Effects of synchronous redundancy in multimedia on recognition
This thesis considered whether multimedia learning materials should simultaneously combine continuous text captions, audio, and video. Multiple Resource Theory suggests that interference among media competing for resources may diminish attention and learning. In contrast, redundancy advocates claim that when media present redundant content, learning is not limited by interference and may even be enhanced. These contrasting perspectives were tested by measuring recognition, comprehension, and subjective experience in three groups. One group saw an audio-video (AV) program with redundant text captioning ("in-synch"). A second group saw the same content, but the captions were delayed by 10 seconds. The control group saw only the AV. Results were marginal, but indicated some trends. The "in-synch" group's recognition of audio content was enhanced relative to the control group. They found it easier to pay attention, were more biased to say they recognized audio content-prompts, and tended to be more sensitive (accurate) than the control. In fact, significantly more subjects had a higher sensitivity to audio than video. The group which received "out-of-synch" captions also were more biased, but not more sensitive than the control, and found the captions difficult to follow.