How do face processing strategies and eye-movements contribute to individual differences in face recognition ability?

The present study aimed to investigate the contribution of holistic processing and eye-movements in explaining individual differences in face recognition (FR). Participants completed the Cambridge Face Memory Test-Long Form (CFMT +) to evaluate their FR-ability along with a face recognition task in which the inversion method was employed to hinder holistic processing while their eye-movements were recorded. We implemented two different analysis strategies on the behavioral and eye-movement data, testing i., the moderator role of CFMT + scores on the inversion effect and ii., the association between CFMT + scores and inversion indexes calculated based on the residual method. Importantly, both strategies converged on the same result: participants with higher FR-ability used holistic strategy more than those with lower ability. Moreover, they tended to make longer fixations to the eye region of the upright faces than inverted ones, and this inversion effect on fixation duration becomes larger as participants' FR-ability increase. Yet, these effects explain only a small portion of the variance in FR-ability. We conclude that holistic processing and eye-movements partially contribute to individual differences in FR-ability relying on heterogeneous perceptual and cognitive mechanisms.