When preschoolers follow their eyes and older children follow their noses: visuo-olfactory social affective matching in childhood.

Recognition of emotional facial expressions is a crucial skill for adaptive behavior that most often occurs in a multi-sensory context. Affective matching tasks have been used across development to investigate how people integrate facial information with other senses. Given the relative affective strength of olfaction and its relevance in mediating social information since birth, we assessed olfactory-visual matching abilities in a group of 140 children between the ages of 3 and 11 years old. We presented one of three odor primes (rose, fish and no-odor, rated as pleasant or unpleasant by individual children) before a facial choice task (happy vs. disgusted face). Children were instructed to select one of two faces. As expected, children of all ages tended to choose happy faces. Children younger than 5 years of age were biased towards choosing the happy face, irrespective of the odor smelled. After age 5, an affective matching strategy guided children's choices. Smelling a pleasant odor predicted the choice of happy faces, whereas smelling the unpleasant or fish odor predicted the choice of disgusted faces. The present study fills a gap in the developmental literature on olfactory-visual affective strategies that affect decision-making, and represents an important step towards understanding the underlying developmental processes that shape the typical social mind.