Abstract
A fundamental hallmark of face perception is the disproportionate face inversion effect: the finding that stimulus inversion disrupts perception of faces more than perception of non-faces (Yin, 1969). This effect is commonly viewed as evidence that perception of upright and inverted faces rely on at least partially distinct mechanisms, whereas perception of upright and inverted non-faces rely on largely similar mechanisms. At the individual differences level, this view predicts that perception of upright and inverted stimuli should correlate less for faces than for non-faces. This prediction was tested in three experiments. In Experiment 1 (n = 82), the upright-inverted correlation is larger for faces (0.71) than for bodies (0.23). In Experiment 2 (n = 90), the upright-inverted correlation is similar for faces (0.30) and for bodies (0.28). In Experiment 3 (n = 72), the upright-inverted correlation is similar for faces (0.56) and for houses (0.56). Contrary to the prediction, we consistently found no evidence of a weaker upright-inverted correlation for faces than for non-faces, indicating no disproportionate inversion effect for faces at the individual differences level. Our results cannot be accounted by task-related issues, because we obtained disproportionate face inversion effects at the group level, replicating the standard finding in the literature. Neither can they be accounted by reliability issues, because the reliabilities of the face and non-face tasks are comparable especially in Experiments 2 and 3. Finally, our study was not underpowered, because the sample size of our three experiments allowed us to detect moderate effects with at least 0.80 probability. Our findings indicate that although perception of upright and inverted faces differ in important ways, they may not always dissociate more than perception of upright and inverted non-faces do.
Meeting abstract presented at VSS 2013