Estimating Mental Workload of University Students using Eye Parameters

Abstract

Estimating mental workload using eye parameters in different fields has become a significant study focus in the area of research. It is vital to discover the most reliable eye parameter/parameters that can be used to estimate mental workload. In this study, N-back tasks with four difficulty levels were designed to induce mental workload for a sample of 21 university students at NTNU Gjøvik. 17 eye parameters were measured using SMI RED250mobile Eye Tracker at a sampling rate of 250 Hz. Analyzed data indicate that peak fixation duration is the most suitable eye parameter to estimate mental workload. It has a negative relationship with the mental workload, where higher peak fixation duration can be observed at lower mental workload and lower peak fixation duration at higher mental workload. Moreover, blink frequency, blink count, peak blink duration, and pupil diameter show a significant positive relationship to the mental workload. Most of the saccade parameters failed to show a significant relationship, while fixation frequency, fixation duration, fixation count, blink duration, saccade velocity, and peak saccade amplitude showed a partial relationship with the mental workload.