Comment by orwin

Although it's not completely pseudoscience, in a sense that microexpressions do exist. You can't detect most of them with your bare eyes, and those you can detect (pupil dilatation) are not significative and can be caused by external factors. I heard in a skeptic podcast that the "ripple under the eyes" in case of a true smile is not fake though, its one of the few thing they got right (not the first time a pseudoscience got some part right, but this time it not just lucky).