Joan C. Borod Elissa Koff Marjorie Perlman Lorch Marjorie Nicholas
Everyday experience and scientific study suggest that the face is a primary organ for communication of emotional expression. It is well known that among the animals, the human being has the most extensively developed facial musculature and is heavily dependent on facial behavior to facilitate social interaction ( Roberts, 1966) and emotional communication ( LoCastro, 1972; Mehrabian & Wiener, 1967). Much attention has focused recently upon the neuropsychological mechanisms involved in the facial expression of emotion ( Borod & Koff, 1984; Rinn, 1984). While the majority of studies in this area have used normal adult subjects, investigators recently have begun to examine facial behaviors in brain-damaged populations. Studies of facial emotion in patients with unilateral focal brain damage provide an opportunity to illuminate brain/behavior relationships underlying the emotional processing system in the human being. In this chapter, we describe our program of research which has investigated multiple aspects of emotional facial expression in a group of focal lesion patients with fight or left hemisphere pathology and in normal matched controls ( Borod & Koff, 1982; Borod, Koff, & Buck, in press; Borod, Koff, Perlman [Lorch], & Nicholas, 1983, 1984, 1985, in press; Perlman, Borod, Nicholas, & Koff, 1984).
A special role for the right hemisphere has been recently suggested for both the perception and expression of facial emotion (for review, see Borod, Koff, & Caron, 1983). In normals, perception studies have demonstrated left visual-field (i.e., right hemisphere) advantages for perceiving emotional expression ( Hansch & Pirozzolo, 1980; Ley & Bryden, 1979; McKeever & Dixon, 1981; Strauss & Moscovitch, 1981; Suberi & McKeever, 1977). Expression studies have docu-