Individual differences in baseline eye movement indices: Examining the relationships between baseline pupil size, inhibitory control, and fixation stability

The relationship among baseline pupil size, fixation stability, and inhibitory control were examined in this study. Participants performed a baseline eye measure in which they were instructed to stare at a fixation dot on screen for 2 min. Following the baseline eye measure, participants completed an antisaccade task to measure inhibitory control ability. We found a correlation between baseline pupil size variability and inhibitory control, as well as between fixation stability and inhibitory control. We showed that participants with better inhibitory control exhibited larger variability in pupil size, and those with better fixation stability showed superior inhibitory control ability. Overall, our results indicate that there are significant correlations between inhibitory control and baseline pupil size, as well as between inhibitory control and fixation stability.