A coherence effect in multimedia learning: The case for minimizing irrelevant sounds in the design of multimedia instructional messages

The authors tested the recommendation that adding bells and whistles (in th e form of background music and/or sounds) would improve the quality of a mu ltimedia instructional message. In 2 studies, students received an animatio n and concurrent narration intended to explain the formation of lightning ( Experiment 1) or the operation of hydraulic braking systems (Experiment 2). For some students, the authors added background music (Group NM), sounds ( Group NS), both (Group NSM), or neither (Group N). On tests of retention an d transfer, Group NSM performed worse than Group N; groups receiving music performed worse than groups not receiving music; and groups receiving sound s performed worse (only in Experiment 2) than groups not receiving sounds. Results were consistent with the idea that auditory adjuncts can overload t he learner's auditory working memory, as predicted by a cognitive theory of multimedia learning.