Face recognition skills vary considerably both in the normal population and in various clinical groups, and understanding the cognitive mechanisms contributing to this variability is important. Here, we examine whether good face recognisers (high performers, HPs) perform better than controls on tests of face, object and word recognition, and whether these domains may be dissociated in HPs. Also, we address the same questions in a group of developmental prosopagnosics (DPs) using the same tests.
HPs performed significantly better than matched controls on tests of face and object recognition, as well as a reading test, and there was no evidence of dissociation between these domains. In the DP group, we did find a significant dissociation between face and object recognition and reading performance, indicating that face processing was disproportionally affected in this group.
This suggests that face recognition in DPs may be qualitatively different from the normal population. In contrast, the superior performance of HPs is not specific for faces, but persists across visual domains. On this basis, we propose that superior face processing in HPs relies on more general cognitive or perceptual processes shared with object processing. These may be conceived as a general factor in the visual domain.