Task performance under influence of interruptions

Abstract. An execution of computerized task was analyzed in simulated office environment 1. Work of subjects in half of the cases was interrupted. Interrupting tasks varied in complexity. The main task was interrupted at different points. It was shown that (1) interruptions decreased accuracy of performance and increased the number of task related actions, but the time spent for the execution of the main task did not change; (2) more complicated interrupting tasks intensify subjects ’ activity, consume more time for the resumption of the main task, but lead to a significant decrease in the number of errors; (3) the more difficult was a subtask in the moment of interruption, the more elaborated behavioral strategies were used in the condition of interference. Results were interpreted in the framework of Leontiev’s Activity Theory. Interruption can be determined as a certain event, which interferes with work process and results in the cessation and suspension of human activity. Brief external interference is often considered as an everyday stressor with negative impact on the effectiveness of performance. Under condition of interruption people look for ways of overcoming its negative influence