Representational Blending in Human Conditional Learning: Implications for Associative Theory

Abstract

In two experiments, participants were presented with pictures of different foods (A, B, C, D, X,) and learned which combinations resulted in an allergic reaction in a fictitious patient, MrX. In Problem 1, when Aor B (but not Cor D) was combined with food Xan allergic reaction occurred, and when C or D(but not A or B) was combined with Y an allergic reaction occurred. In Experiment 1, participants also received Problem 2 in which A, B, C, and Dinteracted with foods V and Weither in the same way as X and Y, respectively, or in a different way. Participants performed more proficiently in the former than in the latter condition. In Experiment 2, after training on Problem 1, participants judged whether or not novel combinations of foods (e.g., AB, CD, AD, CB) would cause an allergic reaction in MrX. They were no more likely to indicate that ABor CD would cause an allergic reaction than AD or CB, but made their judgements more rapidly and with greater confidence on AB and CDtrials than on ADand CB trials. These results (1) indicate that shared representations come to be addressed by the components of similar compounds (e.g., AX and BX) that have predicted the same outcome (an allergic reaction), and (2) are inconsistent with standard, associative theories of learning, but (3) are consistent with findings from nonhuman animals and with a connectionist interpretation of these findings.