Categorical perception is not a hallmark of fast initial processing of facial expressions of emotions

Abstract

Initial processing of facial expressions of emotions has been shown to occur very fast, even without awareness. In order to determine whether the fast initial processing of facial expressions is categorical, we investigated temporal characteristics of categorical perception (CP) of facial expressions. We examined the effects of shortening stimulus duration on participant performance with respect to identifying (Experiment 1) and discriminating (Experiment 2) morphed facial expressions. Results of the two experiments suggested that CP was attenuated or even disappeared when facial stimuli were presented for as briefly as 50-75 milliseconds. These findings suggest that CP may be irrelevant in the fast initial processing of facial expressions.View full abstract