Association for Behavior Analysis International

Equivalence classes can be established and expanded in a variety of ways. This symposium presents data on2 distinct methodologies: the use of complex stimuli and programming for the emergence of different relational frames. The first study (Nunes& Maguire) investigated the formation of equivalence classes following simple discrimination training using complex stimuli. The expansion of the subsequent classes was limited only by the number of elements that formed the complex. The second study (F. Persson & Maguire) tested for the formation of stimulus classes following conditional discrimination training using complex samples. Testing revealed the emergence of all stimulus-stimulus relations, including all of the interelement relations. The final paper, (Goff& Maguire) examined the role of contextual stimulus control in equivalence class formation. The initial conditional discriminations trained were relations between words that were antonyms (opposition). The untrained emergent performances were relations based on synonyms (coordination). Thus, it appeared that both relational frames, opposition and coordination, coexisted in the same class, and emerged contingent on context. The results of this symposium are discussed in terms of methodologies for setting the occasion for and the expansion of equivalence classes.

Past research has documented the formation of 3, 4-member stimulus classes when prerequisite training involved only teaching a common name to all members of the potential class. Once this simple discrimination training was complete participants were not only able to match each stimulus that received a common name to one another (visual-visual matching-to-sample) but also to select each member of the class contingent on its spoken (auditory-to-visual matching-to-sample). Thus, simple discrimination training was followed by the untrained emergence of equivalence relations. The current study expanded on this efficiency by using a multielement complex during the naming training (applying a name to a stimulus consisting of 4 physically dissimilar visual elements). Thus, if the complex contained 4-elements then the number of emergent relations that followed a simple discrimination (naming) training was 12. The results of this study documented this outcome and attempted to identify the upper limit of the elements within a complex.

Three typically developed individuals were taught conditional discriminations; matching 2, 4-element complex samples to a specific and invariant color comparison (e.g., red versus green). Training was conducted errorlessly, suing a positional prompt (initially the 4-element complex appear over the S+ stimulus. Contingent on correct responding the complex moved toward the center. Once the participant was able to select the relevant color when both complexes were centered training was complete. Following training testing was conducted to assess all possible stimulus-stimulus relations to evaluate the formation of 2 5-member equivalence classes (the fours individual elements and the related color comparison). Participants demonstrated that conditionally related sample and comparison stimuli had become equivalent generating two sets of 4-member classes. Additionally, participants were able to name the elements despite the fact that no verbal or auditory stimuli were present during the study. These data extend the research on the development of stimulus control following training with complex stimuli. Further, the use of complex stimuli during training expands the already efficient nature of the stimulus equivalence paradigm.

This study examined the role of contextual stimulus control in equivalence class formation. The participant was a 9-year-old boy with a diagnosis of an autism spectrum disorder. All training and testing occurred in a typical public school and the stimuli employed were typical vocabulary words. Two conditional discriminations were initially trained to establish relations based on antonyms: A-B and A-C: A was in opposition to B and A was in opposition to C). Then testing was conducted to determine the emergence of untrained symmetrical and transitive relations. Testing revealed not only the emergence of the symmetrical performances of opposition (B-A and C-A) but also the transitive performances, B-C and C-B, of coordination. Thus, it appeared that both relational frames, opposition, and coordination could be occasioned by context, using the same class of stimuli. The results are discussed in terms of the role of contextual stimulus control and its important in the analysis if complex human behaviors.