Individual differences in eye movements during face identification reflect observer-specific optimal points of fixation

摘要

Does everybody look at the same place on a face when identifying another person, and if not, does this variability in fixation behavior lead to functional consequences? In one condition, observers’ eye movements were recorded while performing a face identification task. A second condition had the same observers identify faces while their gaze was restricted to specific locations on the face. We found substantial differences which persist in time in where individuals chose to move their eyes. Observers’ systematic departure from a canonical, theoretically optimal fixation point did not correlate with performance degradation. Instead, each individual’s looking preference corresponded to an idiosyncratic performance-maximizing point of fixation: those who looked lower on the face also performed better when forced to fixate the lower part of the face. The results suggest an observer-specific synergy between the face recognition and eye movement systems that optimizes face identification performance.