Association for Behavior Analysis International

This symposium will focus on the use of simple discrimination procedures to establish stimulus control and arbitrary classes. These findings have implications for instruction with individuals with minimal repertoires (e.g., disabilities) as they inform on the mechanisms underlying stimulus equivalence and other forms of symbolic behavior. Disruptions to expected stimulus-stimulus relations and their likely causes will be highlighted. The first paper will show effects of simple discrimination training when stimulus functions are reversed (A+ to A-). This reversal learning set repertoire would be required for an individual to form equivalence classes; thus additional training was used to reduce variability on performance of the children with ASD that participated. The second paper will present data on the establishment of functional and equivalence classes via simple discrimination training with young children. Go/no-go procedures with compound stimuli were utilized to test for emergent conditional relations; implications for the role of stimulus function within training and testing will be discussed. Lastly, the effects of verbal responding within a simple discrimination procedure to establish equivalence-equivalence and equivalence class formation will be shown. The adult participants successes, and failures, during testing for emergent relations implicate the role of covert behavioral repertoires within testing conditions.

Children with ASDs show marked variability in communication and discrimination abilities and are often described as behaviorally inflexible on a variety of set-shifting tasks. For example, our recent work has shown substantial variability on tasks that involve stimulus function reversal—a prerequisite skill for matching-to-sample and other symbolic behaviors. We investigated whether management of stimulus control development improves outcomes on reversal learning set (RLS; i.e., "learning to learn"). Eleven children with ASD were trained on simple discrimination between2 stimuli (A+, B-), followed by a series of discrimination reversals (A-, B+). Children who did not show evidence of RLS were given specific training to (a) to attend to and select the S+ and (b) to attend to and reject the S- (s/r training). An additional4 reversals were then conducted. All sessions were recorded and at least 50% were scored for reliability. Thus far, the data replicate previous reports in that some children show development of RLS and others do not. S/r training may reduce variability in reversal acquisition for some of these latter children. Reducing outcome-variability on these types of tasks may increase children's capacity to demonstrate more complex forms of symbolic behavior.

This study investigated whether a simple discrimination procedure would produce functional classes and equivalence classes evaluated using the go/no-go procedure with compound stimuli or the matching-to-sample (MTS) procedure. Eight typically developing children aged between3 and6 years were submitted to training. Response 1 was reinforced only when emitted in the presence of A1, B1, and C1 and Response 2 was reinforced only in the presence of A2, B2, and C2. After training new responses to A1 and A2, functional classes were evaluated with tests that verified if the new responses would be emitted in the presence of B1, B2, C1, and C2. Emergent conditional relations were tested using the go/no-go procedure with compound stimuli in which correct compounds (e.g., A1B1, A2B2, B1C1, B2C2, A1C1, A2C2) and incorrect compounds (e.g., A1B2, A2B1, B1C2, B2C1, A1C2, A2C1) were successively presented. Six children showed functional class formation. Performances indicative of equivalence class formation were demonstrated by2 children with the go/no-go procedure and by3 children only with the MTS procedure. One child did not show equivalence class formation with any of the procedures. Future research should investigate procedural parameters that would reduce between-subject variability found in the present study with children.

Analogical reasoning refers to one’s ability to derive the relation between stimuli, a process necessary for completing Aristotle’s proportional analogies, A:B::C:D. Two 3-member classes made up of abstract figures (A1-B1-C1 and A2-B2-C2) were presented to6 adult participants via computer software. In a simple discrimination procedure, participants were trained to tact AB and BC pairs from within the same class as “same” and pairs from different classes as “different.” Tact and analogy tests with these relations followed. In an "analogy" (equivalence-equivlance) test, selecting the comparison with “same” terms was correct when the sample had “same” terms, vice versa with “different.” This testing sequence was repeated across the compounds consistent with symmetry (BA and CB) and transitivity (AC and CA). Equivalence class formation was tested with the figures presented individually in a conditional discrimination task (e.g., selecting B1 in presence of A1 when told “Select same”). Two of the6 participants passed all presented tasks, supporting the viability of this procedure. The failures of the remaining four participants have implications for the inclusion of verbal responses in simple discrimination procedures. The emergence of equivalence-equivalence following tact training with compound stimuli was shown across all participants, extending the research in the naming operant.