O'Hora, D., Roche, B., Barnes-Holmes, D., & Smeets, P. M. (2002). Response latencies to multiple derived stimulus relations: Testing two predictions of relational frame theory. The Psychological Record, 52, 51-76.
In Exp 1, 3 college students (aged 21-23 yrs) were exposed to relational pretraining to establish the contextual functions of Same, Opposite, More Than, and Less. Response latencies to probes for derived Same/Opposite relations were significantly lower than those for derived More Than/Less Than relations. Exp 2 exposed 4 Ss (aged 18-21 yrs) to training across each of the 4 relations and used a novel stimulus set to test for reduced response latencies to the derived relations. Response latencies to More-Than/Less-Than probes reduced significantly across the original to the novel stimulus set, whereas latencies to Same/Opposite probes were low across both stimulus sets.