Evidence for the application of rules in Pavlovian electrodermal conditioning with humans

Two Pavlovian SCR conditioning experiments investigated interference effect s in sequential training of positive and negative patterning discrimination s in humans. In Experiment 1, positive patterning (A -, B -, AB +) was trai ned in Phase 1, immediately followed by a negative patterning schedule (C , D +, CD -). We predicted that human participants would learn a specific n umerosity rule in positive patterning, which interferes with the subsequent negative patterning schedule. In Experiment 2, negative patterning (C +, D +, CD -) was trained in Phase 1, followed by a positive patterning schedul e (A -. B -, AB +) in Phase 2. Because human participants would learn an ab stract 'separate-versus-together'- or 'opposite'-rule to solve the negative patterning discrimination in Phase 1, there should be less interference in positive patterning in Phase 2 where the separate/together-rule could be a pplied, too. In both experiments, the initial patterning discriminations we re acquired successfully. In Experiment 1, human participants totally faile d to solve the Phase 2 discrimination, while in Experiment 2 appropriate re sponse differentiation developed in Phase 2. Thus, without pre-experience h uman participants seem to utilize a specific numerosity-rule in positive pa tterning and a separate/together-rule in negative patterning. (C) 2001 Else vier Science B.V. All rights reserved.