An Assimilative Effect of Stimulus Co-Occurrence on Evaluation Despite Contrasting Relational Information.

The co-occurrence of a neutral stimulus with affective stimuli typically causes the neutral stimulus's evaluation to shift toward the affective stimuli's valence. Does that assimilative effect occur even when one knows the co-occurrence is due to an opposition relation between the stimuli (e.g., Batman stops crime )? Previous evidence tentatively supported that possibility, based on results compatible with an assimilative effect obscured by a larger contrast effect of the opposition relation (e.g., people like Batman less than expected, perhaps due to his co-occurrence with crime). We report three experiments ( N = 802) in which participants preferred stimuli that stopped positive events over stimuli that stopped negative events-an assimilative effect of co-occurrence, unobscured by a contrast effect, despite comprehending the opposition relation and its evaluative implications. Our findings suggest that the assimilative effect of co-occurrence is potentially ubiquitous, not limited only to co-occurrence due to relations that suggest valence similarity.