The present work examined the role of inner and outer features in infants' failure to recognize inverted faces and in their recognition of upright ones (the "inversion effect"). The first study established that the inversion effect is present in infants as young as 5 months; study 2 and study 3 demonstrated a developmental shift in the basis of this effect between 5 and 7 months. In the second study, 7-and 9-month-olds, but not 5-month-olds, could recognize a face that had its external features inverted but its internal ones upright. In the third study, 7-and 9-month-olds, but not 5-month-olds, could recognize upright faces as long as their internal features remained the same, even when the external features were new. Taken together, these studies suggest that the importance of internal features for face recognition increases between 5 and 7 months.
Keywords infants; inversion effect; face perceptionFace recognition is a remarkable human achievement that is crucial for social development. Faces are highly salient and biologically significant stimuli. As a species, humans appear primed to prefer faces, or face-like stimuli, from birth (Fantz, 1964;Goren, Sarty, & Wu, 1975 ). For example, newborns prefer faces to patterns and prefer a face-like structure made up of three blobs, arranged as two 'eyes' above a 'mouth,' to other arrangements of the same elements (Simion, Valenza, Macchi Cassia, Turati, & Umilta, 2002;Turati, Simion, Milani, & Umilta, 2002;Valenza, Simion, Macchi Cassia, & Umilta, 1996). Young infants are also able to recognize individual faces, preferring their mother's face to that of a stranger in the first few days of life (Bushnell, 2003;Bushnell, Sai, & Mullen, 1989;Johnson & Morton, 1991;Pascalis, deSchonen, Morton, Deruelle, & Fabre-Grenet, 1995).In adults, face recognition is considered to be primarily dependent on configural or holistic processing, focusing more on the relation between facial features (eyes, nose, mouth, chin, ears, hairline, etc.) than the individual features themselves , see also (Carey & Diamond, 1994;Farah, Wilson, Drain, & Tanaka, 1998;Moscovich & Moscovich, 2000;Moscovich, Winocur, & Behrmann, 1997). Three different types of configurational information figure prominently in face perception: (1) first order relations, which refer to cardinal top-down ordering of features shared by all faces -eyes above noseCorresponding author: Susan A. Rose, Albert Einstein College of Medicine, Department of Pediatrics, 1300 Morris Park Ave, Bronx, New York, 10461, Phone # (718) Fax # (718) 518-8544, email: srose@aecom.yu.edu. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disc...