OBJECTIVE:

This study tested the effects of two fundamental forms of distraction, including visual-manual and cognitive-audio distraction, with comparison under both operational and tactical driving. Strategic control remains for future study.

BACKGROUND:

Driving is a complex control task involving operational, tactical, and strategic control. Although operational control, such as lead-car following, has been studied, the influence of in-vehicle distractions on higher levels of control, including tactical and strategic, remains unclear.

METHOD:

Two secondary tasks were designed to independently represent visual-manual and cognitive-audio distractions, based on multiple resource theory. Drivers performed operational vehicle control maneuvers (lead-car following) or tactical control maneuvers (passing) along with the distraction tasks in a driving simulator. Response measures included driving performance and visual behavior.

RESULTS:

Results revealed drivers' ability to accommodate either visual or cognitive distractions in following tasks but not in passing. The simultaneous distraction condition led to the greatest decrement in performance.

CONCLUSION:

Findings support the need to assess the impacts of in-vehicle distraction on different levels of driving control. Future study should investigate driver distraction under strategic control.