今天中午吃完飯之後看了一集《Lie to me》，裡面有這麼一段話：

When a person’s facial expression is not symmetrical across their face, it is likely that they are pretending to feel the emotion.

我去查證了一下是不是真的有學者提出這樣的看法，我查到有篇文章介紹Paul Ekman所提出的理論，裡面寫到：

(略)… spontaneous expressions tend to always be more symmetrical – with both sides of the face being more equally effected. When a facetious expression is made voluntarily, this symmetry is always less obvious. Thus,a crooked expression where the sides of the face are mismatched, is a reliable indication that the expression is not genuine but is being voluntarily created.

請看活生生血淋淋的例子：

(取自馬英九：「風雨會過去，大家要有信心。」)

馬總統的這種臉部不對稱表情應該不是天生的吧 ……