nan Proietti

The Left Perceptual Bias for adult and infant faces in adults and 5-year-old children: Face age matters

A large number of studies have shown that adults rely more heavily on information conveyed by the left side of the face in judging emotional state, gender and identity. This phenomenon, called left perceptual bias (LPB), suggests a right hemisphere lateralization of face processing mechanisms. Although specialization of neural mechanisms for processing over-experienced face categories begins during the first year of life, little is known about the developmental trajectory of the LPB and whether or when the bias becomes selective for specific face categories as a result of experience. To address these questions we tested adults (Experiment 1) and 5-year-old children (Experiment 2) with null or limited experience with infants in an identity matching-to-sample task with chimeric adult and infant faces, for which both adults and children have been shown to manifest differential processing abilities. Results showed that 5-year-olds manifest a leftward bias selective for adult faces, and the magnitude of the bias is larger for adult compared to infant faces in adults. This evidence is in line with earlier demonstrations of a perceptual processing advantage for adult faces in adults and children and points to the role of experience in shaping neurocognitive specialization for face processing.

Searching for faces of different ages: Evidence for an experienced-based own-age detection advantage in adults.

Previous studies have shown that attention deployment in visual search tasks is modulated by face race and emotional expression, with a search asymmetry in favor of those faces that are less efficiently discriminated and recognized at the individual level (i.e., other-race faces and angry faces). Face age is another dimension affecting how faces are remembered, as it has been widely reported that young adults show significant deficits in recognizing other-age faces. By comparing adults search efficiency for own- and other-age faces in a visual search task in which face age was the target feature we explored whether the mirror pattern of detection and recognition effects found for race biases generalizes to age biases, and whether search efficiency for adult and nonadult faces is modulated by experience accumulated with nonadult faces. Search efficiency was greater for adult faces than for infant (Experiment 1) or child faces (Experiment 2) in adults with limited experience with infants or children, whereas there was no sign of search asymmetry in preschool teachers who have had extensive recent experience with children (Experiment 2). Results indicate that the influence of age on attention deployment parallels the effects that this face attribute has on face recognition, and that both effects are experience-based.