Eye tracking to investigate information processing demands

When designing a new training system, one of the most important issues to consider is the extent to which the user can interact with the system. Failing to consider the issue of usability can result in a system that impedes, rather than extends performance in the operational environment. Previous approaches to usability testing of training systems have generally been limited to subjective perceptions of the system, the time taken to complete a task, the accuracy of the task, and/or the frequency of errors made. However, these data do not necessarily provide easily interpretable information as to the ease with which a user processes information from the system and the extent to which this process of information acquisition is consistent with the process that occurs within the operational environment. Eye tracking is one method that can be used to establish the usability of the system, both from a behavioural and a cognitive perspective. Specifically, eye tracking data can provide insight into a user’s understanding of a system, in addition to performance in using the system. In the present case, we examined the utility of eye tracking data in establishing the usability of decision support training system. The context was fire fighting, and participants were presented with a list of tasks to perform within the system. Data was recorded regarding the time taken to complete the tasks, the accuracy with which the tasks were performed, the number of times the participants fixated on the interface, and the duration of eye gaze fixations. No statistical differences were found on any of the dependent variables. Therefore, it was concluded that no usability differences exist between the three interfaces.