Arousal, valence, and discrete categories in facial emotion

The aim of this study was to investigate the relationship between the categorical recognition of emotional facial expressions and two affective dimensions, arousal and valence, as well as other facial characteristics, such as gender and age. To achieve this goal, participants were asked to evaluate expressive faces from two databases (the Karolinska Directed Emotional Faces and FACES) along the dimensions of arousal and valence, in addition to completing an emotional categorization task. The results revealed variations in overall arousal and valence levels across different emotional categories. Most notably, they demonstrated that the three assessments were interdependent: the positive or negative valence of facial expressions was found to be a function of arousal level for all emotional category except surprise, whereas the accuracy of categorization into discrete categories was influenced by both arousal and valence level. Furthermore, the gender and age of the faces influenced evaluations across all three tasks - arousal ratings, valence ratings, and categorization. The implications of these findings for the study of facial emotion recognition mechanisms are discussed.