Abstract
Recent work has demonstrated that the range of face recognition ability is very large, with developmental prosopagnosics at the low end (who in severe cases have difficulty identifying nuclear family members) and super-recognizers at the high end (who report rarely forgetting a face). It is not known what underlies this variation. One possibility is that lower-level perceptual abilities predict face recognition ability. Shape and pigmentation (surface reflectance) information have been shown to be about equally useful for face recognition by normal observers. This study seeks to determine whether this is also the case for people with very good and very bad face recognition ability, in order to determine whether face recognition ability is selectively associated with ability to perceive face shape or face pigmentation. Here we report findings from prosopagnosics and super-recognizers as well as normal control subjects. Subjects performed a facial similarity task, in which they sorted a set of faces in order of similarity to a target face. In the pigmentation condition all the faces had the same shape but different pigmentation, so that use of pigmentation information was required to perform the task. In the shape condition all the faces to be sorted had the same pigmentation but different shape, so that use of shape information was required to perform the task. By comparing performance by developmental prosopagnosics, normal control subjects, and super-recognizers on the shape and pigmentation conditions, we can determine whether shape or pigmentation perception is associated with face recognition ability.