Task priority reduces an adverse effect of task load on automation trust in a dynamic multitasking environment.

The present study examined how task priority influences operators' scanning patterns and trust ratings toward imperfect automation. Previous research demonstrated that participants display lower trust and fixate less frequently toward a visual display for the secondary task assisted with imperfect automation when the primary task demanded more attention. One account for this phenomenon is that the increased primary task demand induced the participants to prioritize the primary task than the secondary task. The present study asked participants to perform a tracking task, system monitoring task, and resource management task simultaneously using the Multi-Attribute Task Battery (MATB) II. Automation assisted the system monitoring task with 70% reliability. Task load was manipulated via difficulty of the tracking task. Participants were explicitly instructed to either prioritize the tracking task over all other tasks (tracking priority condition) or reduce tracking performance (equal priority condition). The results demonstrate the effects of task load on attention distribution, task performance and trust ratings. Furthermore, participants under the equal priority condition reported lower performance-based trust when the tracking task required more frequent manual input (tracking condition), while no effect of task load was observed under the tracking priority condition. Task priority can modulate automation trust by eliminating the adverse effect of task load in a dynamic multitasking environment. [ABSTRACT FROM AUTHOR]