text: The computer's also need to understand that most human non communication is non verbal there are muscles called orbicularis oculi pars palpabraeus that makes crow's - feet around your eyes. But when you are not really smiling in a fake smile,the mouth is strecthed sideways using the zygomatic major and a different muscle,the risorius. These muscles clues are sometimes used to spot when a "smiling" politician or celebrity is fake smiling.