TY - JOUR
T1 - The role of structural facial asymmetry in asymmetry of peak facial expressions
AU - Schmidt, Karen L.
AU - Liu, Yanxi
AU - Cohn, Jeffrey F.
N1 - Funding Information:
Address correspondence to: Karen L. Schmidt, Department of Psychiatry, University of Pittsburgh, 121 University Place, Pittsburgh PA 15217, USA. E-mail: [email protected] This study is part of a larger programme of research that is ongoing in the Department of Psychiatry at the University of Pittsburgh, in collaboration with the Department of Computer Science and the Robotics Institute at Carnegie Mellon University. This study was supported in part by grants from the National Institute of Mental Health (MH 15279 and MH067976 (K. Schmidt) and MH51435 (J. Cohn). Additional support for this project was received from Office of Naval Research (HID 29-203). The authors acknowledge the contribution of Rebecca McNutt to this article. A preliminary version of these results was presented at the Tenth Annual Conference: Facial Measurement and Meaning in Rimini, Italy, September 2003.
PY - 2006/11
Y1 - 2006/11
N2 - Asymmetric facial expression is generally attributed to asymmetry in movement, but structural asymmetry in the face may also affect asymmetry of expression. Asymmetry in posed expressions was measured using image-based approaches in digitised sequences of facial expression in 55 individuals, N = 16 men, N = 39 women. Structural asymmetry (at neutral expression) was higher in men than women and accounted for .54, .62, and .66 of the variance in asymmetry at peak expression for joy, anger, and disgust expressions, respectively. Movement asymmetry (measured by change in pixel values over time) was found, but was unrelated to peak asymmetry in joy or anger expressions over the whole face and in facial subregions relevant to the expression. Movement asymmetry was negatively related to peak asymmetry in disgust expressions. Sidedness of movement asymmetry (defined as the ratio of summed movement on the left to movement on the right) was consistent across emotions within individuals. Sidedness was found only for joy expressions, which had significantly more movement on the left. The significant role of structural asymmetry in asymmetry of emotion expression and the exploration of facial expression asymmetry have important implications for evolutionary interpretations of facial signalling and facial expressions in general.
AB - Asymmetric facial expression is generally attributed to asymmetry in movement, but structural asymmetry in the face may also affect asymmetry of expression. Asymmetry in posed expressions was measured using image-based approaches in digitised sequences of facial expression in 55 individuals, N = 16 men, N = 39 women. Structural asymmetry (at neutral expression) was higher in men than women and accounted for .54, .62, and .66 of the variance in asymmetry at peak expression for joy, anger, and disgust expressions, respectively. Movement asymmetry (measured by change in pixel values over time) was found, but was unrelated to peak asymmetry in joy or anger expressions over the whole face and in facial subregions relevant to the expression. Movement asymmetry was negatively related to peak asymmetry in disgust expressions. Sidedness of movement asymmetry (defined as the ratio of summed movement on the left to movement on the right) was consistent across emotions within individuals. Sidedness was found only for joy expressions, which had significantly more movement on the left. The significant role of structural asymmetry in asymmetry of emotion expression and the exploration of facial expression asymmetry have important implications for evolutionary interpretations of facial signalling and facial expressions in general.
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U2 - 10.1080/13576500600832758
DO - 10.1080/13576500600832758
M3 - Article
C2 - 16966242
AN - SCOPUS:33748536390
SN - 1357-650X
VL - 11
SP - 540
EP - 561
JO - Laterality
JF - Laterality
IS - 6
ER -