The pupillary response as an indicator of fatigue : a study of task-induced effects

Abstract

Previous studies of cognitive fatigue which have used the pupillary response have centered on long term, time-induced effects. Results have indicated that pupil diameter decreases as a function of cognitive fatigue. This study examined the effects of short term, task-induced fatigue on the pupillary response.The research design involved the use of a pre/post paradigm with an interpolated mental multiplication task designed to produce cognitive fatigue. Pupil diameter and rating scale measures were obtained, as well as a measure of the subjects' numerical aptitude. By analyzing the pre/post differences in pupil diameter over time, the use of the pupillary response for the assessment of short term, task-induced cognitive fatigue was demonstrated to be feasible.