Non-rigid facial movement facilitates holistic processing of emotional faces: the role of additional emotional intensity and temporal information

Previous studies have shown that emotional faces are perceived as a whole entity. However, most studies focused on how static emotional faces are processed, leaving a gap in our understanding of how dynamic emotional faces are processed. This study aimed to explore the influence of non-rigid facial movement (dynamic; i.e., from neutral to 100% emotional intensity) on the holistic processing of emotional faces using the congruency effect. Participants were tasked with identifying the emotional expression of either the top or bottom half of a dynamic or static composite emotional face. The results showed that when faces were upright, dynamic emotional faces demonstrated a larger congruency effect compared to single-static faces, while the multi-static condition did not differ from dynamic or single-static conditions. When faces were inverted, the congruency effect was observed in the dynamic condition, but it was absent in both the single-static and multi-static conditions. These findings collectively suggest that non-rigid facial movement amplifies the holistic processing of emotional faces through the combined role of additional emotional intensity and temporal information.