When to switch? Understanding how performance tradeoffs shape dual-task strategy
A novel dual-task paradigm was used to investigate how people adapt their task interleaving behavior to meet a specific performance objective. The study required participants to encode and enter a series of route instructions from a secondary display while driving a simulated vehicle. Explicit instructions were given to give greater priority to either safe driving or rapid completion of the secondary navigation task. Results showed that participants met the required task objective by varying the frequency and duration of visits to the secondary task display, and by also varying the amount of time given up to steering control in between visits. We explain these data using a framework for modeling driver distraction effects. The model predicted the observed shift in task performance between the two focus conditions and also the observed change in task interleaving strategy. Taken together these results support the idea that people can strategically control the allocation of attention in multitask settings to meet specific performance criteria.