Integrating Psychophysiological Measures of Cognitive Workload and Eye Movements to Detect Strategy Shifts

This paper presents a case study to introduce a new technique for identifying and comparing cognitive strategies. The technique integrates eye movements with the Index of Cognitive Activity, a psychophysiological measurement of cognitive workload derived from changes in pupil dilation. The first part of the paper describes the technique and its constituent elements. The second part describes the task used in this study. The task has been used extensively in previous studies with electrophysiological recordings of EEG, EOG, and EMG and is know to elicit different levels of cognitive workload. The third part of the paper shows the results and provides detail about three separate strategies that emerged in the subject’s performance. The strategies are first identified from differences in the Index of Cognitive Activity and corroborated through detailed analyses of the participant’s eye movements as he performed the task.