Processing faces in dyadic and triadic contexts.

In a series of four experiments we assessed whether functional properties of the human face, such as signaling an object through eye gaze, influence face processing in 3- and 4-month-old infants. Infants viewed canonical and scrambled faces. We found that 4- but not 3-month-old infants' ERP showed an enhanced face-sensitive N170 component for the scrambled stimulus. Furthermore, when canonical and scrambled faces were gazing toward an object, 4-month-olds displayed an enhanced Negative central (Nc) component, related to attentional processes, for the scrambled face. Three-month-olds did not display any of these effects. These results point to important transition in the first months of infancy and show that triadic cues influence the processing of the human face.