Evaluative conditioning with multiple unconditioned stimuli – Integration at judgment?

Evaluative conditioning (EC), the change in the liking of a conditioned stimulus (CS) due to its pairing with a positive/negative unconditioned stimulus (US), is a central effect in attitude formation. While EC has been widely studied in social psychology for many years, research has only recently begun investigating EC in stimulus-rich situations with multiple simultaneously occurring USs. Initial evidence suggests that conditioned attitudes develop in such situations as if people compute the average valence from the different USs. However, the cognitive processes underlying this averaging are insufficiently understood, especially when they operate in the conditioning process – only at encoding or also at judgment. To test this, we conducted two preregistered experiments where CSs simultaneously appeared with multiple USs and the valence of some of the USs changed after the conditioning procedure. We found that attitudes toward the CSs shifted in line with the changes in US valence, implying integration at judgment. Furthermore, our results confirm that valence integration of multiple USs still follows an averaging pattern, even when some USs change their valence after the initial pairing. Our research reveals key insights into information integration processes in EC, demonstrating that a simple averaging rule predicts conditioned attitudes from complex stimulus arrangements even in situations where affective stimuli change in valence throughout time. Furthermore, this implies that conditioned attitudes are flexibly constructed on the spot by retrieving and averaging the most recent valence information from previously paired attitude objects, showing the adaptivity of conditioned attitudes to new informational input.