The document discusses microexpressions, which are brief involuntary facial expressions that reveal emotions. Microexpressions last 1/15 to 1/25 of a second and occur during high-stakes situations. Paul Ekman discovered 7 main detectable microexpressions: happiness, surprise, sadness, fear, anger, disgust, and contempt. Ekman also defined specific action units for different expressions, such as the enjoyment smile involving action units A12 and A6. The document suggests activities for interpreting microexpressions and discusses how understanding microexpressions relates to decoding messages and interpreting paradigms of facial expressions.