The Attentional Costs of Interrupting Task Performance at Various Stages

The visual occlusion technique has received considerable attention in recent years as a method for measuring the interruptible aspects of in-vehicle information system (IVIS) task performance. Because the visual occlusion technique lacks a loading task during “occluded” periods, an alternate method was adopted to provide increased sensitivity to the attentional costs of interruptions on IVIS-style task performance. Participants alternated between performing a VCR programming task and a simple trackmg task. Results indicate that it does matter at which point the VCR task is interrupted in terms of time to resume the VCR task. Specifically, the resumption time, or lag, was lowest right before beginning a new task stage such as entering the show endtime, or when performing a repetitive scrolling task. The results suggest that it might be appropriate to include measures of resumption lag when testing the interruptability of IVIS-style tasks.