title: The mere exposure effect depends on an odor's initial pleasantness.
abstract: The mere exposure phenomenon refers to improvement of one's attitude toward an a priori neutral stimulus after its repeated exposure. The extent to which such a phenomenon influences evaluation of a priori emotional stimuli remains under-investigated. Here we investigated this question by presenting participants with different odors varying in a priori pleasantness during different sessions spaced over time. Participants were requested to report each odor's pleasantness, intensity, and familiarity. As expected, participants became more familiar with all stimuli after the repetition procedure. However, while neutral and mildly pleasant odors showed an increase in pleasantness ratings, unpleasant and very pleasant odors remained unaffected. Correlational analyses revealed an inverse U-shape between the magnitude of the mere exposure effect and the initial pleasantness of the odor. Consequently, the initial pleasantness of the stimuli appears to modulate the impact of repeated exposures on an individual's attitude. These data underline the limits of mere exposure effect and are discussed in light of the biological relevance of odors for individual survival.
authors.affiliation: Swiss Center for Affective Sciences, University of Geneva , Geneva, Switzerland ; E3 Lab, University of Geneva , Geneva, Switzerland.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Delplanque
authors.affiliation: Swiss Center for Affective Sciences, University of Geneva , Geneva, Switzerland ; E3 Lab, University of Geneva , Geneva, Switzerland.
authors.forename: Géraldine
authors.initials: G
authors.lastname: Coppin
authors.affiliation: E3 Lab, University of Geneva , Geneva, Switzerland.
authors.forename: Laurène
authors.initials: L
authors.lastname: Bloesch
authors.affiliation: Firmenich SA , Geneva, Switzerland.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Cayeux
authors.affiliation: Swiss Center for Affective Sciences, University of Geneva , Geneva, Switzerland ; E3 Lab, University of Geneva , Geneva, Switzerland.
authors.forename: David
authors.initials: D
authors.lastname: Sander
keywords: familiarity; mere exposure; olfaction; pleasantness; preference