ABSTRACT
In natural interactive settings people use a variety of different nonverbal cues to communicate, including voice intonation and quality, facial expression, proximity, and eye contact. Thus Birdwhistell (1961, p. 5) refers to the human as a "regulated multisensory station in a transmission system, a multichannel interactor." The experimental study of those clues, however, has encountered various methodological difficulties, due in part to the inherent problems of studying each communication channel and in part to the complications of multichannel research.
