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Journal of the Experimental Analysis of Behavior


Stimulus equivalence, Stimulus prompt, Time-delay, Equivalence-based instruction, Conditional discrimination, College students, Autism


Stimulus equivalence is defined as the ability to relate stimuli in novel ways after training in which not all of the stimuli had been directly linked to one another. Sidman (2000) suggested all elements of conditional discrimination training contingencies that result in equivalence potentially become class members. Research has demonstrated the inclusion of samples, comparisons, responses, and reinforcers in equivalence classes. Given the evidence that all elements of a conditional discrimination become part of the class, the purpose of this study was to determine if class-specific prompts would also enter into their relevant equivalence classes. Experiment 1 investigated the inclusion of prompts in an equivalence class using abstract stimuli with neurotypical students enrolled in higher education courses. Experiment 2 systematically replicated Experiment 1 using meaningful stimuli and individuals diagnosed with autism spectrum disorder. The results of both experiments demonstrated that class-specific prompts became part of equivalence classes with the other positive elements of the contingency. The results are discussed in terms of class expansion and the potential impact on equivalence-based instruction.




This is the peer reviewed version of the following article: Palmer, S.K., Maguire, R.W., Lionello‐DeNolf, K.M. and Braga‐Kenyon, P. (2021), Expansion of Sidman's theory: The inclusion of prompt stimuli in equivalence classes. Jrnl Exper Analysis Behavior, 115: 255-271, which has been published in final form at This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.


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