Using eye movement activity as a correlate of cognitive workload

In the present study, we investigated the effect on air traffic controller operations and workload from the use of weather displays. Specifically, we assessed the impact on severe weather avoidance, controller efficiency, controller-pilot communications, and the safety of airspace operations when controllers managed traffic during adverse weather conditions. The results showed a significant impact on controller efficiency from the use of weather displays with an increase in sector throughput by up to 10%. We found no significant effects of weather displays on severe weather avoidance, controller communications, and subjective workload ratings. However, using eye movement activity measures that correlate with cognitive workload, we found significantly shorter blink durations when controllers operated traffic in conditions lacking a weather display, indicating a higher workload level during these conditions. Also, the mean pupil diameter was significantly larger when controllers used a static storm forecast tool compared to when controllers used a dynamic forecast tool, indicating a higher workload level during the use of static tools. We conclude that eye movement activity measures can provide a more sensitive measure of controller workload, and that subjective ratings might not capture more transient fluctuations in workload levels during system or display interactions.Relevance to industryUsing real-time eye movement activity measures, designers can better evaluate changes in operator workload during the design and evaluation of complex systems. If we can detect workload-inducing conditions early in the design process, we can improve the design, optimize operator workload, and reduce developmental costs.