Facial Mimicry of Spontaneous and Deliberate Duchenne and Non-Duchenne Smiles

Increasing evidence suggests that Duchenne (D) smiles may not only occur as a sign of spontaneous enjoyment, but can also be deliberately posed. The aim of this paper was to investigate whether people mimic spontaneous and deliberate D and non-D smiles to a similar extent. Facial EMG responses were recorded while participants viewed short video-clips of each smile category which they had to judge with respect to valence, arousal, and genuineness. In line with previous research, valence and arousal ratings varied significantly as a function of smile type and elicitation condition. However, differences in facial reactions occurred only for smile type (i.e., D and non-D smiles). The findings have important implications for questions relating to the role of facial mimicry in expression understanding and suggest that mimicry may be essential in discriminating among various meanings of smiles.     

Temporal Aspects of Facial Displays in Person and Expression Perception: The Effects of Smile Dynamics,Head-tilt,and Gender

Recent work suggests that temporal aspects of facial displays influence the perception of the perceived authenticity of a smile. In the present research, the impact of temporal aspects of smiles on person and expression perception was explored in combination with head-tilt and gender. One hundred participants were shown different types of smiles (slow versus fast onset) in combination with three forms of head-tilt (none, left, or right) exhibited by six computer-generated male and female encoders. The encoders were rated for perceived attractiveness, trustworthiness, dominance, and the smiles were rated for flirtatiousness and authenticity. Slow onset smiles led to more positive evaluations of the encoder and the smiles. Judgments were also significantly influenced by head-tilt and participant and encoder gender, demonstrating the combined effect of all three variables on expression and person perception.

Acting Surprised: Comparing Perceptions of Different Dynamic Deliberate Expressions

Journal of Nonverbal Behavior - People are accurate at classifying emotions from facial expressions but much poorer at determining if such expressions are spontaneously felt or deliberately posed....     

Effects of Dynamic Attributes of Smiles in Human and Synthetic Faces: A Simulated Job Interview Setting

We examined the effects of the temporal quality of smile displays on impressions and decisions made in a simulated job interview. We also investigated whether similar judgments were made in response to synthetic (Study 1) and human facial stimuli (Study 2). Participants viewed short video excerpts of female interviewees exhibiting dynamic authentic smiles, dynamic fake smiles, or neutral expressions, and rated them with respect to a number of attributes. In both studies, perceivers’ judgments and employment decisions were significantly shaped by the temporal quality of smiles, with dynamic authentic smiles generally leading to more favorable job, person, and expression ratings than dynamic fake smiles or neutral expressions. Furthermore, authentically smiling interviewees were judged to be more suitable and were more likely to be short-listed and selected for the job. The findings show a high degree of correspondence in the effects created by synthetic and human facial stimuli, suggesting that temporal features of smiles similarly influence perceivers’ judgments and decisions across the two types of stimulus.

When Memory is Better for Out-group Faces: On Negative Emotions and Gender Roles

Memory for in-group faces tends to be better than memory for out-group faces. Ackerman et al. (Psychological Science 17:836–840, 2006) found that this effect reverses when male faces display anger, supposedly due to their functional value in signaling intergroup threat. We explored the generalizability of this reverse effect. White participants viewed Black and White male or female faces displaying angry, fearful, or neutral expressions. Recognition accuracy for White male faces was better than for Black male faces when faces were neutral, but this reversed when the faces displayed anger or fear. For female targets, Black faces were generally better recognized than White faces, and female faces were better remembered when they displayed anger rather than fear, whereas male faces were better remembered when they displayed fear rather than anger. These findings are difficult to reconcile with a functional account and suggest (a) that the processing of male out-group faces is influenced by negative emotional expressions in general; and (b) that gender role expectations lead to differential remembering of male and female faces as a function of emotional expression.     

Moving Smiles: The Role of Dynamic Components for the Perception of the Genuineness of Smiles

Three experiments were conducted to examine whether the temporal dynamics of Duchenne-smiles influenced the perception of smile authenticity. Realistic computer-generated Duchenne-smiles that varied in their onset- and offset-durations (Experiment 1), or only in their offset-duration (Experiment 2), or in both their onset- and apex-durations (Experiment 3), were created using Poser 4 software. Perceived genuineness varied monotonically with the duration of each manipulated dynamic component. The results are in accordance with Ekman and Friesens (1982) observations regarding the duration of smiles of enjoyment, which suggest that each dynamic component has a distinct duration range that can influence the perceived genuineness of smiles.We wish to thank Jesse Spencer-Smith for sharing the AU morph targets that have been developed in the context of his research.