Emotion Processing in Homo and Pan

Evolution prepared group-living species, (non)human primates included, to quickly recognize and adequately respond to conspecifics’ emotional expressions. Different theories propose that mimicry of emotional expressions facilitates these swift adaptive reactions. When species unconsciously mimic their companions’ expressions of emotion, they come to feel reflections of their emotions that influence emotional and empathic behavior. The majority of emotion research has focused on full-blown facial expressions of emotion in humans. However, facial muscles can sometimes be controlled; humans know when to smile, and when not to. Moreover, the fact that emotions are not just expressed by the face alone but by the whole body is often still ignored. In this talk, I therefore argue for a broader exploration of emotion signals from sources beyond the face or face muscles that are more difficult to control. More specifically, I will argue that implicit sources including the whole body and subtle autonomic responses including pupil-dilation are picked up by observers and influence subsequent behavior. Across different primate species, seeing a conspecific being emotional and expressing that in one way or another, immediately and automatically attracts attention, yields mimicry and triggers action tendencies in observers. In my research, I take a comparative approach and investigate similarities and differences in the perception of emotions between humans, chimpanzees (Pan troglodytes) and bonobos (Pan Paniscus). I will here discuss new, recently collected data and suggest avenues for future research that will hopefully eventually lead to a better comprehension of emotional expressions and how we come to understand each other’s emotions.