Categorical perception of facial expressions: Evidence for a "category adjustment" model

Abstract

Four experiments probed the nature of categorical perception (CP) for facial expressions. A model based on naming alone failed to accurately predict performance on these tasks. The data are instead consistent with an extension of the category adjustment model (Huttenlocher et al., 2000), in which the generation of a verbal code (e.g., "happy") activated knowledge of the expression category's range and central tendency (prototype) in memory, which was retained as veridical perceptual memory faded. Further support for a memory bias toward the category center came from a consistently asymmetric pattern of within-category errors. Verbal interference in the retention interval selectively removed CP for facial expressions, under blocked, but not under randomized presentation conditions. However, verbal interference at encoding removed CP even under randomized conditions and these effects were shown to extend even to caricatured expressions, which lie outside the normal range of expression categories. Copyright 2007 Psychonomic Society, Inc.