Abstract
Recent face perception studies have explored individual differences with regard to visual processing strategies. Two main strategies, associated with distinct eye movement patterns, have been highlighted: global (or holistic) face processing involves fixations near the center of the face to facilitate simultaneous peripheral processing of key facial features (i.e. eyes and mouth); local (or analytic) face processing involves fixations directed to those facial features (Chuk et al, 2014; Miellet et al, 2011). Since it has been shown that peripheral processing entails lower spatial resolution (Goto et al, 2001), global face processing may theoretically be linked to lower spatial frequency (SF) sampling. By contrast, local face processing may allow the extraction of higher SFs. However, the link between eye movements and SF extraction has not yet been empirically verified for face recognition. Thus, the current study proposes to investigate this question. The eye movements of 21 Canadian participants were monitored while they completed an Old/New face recognition task. Subsequently, the SF Bubbles method (Willenbockel et al., 2010) was used to measure the same participants’ SF utilization during a face identification task. Fixation duration maps were computed for each participant using the iMap4 toolbox (Lao et al., 2017), and participants’ individual SF tuning peaks, obtained with SF Bubbles, were calculated. In line with previous studies, our participants’ initial fixations generally landed near the center of the face, with varying degrees of proximity to this location (Euclidean distances: from 25.76 to 146.03 pixels; SD of 32.08 pixels). Crucially, SF peaks significantly correlated with the location of the first fixation (r = −0.46; p = 0.037): participants using higher SFs initially gazed closer to the left eye than participants using lower SFs. These results suggest that greater reliance on high SFs is associated with early fixations toward the left eye region.
Acknowledgement: Natural Sciences and Engineering Research Council of Canada