The mere exposure effect depends on an odor's initial pleasantness

Area of Science:

• Psychology
• Sensory Science
• Olfactory Perception

Background:

• The mere exposure phenomenon describes how repeated exposure to a stimulus enhances positive attitudes.
• Its influence on pre-existing emotional stimuli, particularly odors, is not well understood.
• Odor perception is crucial for survival, influencing approach and avoidance behaviors.

Purpose of the Study:

• To investigate how repeated exposure affects the pleasantness of odors with varying initial pleasantness.
• To determine if the mere exposure effect applies to olfactory stimuli with inherent emotional valence.
• To explore the relationship between initial odor pleasantness and the magnitude of the mere exposure effect.

Main Methods:

• Participants rated the pleasantness, intensity, and familiarity of various odors across multiple sessions.
• Odors varied in their initial pleasantness, ranging from unpleasant to very pleasant.
• Familiarity, pleasantness, and intensity ratings were analyzed in relation to repeated exposure and initial pleasantness.

Main Results:

• Repeated exposure increased familiarity with all tested odors.
• Neutral and mildly pleasant odors showed increased pleasantness ratings after repeated exposure.
• Unpleasant and very pleasant odors were not significantly affected by repeated exposure.
• An inverse U-shaped relationship was observed between initial odor pleasantness and the mere exposure effect's magnitude.

Conclusions:

• The mere exposure effect's impact on odor pleasantness is modulated by the odor's initial pleasantness.
• The phenomenon is limited, particularly for stimuli with strong negative or positive initial valence.
• These findings suggest that the biological relevance of odors may influence the mere exposure effect, impacting attitudinal changes.