Facial displays
Just as there are conversational hand gestures, there are also conversational (non-emotional) facial displays, which convey information related to the topic of the dialogue. Facial displays are typically very fleeting (often less than one to two seconds), so they can be tightly synchronized with words. Both speakers and addressees make frequent facial displays. Speakers illustrate what they are saying as they are saying it, and addressees display their responses to what the speaker is saying without interrupting. Our research shows that these facial displays in face-to-face dialogue do not express inner emotions; rather, they convey meaning to another person.
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