ABSTRACT
As discussed in this chapter, the study of multitasking examines how well each task in a task set is performed in combination, relative to how each is performed alone. If there is a decrease in performance, it is described as a dual-task decrement, and the mechanisms by which this decrement is produced is examined in this chapter. Multitasking requires the division of attention between tasks, rather than between information channels, as discussed previously. This chapter provides a theoretical framework to aid people in their understanding of what causes multitasking decrements. The chapter focuses on five general mechanisms to aid engineering psychologists: relative effort, demand similarity, task priority, task strategy, and information similarity. Sometimes tasks are performed concurrently and sometimes sequentially through discrete task switching, with different theories, models, and principles underlying each to predict the full range of multitasking performance. This chapter provides a comprehensive review of multitasking and time-sharing utilizing the concepts from multiple resource theory and switching theories. The chapter concludes with a focus on multitasking in the vehicle.
