Intermodal perception of expressive behaviors by human infants

Abstract

Four experiments demonstrate that infants of 5 and 7 months can detect information that is invariant across the acoustic and optic presentations of a single affective expression. Infants were presented simultaneously with two filmed facial expressions accompanied by a single vocal expression characteristic of one of the facial expressions. The infants increased their looking time to a facial expression when it was sound-specified, as compared to when that filmed expression was projected silently. Even when synchrony relations were disrupted, infants looked proportionately longer to the film that was sound-specified, indicating that some factor other than temporal synchrony guided the infants' looking behavior. When infants viewed the filmed facial expressions either in a normal orientation or upside-down, those infants viewing the facial expressions in the normal orientation looked appropriately, while those viewing the inverted films did not. These findings support the view that infants are sensitive to amodal, potentially meaningful invariant relations in expressive behaviors. These results are discussed in the context of J. J. Gibson's theory of affordances.