“…I therefore have excluded studies that focus on the role of nonverbal communication in determining social impressions (e.g., DePaulo, 1992); on the role of gesture as regulating mechanism through back-channeling or gaze-direction (e.g., Bavelas, Chovil, Coates & Roe, 1995;Dittman & Llewellyn, 1968;Duncan, 1972;Kendon, 1967); and on the contribution to communication by proxemics and paralanguage. (For a review of related educational practices see Woolfolk & Brooks, 1983.) I also have excluded studies that focus primarily on development of sign language, influence of neurological damage, speech disfluency, or evolution of language (Gibson & Ingold, 1993;Iverson & Goldin-Meadow, 1998;Messing & Campbell, 1999).…”