Facial mimicry depends on the emotion we recognize in others' faces.

Facial mimicry is known to play an important role in emotional communication. While major models of facial mimicry assume a relationship between facial mimicry and emotion recognition, the empirical evidence for such a relationship is mixed. In this study, the facial movements of the same participants were compared when they recognised the same uncertain faces as "happiness" or "anger." When faces expressed anger in the upper half (upper anger) and happiness in the lower half (lower happiness), participants responded that it was "happiness" in some trials and "anger" in others. The electromyography data showed that participants frowned more in trials in which they recognised anger in the upper anger and lower happiness faces than in trials in which they recognised happiness in the same faces (Experiment 1). By presenting the upper and lower half of expressions individually, we confirmed that upper anger and lower happiness were both salient in the expression intensity and that both the upper and lower half of the faces individually induced emotionally congruent facial movements (Experiment 2). Despite limitations, this study supported the relationship between facial mimicry and emotional recognition. These findings aid in further understanding social interaction at an unconscious and physical level.