Anticipatory and control processes in the interaction with secondary tasks while driving

The paper describes an experiment where anticipatory processes in the interaction with secondary tasks while driving could be explicitly identified and contrasted to control processes during the engagement in the secondary task. A special experimental set-up in a driving simulator environment was created that allows drivers to deliberately decide whether they want to be distracted or not depending on the driving situation and the expected development of that situation. As indicators for a situation-adaptive interaction with secondary tasks parameters from driving behaviour, secondary task performance and visual behaviour were analyzed. A study with 24 test drivers revealed that drivers are, in general, able to interact with a secondary task in a situation-aware manner. For example, drivers rejected more secondary tasks in already highly demanding situations or tried to delay the beginning of the task. During secondary task performance drivers observed the situational development with short control glances back to the road and adapted their speed. The analysis of driving errors revealed that rejecting a task in an already highly demanding driving situation is an effective strategy to maintain an adequate level of driving safety. However, some critical factors were identified that might hinder the driver from executing such strategies. Several recommendations for supporting the driver on this issue are given.