You have 80 muscles that control what happens on your face. Those muscles communicate at least 40 different groups of expressions-the six primary emotions and their blends. Actors study expressions to seem more realistic. Police detectives look at the faces of suspects and witnesses to help determine if they are telling the truth. Airport security people study faces of travelers to look for clues about danger in the skies.
Medical professionals observe facial reactions during physical exams.
Interpreters closely watch the faces of the speakers to determine accurately the message to translate. Reading faces is an important survival skill. Researchers at the Massachusetts Institute of Technology's Media Lab are working on many projects that involve computers learning to imitate human movement, actions, and even emotions. One project involves developing ways for computer-generated models to interact with each other, using speech with appropriate intonations, hand gestures, and facial movements. In another, scientists use algorithms to generate facial animations from speech and are studying how the face, hands, and speech complement each other in our communication.