Effects of inversion and negation on social inferences from faces

Judgments about personality and other social characteristics based on facial appearance are remarkably consistent across individuals. However, whereas the facial cues that underpin age and sex judgments are already well understood, the physical bases for judgments of characteristics such as intelligence or trustworthiness are still unknown. Inversion and photographic negation are used here to investigate the visual processes underlying social inferences from the face and to explore whether various judgments might rely on different perceptual representations. In experiment 1, the perceptions of age, sex, attractiveness, approachability, intelligence, and trustworthiness, but not distinctiveness, were affected by inversion, and all these characteristics were affected by negation. The effects of inversion and negation were independent, suggesting that they impaired the encoding of different types of information. Moreover, an independent manipulation of hue and luminance in experiment 2 showed that the effects of negation were mainly due to the reversal of luminance values. These results are consistent with the view that information about the configuration of features (the processing of which is impaired by inversion) and information about surface properties (the processing of which is impaired by brightness negation) are both used in the perception of social characteristics from faces. In addition, the fact that there was a similar pattern of impairment across most judgments suggests that there is an initial common perceptual representation of the face, from which most characteristics are inferred.