Evaluating mental workload while interacting with computer-generated artificial environments
The need to evaluate user behaviour and cognitive efforts when interacting with complex simulations plays a crucial role in many information and communications technologies. The aim of this paper is to propose the use of eye-related measures as indices of mental workload in complex tasks. An experiment was conducted using the FireChief microworld in which user mental workload was manipulated by changing the interaction strategy required to perform a common task. There were significant effects of the attentional state of users on visual scanning behavior. Longer fixations were found for the more demanding strategy, slower saccades were found as the time-on-task increased, and pupil diameter decreased when an environmental change was introduced. Questionnaire and performance data converged with the psychophysiological ones. These results provide additional empirical support for the ability of some eye-related indices to discriminate variations in the attentional state of the user in visualdynamic complex tasks and show their potential diagnostic capacity in the field of applied ergonomics.
microworld task complexity cognitive load mental fatigue saccadic peak velocity eye-movements