Abstract
This study investigated how the format of verbal instructions in computer simulations and prior knowledge (PK) affected 8th graders' cognitive load (CL) level and achievement in a multimedia learning environment. Although PK was not found to significantly affect student performance and CL level, instruction format was found to impact both. Students who used narrative simulations were found to have a greater CL but also to perform better than those using simulations with on-screen text instructions. However, no significant differences were found between the cognitive efficiency of the two groups. The difficulty of the subject matter and limitations in students' prior content-related knowledge may have increased the intrinsic CL, such that students had difficulty in interpreting the content even if their PK was relatively high. The narrative instructions were more likely than the on-screen text information to reduce the extraneous CL and promote understanding of content. A new measure of cognitive processing is needed to identify the types of CL involved in e-learning and determine the properties of adequate e-learning materials. Finally, the findings of the study are discussed and suggestions for future studies and instructional design are provided.
Acknowledgements
The authors would like to acknowledge the contributions of Chemical Education Research Group at Iowa State University led by Dr. Thomas Greenbowe who granted us the permission to use the simulations in this study. This research project was supported in part by the National Science Council, Taiwan; Grant no: NSC-96-2520-S-415-003.