The role of external features for person recognition

Face recognition is a remarkable human skill, as we are able to remember many thousands of faces. A great deal of research has investigated how it is possible to achieve such high levels of performance and what kind of information we encode to reach such a level of proficiency [Bruce and Young 1986]. One important distinction that is made in the literature is the distinction between external and internal facial features. Internal facial features refer to the size and outline of the eyes and mouth and their configuration. External facial features rather denote the shape of the face or the hairstyle associated with a particular face [Ellis et al. 1979]. Here, we explore this issue in the context of motion, an area that has only recently begun to concern face researchers [O'Toole et al. 2002; Knappmeyer et al. 2003]. In our displays avatars were animated to approach the observer in depth. Intuitively internal features are likely to play less of a role when a person is far away. Conversely, external features such as gait and clothing are likely to be more important if the person to recognize is further away.