Development of Expertise in Face Recognition

The ability to recognize individual faces is a highly specialized skill that emerges during infancy, continues to develop throughout childhood, and becomes adult-like in late adolescence. In this chapter we explore the devel­ opmental progression of face recognition and consider possible mechanisms that underlie it. Specifically, we evaluate the role of visual experience in driving the developmental changes and consider other potential factors that could account for the slow development of adult-like expertise. To begin, we describe the properties of the fully developed adult system for face processing. Adults are experts at face processing. They have the remarkable ability to detect faces, even in the absence of normal facial features. They readily detect faces in paintings in which faces are composed ofobjects such as an arrange­ ment of fruit, vegetables, or rocks (Bruce & Young, 1986), or when presented with a two-tone Mooney face (Kanwisher, Tong, & Nakayama, 1998), at least when the stimuli are upright. Face detection is f~cilitated by the fact that all faces share the same first"order relations: two eyes aligned horizontally above a nose and mouth. As a result, face images can be superimposed, or averaged, and the resulting stimulus remains recognizably face-like (Diamond & Carey, 1986). While adults are proficient at face detection, they recognize faces less often at this basic level (i.e., "that's a face") and more often at the subordinate level (e.g., "that's Wayne Gretzky") and can do so rapidly and accurately (Tanaka, 200 1). This tendency to identify faces more often at the subordinate level is considered a marker of perceptual expertise (Tanaka & Gauthier, 1997). In fact, adults can recognize thousands of individual faces, even when the person is at a distance, in poor lighting, has a new hairdo, or is a former schoolmate who has not been seen for over 20 years (Bahrick, Bahrick, & Wittlinger, 1975). How do newborn infants, who have never before perceived faces, even­ tually acquire the expert ability to recognize thousands of individual faces in adulthood? Here we outline the developmental pattern of face recognition during infancy and childhood, and examine the role of experience in driving the development of this expert system.