Affect and face perception: odors modulate the recognition advantage of happy faces.

Previous choice reaction time studies have provided consistent evidence for faster recognition of positive (e.g., happy) than negative (e.g., disgusted) facial expressions. A predominance of positive emotions in normal contexts may partly explain this effect. The present study used pleasant and unpleasant odors to test whether emotional context affects the happy face advantage. Results from 2 experiments indicated that happiness was recognized faster than disgust in a pleasant context, but this advantage disappeared in an unpleasant context because of the slow recognition of happy faces. Odors may modulate the functioning of those emotion-related brain structures that participate in the formation of the perceptual representations of the facial expressions and in the generation of the conceptual knowledge associated with the signaled emotion.