The writing of this chapter has been facilitated by grants from the “Fonds National de la Recherche Scientifique de Belgique” 8.4510.99 and 8.4510.03 and by a grant ARC 96/01-198 from the University of Louvain. The authors appreciate the helpful comments of Ursula Hess on earlier drafts of this chapter. Correspondence regarding this chapter should be addressed to Pierre Philippot, Faculté de Psychologie, Université de Louvain, place du Cardinal Mercier, 10, B-1348 Louvain-la-Neuve, Belgique. Electronic mail may be sent via Internet to Pierre.Philippot@psp.ucl.ac.be.
A crucial role of facial expressions is to convey one's feeling to facilitate interpersonal or intergroup understanding and interactions (Kirouac & Hess, 1999; Philippot, Feldman, & Coats, 1999). Indeed, the exchange of nonverbal information in human interactions serves not only to inform interaction partners of each other's emotional (Ekman, Friesen, & Ellsworth, 1982; Hess, Kappas, & Scherer, 1988; Noller, 1985; Russell, 1994) or intentional states (Frijda, 1986; Frijda & Tcherkassof, 1997; Tcherkassof, 1999) but also to regulate aspects of social relationships (Kirouac & Hess, 1999).
In this context, a small body of research has established that facial expressions of emotions (e.g., anger, disgust, fear, happiness and sadness) affect decoders' interpersonal trait inferences, such as inferences of dominance, affiliation or romantic interest (Eibl-Eibesfeldt, 1989; Hess, Blairy, & Kleck, 2000; Keating, 1985; Keltner, Young, Oemig, Heerey, & Monarch, 1998; Knutson, 1996) or of perceived intelligence, attractiveness and sociability (Matsumoto & Kudoh, 1993; Riggio & Friedman, 1986).