The good, the bad, and the average: Characterizing the relationship between face and object processing across the...

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. In the present study, we investigate whether a group of good face recognizers (high performers; HPs) perform qualitatively differently from a control group on tests of face, object and word recognition, and also compare them to a group of developmental prosopagnosics (DPs). Through a series of experiments, we (i) examine whether HPs are better than control subjects in face and object recognition, (ii) investigate if any dissociations among face, object, and word processing tasks can be demonstrated in the HPs, and (iii) compare the performance of the HPs to a group of poor face recognizers namely a group of DPs. Data from this DP group have previously been reported, but the analyses presented here are new. We find that HPs were significantly better than matched control subjects on tests of face and object recognition including a reading task, but they did not show significantly larger inversion effects on typical tests of face processing (the CFMT and the CFPT). There was no evidence of dissociations between face and object processing in the HPs when compared to controls, indicating superior performance across visual domains. In the DP group, however, we found significant dissociations between face and object recognition performance on a group level, indicating that face processing is disproportionally affected. On this basis, we propose that superior face processing in HPs rely on more general cognitive or perceptual processes shared with object processing. Hence, while face processing in DPs seems qualitatively different from the normal population, there is no such difference between average and high performing face recognizers. Thus, what underlies superior face processing in HPs might also underlie their superior performance with other stimulus classes and might be conceived as a general factor in the visual domain, a VG-factor, akin to the G factor in intelligence.