Understanding Empathy from Interactional Synchrony in Humans and Non-human Primates

Abstract

Humans are highly responsive to social partners. Either consciously or unconsciously, humans adjust one’s own behavior to match with those of others. Moreover, humans can predict others’ intention or desire and often behave in a prosocial way to help themselves. A comparative approach is one of the powerful tools to understand the evolutionary origins of these social behaviors in humans, including emotional contagion, sympathetic concern, perspective-taking and targeted helping behaviors, and its relationship to each other. Among these social behaviors, an ability for the coordinated movements with others (i.e., interpersonal coordination) has been postulated as the most essential to the other social behaviors. Interpersonal coordination includes two types of behavior: mimicry and interactional synchrony. Mimicry is matching a type of the behavior, such as body postures or facial expressions. In contrast, interactional synchrony is matching the timing of behavior. Relative to the studies on mimicry, there are few studies on interactional synchrony in non-human primate species possibly due to the difficulties in establishing a methodology. In this chapter, we present gradually the increasing number of studies on interactional synchrony in humans and non-human primates. The findings demonstrate that the ability for interactional synchrony is shared across humans, chimpanzees, bonobos, and macaques. The latest findings from a direct comparison between humans and chimpanzees further demonstrate that there are both similarities and significant differences on the ability between two species. At the end of this chapter, we suggest a future direction of the comparative studies on interactional synchrony.