The Many Faces of a Neutral Face: Head Tilt and Perception of Dominance and Emotion

Based on the premise that human head tilt is homologous to animal dominance displays, we hypothesized that when a head is bowed, the face should be perceived as submissive, sad, displaying inferiority emotions (i.e., shame, embarrassment, guilt, humiliation, and respect) and, paradoxically, as contracting the zygomatic major muscle. Conversely, a raised head should be perceived as more dominant and displaying greater superiority emotions (i.e., contempt and pride). We conducted two experiments showing 3-D models of faces to 64 participants. The results confirmed our hypotheses and also showed that a raised head connotes happiness. In addition, we found a significant influence of the actors' sex on participants' perception, such as a bias towards perceiving stronger upward contraction of the mouth in female than male actors when the head is tilted. We discuss these findings within the context of evolution and social behavior.