Emotion Categories and Dimensions in the Facial Communication of Affect: An Integrated Approach

We investigated the role of facial behavior in emotional communication, using both categorical and dimensional approaches. We used a corpus of enacted emotional expressions (GEMEP) in which professional actors are instructed, with the help of scenarios, to communicate a variety of emotional experiences. The results of Study 1 replicated earlier findings showing that only a minority of facial action units are associated with specific emotional categories. Likewise, facial behavior did not show a specific association with particular emotional dimensions. Study 2 showed that facial behavior plays a significant role both in the detection of emotions and in the judgment of their dimensional aspects, such as valence, arousal, dominance, and unpredictability. In addition, a mediation model revealed that the association between facial behavior and recognition of the signaler's emotional intentions is mediated by perceived emotional dimensions. We conclude that, from a production perspective, facial action units convey neither specific emotions nor specific emotional dimensions, but are associated with several emotions and several dimensions. From the perceiver's perspective, facial behavior facilitated both dimensional and categorical judgments, and the former mediated the effect of facial behavior on recognition accuracy. The classification of emotional expressions into discrete categories may, therefore, rely on the perception of more general dimensions such as valence and arousal and, presumably, the underlying appraisals that are inferred from facial movements.