People are accurate at classifying emotions from facial expressions but much poorer at determining if such expressions are spontaneously felt or deliberately posed. We explored if the method used by senders to produce an expression influences the decoder’s ability to discriminate authenticity, drawing inspiration from two well-known acting techniques: the Stanislavski (internal) and Mimic method (external). We compared spontaneous surprise expressions in response to a jack-in-the-box (genuine condition), to posed displays of senders who either focused on their past affective state (internal condition) or the outward expression (external condition). Although decoders performed better than chance at discriminating the authenticity of all expressions, their accuracy was lower in classifying external surprise compared to internal surprise. Decoders also found it harder to discriminate external surprise from spontaneous surprise and were less confident in their decisions, perceiving these to be similarly intense but less genuine-looking. The findings suggest that senders are capable of voluntarily producing genuine-looking expressions of emotions with minimal effort, especially by mimicking a genuine expression. Implications for research on emotion recognition are discussed.

人们能够准确地根据面部表情对情绪进行分类，但是很难确定是否是自发感觉到或故意摆出了这种表情。我们探索了发件人用来生成表达式的方法是否会影响解码器区分真实性的能力，并从两种著名的代理技术（Stanislavski（内部）和Mimic方法（外部））中汲取了灵感。我们比较了自发的惊喜表达，以应对“千斤顶”（真正的条件）与摆姿势的发件人的展示，这些发件人要么专注于过去的情感状态（内部条件），要么专注于向外的表达（外部条件）。尽管解码器在区分所有表达式的真实性方面表现胜于偶然，但与内部意外事件相比，在对外部意外事件进行分类时其准确性较低。解码器还发现很难将外部惊喜与自发惊喜区分开，并且对他们的决定没有信心，他们认为这些同样强烈但看上去不太真实。这些发现表明，发件人能够以最小的努力，特别是通过模仿真实表情来自愿产生真实表情的情绪表情。讨论了对情绪识别研究的意义。