Department of Psychology, Senshu University , Kawasaki , Japan.
Laterality. 2019 Nov;24(6):678-696. doi: 10.1080/1357650X.2019.1590381. Epub 2019 Mar 5.
Cheater detection, which is a prerequisite for the evolution of social cooperation, has been successfully simulated in laboratory settings. However, the process has not been perfect because the detection rate has usually been just above chance. The present study investigated the role of lateral posing biases and emotional expressions in displaying trustworthiness, which plays a crucial role in cheater detection. Participants ( = 30 and 28 in Experiments 1 and 2, respectively) observed facial photographs of cheaters and cooperators in an economic game and evaluated their facial expressions in terms of emotional valence and arousal. The models in the photographs had turned their left or right cheek to the camera to display their trustworthiness in the economic game. The results indicated that cheaters showing their left cheek were rated as more emotionally positive than cheaters showing their right cheek. This lateral difference was not observed for cooperators. A left cheek advantage in emotional arousal was found for both cheaters and cooperators. These results suggest that cheaters use a fake smile on the emotional side of their face (i.e., the left) to conceal their uncooperative attitude.
欺骗检测是社会合作进化的前提，已在实验室环境中成功模拟。然而，这个过程并不完美，因为检测率通常仅略高于机会水平。本研究调查了侧摆姿势偏见和情绪表达在显示可信度方面的作用，而可信度在欺骗检测中起着关键作用。参与者（实验 1 和实验 2 中分别为 30 人和 28 人）观察了经济游戏中欺骗者和合作者的面部照片，并根据情绪效价和唤醒度评估了他们的面部表情。照片中的模特向左或右脸颊转向相机，以显示他们在经济游戏中的可信度。结果表明，与展示右脸颊的欺骗者相比，展示左脸颊的欺骗者被评为更积极的情绪。对于合作者来说，没有观察到这种侧面差异。欺骗者和合作者的情绪唤醒都表现出左侧优势。这些结果表明，欺骗者会在脸部的情绪侧（即左侧）使用虚假的微笑来掩饰他们不合作的态度。
