The intensity of facial expression is determined by underlying affective state and social situation.

Abstract

The present study concerned the influence of the presence of others on facial expressions of emotion. The proposition that facial expressive displays are better predicted by the social context than by emotional state (A. J. Fridlund, 1991) was tested in an experiment varying both the sociality of the context and the intensity of the emotion elicitor as well as the relationship between expressor and audience. The results indicate that the intensity of expressive displays cannot be satisfactorily predicted by either of these factors alone but is influenced by a complex interplay of all 3 factors.

The thrill of victory and the agony of defeat: Spontaneous expressions of medal winners of the 2004 Athens Olympic games.

“…These data provide further support for the view that Duchenne smiles are associated with enjoyable emotions Hess et al, 1995;Keltner & Bonanno, 1997;Smith, 1995). Because no other expression was as dominant among the victors, the data also suggest that the Duchenne smile may be the only facial marker of different types of enjoyable emotions (Ekman, 2003), including fiero-the joy of victory.…”

Describing the emotional states that are expressed in speech

“…Instead, all expressive displays, even those that take place in private, involve social motives. Complementing FridlundÕs contentions about the social nature of facial displays of emotion, Hess et al (1995) found that facial expressions of emotion as indexed by four muscle groups was influenced by the type of eliciting stimulus involved (two films that differed in their degree of funniness), sociality (whether participants viewed the film alone or with another person), and the relationship between participants (friends versus strangers).…”

The Social Effects of Emotions are Functionally Equivalent Across Expressive Modalities

“…Indeed, from a pragmatic standpoint, understanding the social consequences of emotional expressions is more fruitful than quibbling about whether facial displays reflect felt emotions or social motives, especially because emotion and motivation are two sides of the same coin-emotions arise in response to events that matter in light of one's goals and concerns (Frijda, 1986;Lazarus, 1991), and therefore emotions, by their very nature, reflect underlying motivations (Buck, 1985;Parkinson, 2005). In that sense, the basic emotion perspective and the behavioral ecology perspective can be seen as compatible (Buck, 1994;Frijda, 1995;Hess, Banse, & Kappas, 1995;Horstmann, 2003); they merely emphasize different parts of the emotivational processes that put us in motion and that allow us to adaptively engage with our social environment.…”