48 two-person teams communicated through channels simulating various modes of telecommunication, teletypewriter, telephone, and closed-circuit television, and, as a control, face-to-face conversation. Each team was required to solve one of four problems. Two cooperative problems, a class scheduling and a geographic orientation problem, required the mutual exchange of factual information to reach the unique problem solution. Two conflictive problems, an issue ranking and a budget negotiation problem, were formulated to engender contention between the two team members. Performance was assessed on three classes of dependent measures: time to solution, behavioral measures of activity, and measures of verbal productivity. Additionally, the protocols and outcomes of the conflictive problem-solving sessions were examined to arrive at a measure of the degree of persuasion exhibited by the two communicators. For both kinds of problem solving, there was a sharp dichotomy in performance, on all three classes of dependent variable, between the teletypewriter mode and the other three modes all of which had a voice channel. Solutions to all problems in the voice modes were much faster but at the same time far more verbose than those in the teletypewriter mode. The addition of a visual channel to a voice mode does not appreciably decrease solution times, nor does it matter whether the visual channel is “live,” that is, face-to-face, or mediated by a closed-circuit television system. For the most part, mode effects were robust and held for all problems. The characteristics of the several modes of communication were largely independent of the kind of task assigned to the teams of subjects.
