How can we help students to understand scientific explanations of cause-and-effect systems, such as how a pump works, how the human respiratory system works, or how lightning storms develop? One promising approach involves multimedia presentation of explanations in visual and verbal formats, such as presenting computer-generated animations synchronized with computer-generated narration or presenting illustrations next to corresponding text. In a review of eight studies concerning whether multimedia instruction is effective, there wz~s consistent evidence for a multimedia effect: Students who received coordinated presentation of explanatio:ns in verbal and visual format (multiple representation group) generated a meldian of over 75% more creative solutions on problem-solving transfer tests than did students who received verbal explanations alone (single representation group). In a review of 10 studies; concerning when multimedia instruction is effective, there was consistent evidence for a contiguity effect: Students generated a median. of over 50% more creative solutions to transfer prolblems when verbal and visual explanations were coordinated (integrated group) than when they were not colordinated (separated group). Finally, in a review of six studies concerning for whom multimedia instruction is effective, Attribute x Treatment interactions indicated that multimedia and contiguity effects were strongest for low prior knowledge and high spatial ability students. Results are consistent with a generative theory of multimedia learning in which learners actively select, organize, and integrate verbal and visual information. For the past 7 years, my colleagues and I at the University of California, Santa Barbara, have been examining methods for improving students' understanding of scientific explanations. Here's the kind of situation that got us interiested. I ask a student who lacks experience in meteorology to read a short text lesson explaining how lightning storms develop. The passage contains approximately 600 words and includes a cause-and-effect explanation of the events lieading to the formation of lightning. A few minutes later, I ask the student to answer a transfer question, that is, a question that requires reasoning about the information in the lesson. In spite of an earnest attempt to learn, he or she is unable to produce an acceptable answer and, in fact, performs no better than an equivalent student who has not received any training. Why is it that a student can read or listen to every word of a scientific passage, including a cause-and-effect explanation, and yet not be able to use that information to solve problems? Our research has produced convincing evidence that presenting a verbal explanation of how a system works does not insure that students wnll understand the explanation. In our search for ways to help students understand scientific explanations, we have come to rely increasingly on what has been Requests for reprints should be sent to Richard E. Mayer,
Mayer defines multimedia as the presentation of material using both words and pictures, and proposes that presenting verbal explanations alone in instructional situations is less conducive to learning for some students than presenting verbal explanations in conjunction with pictures REF .
Multimedia learning: Are we asking the right questions?
Educational Psychologist
Psychology