29. Multiple-Channel Communications: The Theoretical and Research Foundations of Multimedia

David M. (Mike) Moore

Virginia Polytechnic Institute and State University

John K. Burton

Virginia Polytechnic Institute and State University

Robert J. Myers

Wheeling Jesuit College

29.1 Introduction*

The ability of technology to make information available quickly and provide an individualized learning opportunity has long been discussed and dreamed of. These desires go back to Pressey's teaching machines of the 1920s and Bush's theoretical "Memex" information retrieval system of the 1940s. Since the beginning of the microcomputer computer revolution in the late 1970s, however, the dream has become a reality. Proponents have extolled the virtues of instruction supported, assisted, or conducted by the computer (e.g., Papert, 1977; Suppes, 1980). Others have exercised less enthusiasm about the effects of any media per se. Clark (1983), for example, said that mediated environments are merely sufficient, not necessary, for the learning process. Teachers, as practitioners, will ultimately decide whether incorporation of new technologies into the classroom is worth the time and effort (Moore, Myers & Burton, 1994).

This chapter focuses on the theories and effects related to multiple-channel communication, which undergirds notions of multimedia instruction. Because cognitive notions of learning currently have widespread acceptance, we will use them as the perspective for the review. Specifically, we will use the information-processing view of the cognitive system because it, like current views of multimedia itself, relies so heavily on the computer. The informationprocessing approach focuses on how the human memory system acquires, encodes, retrieves, and uses information. This approach applies information theory and computer analogies to human learning. Within the informationprocessing model, topics and research reviewed incldde multiple-channel communication, including modalities of instruction, cue summation and stimulus generalization, channel interference, and capacity. We, however, resisted the temptation to include and thus report on cueing strategies and other remotely related theories. Related research literature in areas of multi-image and subliminal perception are also investigated and summarized.

The term multimedia has been used for a long time by educators as well as those in the technology industry, yet there is little consensus as to what, exactly, the concept includes (Strommen & Ravelle, 1990). Until recently, the term has meant the use of several media devices in a coordinated fashion (e.g., synchronized slides with audiotape). Advances in technology, however, have combined these media so that information previously delivered by several devices is now integrated into one device (Kozma, 1987, 1991). Obviously the computer plays a central organizing role in this environment, and just as obviously the computer allows interactivity and, constrained only by the size of the lesson, unlimited branching. Because of this history, many authors (see, for example, Matchett & Elliot, 1991) argue that multimedia should encompass interactive systems. This allows the notion of multimedia not only to accommodate interactive video, for example, but also to absorb the historically older concept of hypermedia (Moore, Myers & Burton, 1994). In part because we don't agree (we tend to see multimedia as a special case of hypermedia with one, linear path specified), and in part because of the more practical reason that such things as interactive video, etc., are covered elsewhere in this handbook, we will limit our definition, and hence our coverage, to systems that include two or more of the following: motion, voice, data, text, graphics, and still images.

Multimedia research is evaluated with the intent of answering the question: Does multimedia really work? Speculation on multimedia message design based on past and current research concludes this chapter.

*The authors appreciate the research assistance of James A. DeChenne, Helen B. Miller, John E Moore, and Joanne B. Whitley.