Odors can change preferences for people in photographs: A cross-modal evaluative conditioning study with olfactory USs and visual CSs

Abstract

Evaluative conditioning is a form of Pavlovian conditioning in which the “CR” is a change in preference or liking for the “CS.” It is probably a major cause of development of likes and dislikes in humans. This research introduces a new, cross-modal evaluative conditioning procedure using odors as USs and photographs of people's faces as CSs. When liked, neutral, and disliked odors that were plausibly connected with people were contingently presented with photographs of neutral people, subjects shifted their preference ratings for the people in the photographs presented subsequently without odors in the direction of their preference ratings for the odors. Subjects who developed personality sketches of someone “who looked and smelled this way” showed similar shifts as those who simply studied the odor-picture combinations. Results also suggest that a plausible connection between odors and people may play a role in the success of this conditioning.