, may result from responding to specific stimulus properties that change when sample and comparison stimuli switch roles between training and testing. In three experiments with humans, we investigated to what extent human responding is influenced by the temporal location of stimuli using a successive matching‐to‐sample procedure. Our results indicate that temporal location does not spontaneously control responding in humans, although it does in pigeons. Therefore, the number of functional stimuli that humans respond to in this procedure may be half of the number of functional stimuli that the pigeons respond to. In a fourth experiment, we tested this assumption by doubling the number of functional stimuli controlling responding in human participants in an attempt to make the test more comparable to symmetry tests with pigeons. Here, we found that humans responded according to indirect class formation in the same manner as pigeons do. In sum, our results indicate that functional symmetry is readily observed in humans, even in cases where the temporal features of the stimuli prevent functional symmetry in pigeons. We argue that this difference in behavior between the two species does not necessarily reflect a difference in capacity to show functional symmetry between both species, but could also reflect a difference in the functional stimuli each species responds to.

Sober analyzes two paradigms of parsimony that have been used successfully in science. These are associated with two interpretations of probability: Bayesian and frequentist. Sober applies these paradigms to problems in biology, psychology, and philosophy. In the chapter on psychology, he argues that objective data consisting of environmental input and two or more concurrent responses could be used to refute empirically the radical behaviorist thesis that probability of learned responses can be accounted for solely on the basis of environmental variables. Sober believes that such data are readily available and offers a thought experiment to illustrate his point. Behavior analysts, however, would want actual experimental data, undoubtedly with animals, before accepting any such refutation. Nonetheless, Sober's philosophical point about the type of experiment that would be capable of refuting this thesis is valid. The behavior analytic program, however, does not depend upon the truth of this thesis.

We taught three children diagnosed with autism spectrum disorder to request help using an interrupted chain procedure during which we manipulated task materials such that the child was either incapable or capable of independently completing a link of a behavior chain. We initially observed undesirable generalization of requests for help during capable trials when teaching was introduced during incapable trials for two participants and to a lesser extent for the third participant. However, with repeated exposure to differential prompting and reinforcement across incapable and capable trials, differential responding was observed across EO‐present and EO‐absent trials for all three participants during both teaching sets and one generalization set that was never exposed to teaching procedures. These findings suggest that it is important to consider the antecedent conditions under which the response should occur when teaching children to request help.

Children with autism spectrum disorder (ASD) often have difficulty inferring the private events of others, including private verbal behavior (e.g., thoughts), private emotional responses, and private establishing operations, often referred to as “perspective taking” by the general psychology community. Children with ASD also have difficulty responding to disguised mands. Skinner's description of the “disguised mand” is verbal behavior wherein the speaker's mand directly describes neither its reinforcer nor the corresponding establishing operations. Appropriate responding to disguised mands is required for successful social interaction, making it a social skill worth teaching to children with ASD. We used a nonconcurrent multiple baseline across participants design to investigate the effects of a multiple exemplar training package consisting of rules, role play, and feedback for teaching three boys with ASD to respond to disguised mands. The intervention was effective and generalization to novel disguised mands and people was observed.

The present study evaluated the feasibility of the PEAK Relational Training System's Generalization Module (Dixon, 2014b) to teach and establish generalization of autoclitic mands, distorted tacts, and creative path finding in three children diagnosed with autism spectrum disorder. Using a multiple‐baseline design across behaviors, each participant was provided with differential reinforcement and a least‐to‐most prompting hierarchy for correct responses to a subset of stimuli, and responses to other similar stimulus sets were probed for emergent generalization. Following training, each participant successfully acquired the directly trained behaviors and demonstrated generalization to the nonreinforced test exemplars. These data support the utility of Skinner's (1957) analysis to teach complex forms of verbal operants, and suggest that a manualized curriculum such as PEAK may have utility for promoting skill development and generalization for front line staff and caregivers of children with autism.

The present study was designed to teach conversational speech using text‐message prompts to children with autism spectrum disorder (ASD) in home play settings with siblings and peers. A multiple baseline design across children was used. Children learned conversational speech through the text‐message prompts, and the behavior generalized across peers and settings. Maintenance of treatment gains was seen at 1‐month follow‐up probes. Social validity measures indicated that parents of typically developing children viewed the participants' conversational speech as much improved after the intervention. Results are discussed in terms of the efficacy of text‐message prompts as a promising way to improve conversational speech for children with ASD.

We taught three children with visual impairments to make tactile discriminations of the braille alphabet within a matching‐to‐sample format. That is, we presented participants with a braille character as a sample stimulus, and they selected the matching stimulus from a three‐comparison array. In order to minimize participant errors, we initially arranged braille characters into training sets in which there was a maximum difference in the number of dots comprising the target and nontarget comparison stimuli. As participants mastered these discriminations, we increased the similarity between target and nontarget comparisons (i.e., an approximation of stimulus fading). All three participants’ accuracy systematically increased following the introduction of this identity‐matching procedure.

The study evaluated the efficacy of observational learning using the rival‐model technique in teaching three children with autism to state metaphorical statements about emotions when provided a picture, as well as to intraverbally state an appropriate emotion when provided a scenario and corresponding metaphorical emotion. The results provide a preliminary evaluation of how an observational teaching strategy may be effective in teaching children with autism to correctly tact emotions when given metaphors.