Original Papers Spontaneous Facial Mimicry, Liking and Emotional Contagion

Mimicking expressions is a phylogenetically ancient and basic form of intraspecies communication (Brothers, 1990); it may have been evolutionarily adaptive because it helped humans communicate and foster relationships (Lakin, Jefferis, Cheng, & Chartrand, 2003). When an observer matches the facial expression of another, emotion-related thoughts and feelings may be modulated or initiated in the observer (McIntosh, 1996; McIntosh, Druckman, & Zajonc, 1994). Thus, mimicry appears to play a role in such intertwined and basic social processes as emotional contagion (Hatfield, Cacioppo, & Rapson, 1992; Lundquist & Dimberg, 1995; McIntosh et al., 1994; Vaughan & Lanzetta, 1981), dyadic rapport (Capella, 1993), behaviors such as helping and generosity (van Baaren, Holland, Kawakami, & van Knippenberg, 2004), and the perception and interpretation of facial expressions of emotion (Niedenthal, Brauer, Halberstadt, & Innes-Ker, 2001). Moreover, mimicry appears impaired in autism, a disorder of social-emotional functioning (McIntosh, Reichmann-Decker, Winkielman & Wilbarger, 2006), and some theorize that this deficit may cause some of the symptoms evident in autism (Moody & McIntosh, in press). The importance of mimicry for interpersonal and emotional processes has generated significant work in recent years; however, basic issues such as the extent of mimicry of live (not photographed or videotaped) models and variables that moderate the extent of mimicry are relatively unexplored. The present studies address these questions. They focus on facial mimicry, as most investigations of mimicry have concentrated on the face (Hess, Philippot, & Blairy, 1998), and the best evidence for the role of mimicry in emotional contagion is associated with facial mimicry (Hatfield et al., 1992). Numerous studies document that people mimic. For example, presentations of posed faces Daniel N. McIntosh*