Improved intertask coordination after extensive dual-task practice

Abstract

This study examines whether an improved intertask coordination skill is acquired during extensive dual-task training and whether it can be transferred to a new dual-task situation. Participants practised a visual–manual task and an auditory–vocal task. These tasks were trained in two groups matched in dual-task performance measures before practice: a single-task practice group and a hybrid practice group (including single-task and dual-task practice). After practice, the single-task practice group was transferred to the same dual-task situation as that for the hybrid practice group (Experiment 1), both groups were transferred to a dual-task situation with a new visual task (Experiment 2), and both groups were transferred to a dual-task situation with a new auditory task matched in task difficulty (Experiment 3). The results show a dual-task performance advantage in the hybrid practice group over the single-task practice group in the practised dual-task situation (Experiment 1), the manipulated visual-task situation (Experiment 2), and the manipulated auditory-task situation (Experiment 3). In all experiments, the dual-task performance advantage was consistently found for the auditory task only. These findings suggest that extended dual-task practice improves the skill to coordinate two tasks, which may be defined as an accelerated switching operation between both tasks. This skill is relatively robust against changes of the component visual and auditory tasks. We discuss how the finding of task coordination could be integrated in present models of dual-task research.

Keywords:

• Dual task
• Practice
• Learning
• Intertask coordination

Acknowledgments

The present research was supported by grants from the German Research Foundation to T.S. and P.F. (DFG Schu 1397/3–2; 5–1). The work was part of the dissertations of the two first authors supervised by T.S. (last author); both authors contributed equally, and order of authorship was decided alphabetically.

Notes

¹ However, as the given group sizes are relatively small, the lacking difference in the VM task between the two groups could be due to a lack of power, as was suggested by one anonymous reviewer. Therefore, one could argue that an increase of the group size might have revealed latent differences between the two groups. In order to test that, we performed an additional power analysis, which demonstrated that the finding of comparable VM task performance in both groups was quite robust. Given α, power, and the effect size of the present experiment, the group factor and the interaction of group and trial type would still not reach a significant value if we were to double the number of participants in both groups (G*Power: Faul, Erdfelder, Buchner, & Lang, 2009).