Asymmetry in emotional face: its role in intensity of expression.

Normal subjects rated expressiveness of two posed facial emotions, happy and sad; the photographs were stratified in terms of intensity of expression and were prepared in composite (right-right, left-left), normal, and mirror-reversed facial orientations. The left side of the face was more expressive for intermediate intensity expressions of happiness and for least intense expressions of happiness and sadness. The right side of the face was more expressive for most intense expressions of happiness and sadness.