Emergence of Simpler Untested Derived Stimulus Relations in Extinction: Implications for Understanding Derived Relational Learning

The purpose of the present research was to clarify further the necessary and sufficient conditions that establish derived stimulus relations. Under more complex conditions (i.e., training involving four, four-member stimulus classes), past research has demonstrated that untested stimulus relations did not emerge when recently trained relational responding was extinguished. The present research examined whether such emergence was more likely under less complex conditions. In experiment 1, untested equivalence relations emerged in extinction using a training structure with three, three-member classes. In experiment 2, untested symmetrical relations emerged in extinction using a training structure with four, four-member classes. The necessary and sufficient conditions that establish derived stimulus classes seem to depend on environmental complexity. Presented are the implications of these findings for conceptualizing derived relational responding as a generalized, or higher-order, response class.