A Very Innocent Australian Circus Family

A microexpression is a facial expression that only lasts for a short moment.

It is the innate result of a voluntary and an involuntary emotional response occurring simultaneously and conflicting with one another, and occurs when the amygdala responds appropriately to the stimuli that the individual experiences and the individual wishes to conceal this specific emotion.

This results in the individual very briefly displaying their true emotions followed by a false emotional reaction.