A look at how we look at others: Orientation inversion and photographic negation disrupt the perception of human bodies

Although disproportionate inversion effects have often been considered manifestations of the special processes recruited by upright faces, several papers using sequential matching tasks have reported that body postures also produce sizeable inversion effects. However, comparison of inversion effects observed with transient body postures and effects elicited by judgements of facial structure is complicated by qualitative differences between the stimuli and the tasks. Here we report a series of experiments that use attractiveness judgements to provide a better comparison of the effect of inversion as well as contrast negation on face and body perception. Significant effects of inversion and negation were observed for both face and body stimuli. While the magnitude of the inversion effects was broadly comparable, the negation effect was considerably larger for faces. These effects converge with evidence from cognitive neuroscience to suggest that both faces and bodies recruit similar orientation-specific processes distinct from processes used for generic objects.