Effects of the duration of expressions on the recognition of microexpressions.

Objective: The purpose of this study was to investigate the effects of the duration of expressions on the recognition of microexpressions, which are closely related to deception.

Methods: In two experiments, participants were briefly (from 20 to 300 ms) shown one of six basic expressions and then were asked to identify the expression.

Results: The results showed that the participants' performance in recognition of microexpressions increased with the duration of the expressions, reaching a turning point at 200 ms before levelling off.