Micro expressions are involuntary fleeting expressions of emotion which sometimes last as short as 1/125th of a second. With the popularity of the TV series “Lie to Me” they’ve become all the rage, with people thinking they can use them to detect whether or not people are lying.

Its not helped that on the show, characters exclaim “he’s lying” at the first sign of a micro-expression.

Its also not helping that you read articles stating that micro-expressions in and of themselves are signs of lying. They’re not.

If someone is happy they generally show an expression of happiness. If someone is happy but doesn’t want to show that for some reason, we might see what’s called a micro expression of happiness. That doesn’t mean the person is lying because there are all sorts of reasons why someone my not want to show their happiness. Indeed we don’t even know what might have been going through the person’s head when that fleeting expression happened.

If you watch “Lie to Me” more than superficially its actually not a bad representation of Ekman’s theories. Its about looking for micro expressions which are out of place. They ask different questions to try and find out what the micro expression they saw is about. They don’t just leap to a conclusion the person is lying – though this is what is unfortunately coming across to some people watching the show.

Micro expressions are fleeting facial expressions that occur when some people try to repress or suppress an emotion. If they are unable to do so completely, the emotion may flash onto the face very rapidly, sometimes for as short a time as 1/125th of a second. Although most of us miss most of these fleeting expressions, about 85% of people can improve their micro expression recognition ability with training. (http://www.paulekman.com/mett.html)