FACIAL EXPRESSION IN EMOTION
It is a familiar fact that the facial muscles are involved in many emotional reactions. Traditionally, the resulting facial expressions have been referred to as "expressions" of emotion, as though to imply that the emotion itself were an inner process perhaps purely "mental" in nature. But to many psychologists today an emotion is quite as much "physical," i.e., physiological, as it is "mental." Facial reactions, gestures, and other observable responses are to them not "expressions" of emotion; rather they are component parts of the emotional pattern itself. However, the problem to be dealt with in this chapter is neither the nature of emotion nor the role which these facial changes play in it. Rather, it is the specific question, Do definite and distinguishable facial patterns characterize the emotional reactions to which we give such names as "fear," "pity," " anger," "disgust," "relief," and so on?
It is a popular belief of long standing that each type of emotional disturbance involves a facial expression which is not only relatively invariable in a given individual, but also is more or less constant throughout the species; that there is, for example, a particular facial expression which is characteristic of fear in almost all individuals and another, and different, expression which is characteristic of anger. Our problem is now to determine whether there are grounds for such a view.
Many studies have been made of the ability of observers to recognize emotions "registered" by actors in posed photographs or sketches. Very often an observer can name with a considerable degree of accuracy the emotions which these posed pictures were intended to portray. At first glance, this result might seem to indicate that certain facial expressions are usually, if not invariably, associated with certain definite emotions. But it is also possible that these poses represent