Measuring the "transfer of meaning" through members of equivalence classes merged via a class-specific reinforcement procedure.

Seven participants received conditional discrimination training that established the 12 conditional relations A1B1, A2B2, A3B3, A1C1, A2C2, A3C3, D1E1, D2E2, D3E3, D1F1, D2F2, and D3F3. The A stimuli were pictures of faces portraying emotional expressions; the others were arbitrary forms. Correct responses resulted in presentations of class-specific reinforcers, Sr1, Sr2, and Sr3. After training, tests confirmed the formation of ABC and DEF equivalence classes. Further tests then documented the merger of the classes and the emergence of SrB, SrC, SrE, and SrF relations, showing that the class-specific reinforcers were equivalence class members. Finally, participants did Semantic Differential ratings that tested whether the emotional valence of the A stimuli transferred to the arbitrary forms, B and E. The results show that participants' evaluations of the B and E stimuli were similar to evaluations of the A stimuli made by participants of a control group. This finding is considered as a demonstration that class-specific outcomes can mediate class merger phenomena and the transfer of functions through members of merged classes.