ASSOCIATIVE MEDIATIONAL PROCESSES IN THE ACQUIRED EQUIVALENCE AND DISTINCTIVENESS OF CUES

Three experiments used rats to examine the acquired equivalence or dis tinctiveness of cues occurring when 2 auditory and 2 visual stimuli we re associated with either the same or with different reinforcing outco mes (A(1)+, A(2)+, V-1, and V-2* vs. A(1)+, A(2)*, V-1+, and V2*) Sub sequent single modality discrimination learning (e.g., A(1)+, A(2)-) w as assessed in Experiment 1, whereas in Experiment 2, visual and audit ory discriminations were tested concurrently (i.e., A(1)+,A(2)-, V-1-, V-2). In Experiment 3, auditory and visual discriminations (A(1)+, A( 2)-, V-1-, V-2) were trained and then reversed, using either the same (A(1)-,A(2)+, V-1, V-2-) or different outcomes (A(1)-, A(2)*, V-1+, V-2-) within each stimulus modality. Discriminations were learned more rapidly in these studies when different outcomes were associated with stimuli from the same modality. These results challenge associative m ediational theories of acquired equivalence and distinctiveness.