Facial Expression 1 Running head: DYNAMICS OF FACIAL EXPRESSION OF EMOTION Dynamics of Facial Expression Influence Observer Judgments of Intensity of Emotion

How do the dynamics of motion in facial expressions influence the intensity of affect attributed by an observer? Ratings of happiness for videotaped smiles were compared with ratings of still photos excerpted from the same stimuli. About 30 participants per stimulus (124 total) rated intensity of emotion using a scale from 1 to 5 (“not at all happy” to “extremely happy”). Twotailed ANOVA showed significantly higher happiness ratings for still stimuli (M = 4.17, SD = .647) compared to moving stimuli (M = 3.85, SD = .743), F(1, 245) = 12.69, p = .00 for two posers. Significantly higher ratings for still photos occurred at varying video segment lengths, as confirmed by contrast analysis, t(239) = 3.74, p = .00. Because facial expression dynamics clearly influence affect intensity judgments, responses to dynamic stimuli may be more complex and thus more difficult to interpret than still photos. Possible models of attribution are discussed.