Abstract
Adaptation to faces can generate after-effects in the perception of facial configuration, identity, attractiveness, race and gender. Here, we investigate what level of the visual processing hierarchy mediates the effect of face adaptation on perceived gender. Subjects were presented with adapting stimuli alternating between male faces at one orientation and female faces at the opposite orientation. Their task was to report the gender of test faces drawn from a continuum morphed between average male and female faces. We found that opposite after-effects for judgments of face gender can be induced simultaneously for upright and inverted faces such that the point of subjective androgyny is shifted towards the adapting faces of the same orientation. These after-effects are robust to changes in face size between adaptor and test, ruling out adaptation of a low-level encoding mechanism. Opposite after-effects of perceived gender can also be induced for faces tilted + and −90deg from upright. The existence of these orientation-contingent after-effects indicates that dissociable populations of neurons mediating the after-effect at each orientation are susceptible to the same form of adaptive normalization, suggesting that adaptation is occurring at a view dependent stage of face processing.