Multiple resources and display formatting: The implications of task integration in a simulated air traffic control task

Two experiments are reported which test the hypothesis that multiple sources of displayed information should be presented to common rather than separate resources when those sources must be integrated with a single mental model of the task. One experiment requires subjects to integrate horizontal and vertical information in a spatially presented air traffic control task. In support of the hypothesis, performance was best when both sources were presented visually, rather than bimodally. In a control experiment when the altitude and horizontal information did not need to be integrated, the performance advantage to intramodel display disappears. In a separate experiment using a digital display of the aircraft position information, no evidence for better processing of the information to be integrated within the visual modality was obtained.