Gil, E., Luciano, C., Ruiz, F. J., & Valdivia-Salas, V. (2012). A Preliminary Demonstration of Transformation of Functions through Hierarchical Relations. International Journal of Psychology and Psychological Therapy, 12, 1, 1-19.
The current study focuses on the experimental analysis of hierarchical responding, and aims at analyzing some of the transformation of functions that take place at different levels of hierarchical categories. Ten university students participated. During Phase 1, four arbitrary stimuli were established as INCLUDES, BELONGS TO, SAME, and DIFFERENT relational cues, respectively. During Phase 2, three four-member equivalence classes were trained and tested (A1-B1-C1-D1; A2-B2-C2-D2; A3-B3-C3-D3). These equivalence classes constituted the bottom level of two hierarchical categories. The middle and top levels of the hierarchical categories were formed during Phase 3. The middle level was established by training hierarchical relations (INCLUDES and BELONGS TO) between novel stimuli X.1 and A1/B1; X. 2 and A2/B2; and Y and A3/B3. The top level was established by training hierarchical relations between X and X.1/X.2, and between Y and Y.1. During Phase 4, X.1 was established as always cold, D2 as always heavy and C3 as always sweet. During Phase 5 (Critical Test), six stimuli from both hierarchical categories (Y, X, C1, X.2, D3, C2) and a non-related stimulus (M) were tested for the transformation of functions. Nine of the ten participants responded correctly to the test. The implications and limitations of these findings, as well as lines for future research, are discussed.