Key points are not available for this paper at this time.
Pictures of human faces posing six distinct emotions (plus a neutral expression) and their mirror reversals were split down the midlines, and left-side and right-side composites were constructed. Subjects judged left-side composites as expressing emotions more intensely than right-side composites. The finding indicates hemispheric asymmetry in the control over emotional expression in the face.
Sackeïm et al. (Fri,) studied this question.