Abstract
The author conducted a laboratory experiment to estimate the mental workload of subjects as they acquired visual and auditory information. The following factors were examined using a within-subjects design experiment.
•Presentation method: The 3 modes of presenting both auditory and visual information simultaneously, presenting only auditory information, and presenting only visual information;
•Whether information was recalled vocally or silently after it was presented; and
•Three time periods for analysis: before, during, and after presentation.
As a subsidiary task, subjects were made to rotate a mounted disk 6cm in diameter one full turn every 2s. The variance in time to rotate the disk was examined to clarify the differences in mental workload between experimental conditions. The results were as follows. No difference in mental workload was found among the 3 presentation modes. Moreover, it was clearly shown that mental workload was highest when subjects replied vocally.
