Abstract
Mondloch et al (Psychological Science, 1999) report that newborns (but not 3-month-olds) prefer a simple schematic face with internal features in a normal orientation versus the same face with the internal features inverted. Older infants (but not newborns) prefer a more complex schematic face with normal phase versus the same face with a 180 phase shift. One interpretation of these results is that there are two qualitatively different mechanisms involved in face perception at birth versus 3-months of age. Adult's identification of natural faces may be qualitatively similar across eccentricity (Makela et al, Vision Research, 2001). We evaluated whether adult processing of the schematic faces employed in the infant studies is similar across eccentricity. In the preliminary study, naïve untrained adults (n=20) viewed pairs of schematic faces at 40 degrees eccentricity and indicated which face appeared most “normal”. In the main conditions, each pair differed only in orientation of the internal features. The upright internal orientation was judged “normal” significantly more often in complex schematic pairs compared to simple schematic pairs. (No differences were observed in subsequent foveal judgments.) To examine sensitivity to the orientation cue, two trained observers performed a two-alternative forced-choice discrimination task. Stimuli were low contrast pairs of identical simple or complex schematic faces with 0 versus 180 degree orientation of the internal orientation of the facial features. Pairs were presented at 0, 15, 31, and 38 degrees eccentricity. Orientation discrimination for complex faces was similar across conditions, but discrimination for simple faces was strongly reduced with eccentricity. These results suggest a different effect of eccentricity for faces that newborns differentiate compared to faces that older infants differentiate. Implications of this result for the development of face perception will be discussed.