Luciano, C., Gomez Becerra, I. & Rodriguez Valverde, M. (2007).
The role of multiple-exemplar training and naming in establishing derived equivalence in an infant.
Journal of the Experimental Analysis of Behavior, 87, 349-365.
The conditions under which symmetry and equivalence relations develop are still controversial. This paper
reports three experiments that attempt to analyze the impact of multiple-exemplar training (MET) in receptive
symmetry on the emergence of visual–visual equivalence relations with a very young child, Gloria. At the age of
15 months 24 days (15m24d), Gloria was tested for receptive symmetry and naming and showed no evidence of either
repertoire. In the first experiment, MET in immediate and delayed receptive symmetrical responding or listener
behavior (from object–sound to immediate and delayed sound–object selection) proceeded for one month with 10
different objects. This was followed, at 16m25d, by a second test conducted with six new objects. Gloria showed
generalized receptive symmetry with a 3-hr delay; however no evidence of naming with new objects was found.
Experiment 2 began at 17m with the aim of establishing derived visual–visual equivalence relations using a
matching-to-sample format with two comparisons. Visual–visual equivalence responding emerged at 19m, although
Gloria still had not shown evidence of naming. Experiment 3 (22m to 23m25d) used a three-comparison
matching-to-sample procedure to establish visual–visual equivalence. Equivalence responding emerged as in
Experiment 2, and naming emerged by the end of Experiment 3. Results are discussed in terms of the history of
training in bidirectional relations responsible for the emergence of visual–visual equivalence relations and of
their implications for current theories of stimulus equivalence.
Key words: receptive symmetry, listener behavior, equivalence relations, multiple-exemplar training, naming, verbal behavior, Relational Frame Theory, matching to sample, infant