(A) The sensory preconditioning experimental design, hypothetical temporal representations, and observed results of Molet, Miguez, Cham, and Miller (2012, Experiment 1). (B) The second-order conditioning experimental design, hypothetical temporal representations, and observed result of Molet, Miguez, Cham, and Miller (2012, Experiment 2). In A and B, extinction of S2 during Phase 3 assessed whether integration occurred during Phase 2 training (i.e., before extinction of S2) or at the time of test (i.e., after extinction of S2). Open rectangles and letters represent conditioned stimuli; black rectangles represent the footshock unconditioned stimulus; each dashed line represents the retrieved activation of a representation. CR = strong conditioned responding; cr = little or no conditioned responding.