The effect of redundant text in multimedia instruction

The purpose of this study was to examine the redundancy effects obtained when spoken information was duplicated in writing during the learning of a multimedia document. Documents consisting of diagrams and spoken information on the development of memory models were presented to three groups of students. In the first group, no written text was presented. In the second, written sentences redundant with the spoken information were progressively presented on the screen while in the third group, these written sentences were presented together. The results show that whatever the type of text presentation (sequential or static), the duplication of information in the written mode led to a substantial impairment in subsequent retention and transfer tests as well as in a task in which the memorization of diagrams was evaluated. This last result supports the hypothesis that the visual channel is overloaded as the cognitive theory of multimedia learning suggests.