关键词: 注视方向, 注意, 动态变化, FPVS, ssVEP

Abstract: As a non-verbal cue, the gaze direction plays an important role in interpersonal communication. Previous studies found that the information obtained from the direct gaze are processed faster and more accurate than that of averted gaze, which is called the advantage of direct gaze. So far, the mechanism of this phenomenon is still under debating. A considerable number of behavioral studies have been conducted to discuss this issue. Some of them found that direct gaze attracts more attention, on the contrary, others reported that direct gaze induced a higher arousal level. In addition, and the results of EEG studies also provide evidence for this issue, supporting the view that direct gaze is more attractive than averted gaze. However, the interaction of the low-level feature and high-level social information affects the results. In conclusion, whether the direct gaze attracts more attention, and whether the advantage is resulted from more significant social information with the direct gaze, are still debating. It is possible that the use of static stimulus and visual search paradigm in previous studies caused the contrary results. Using EEG technology, the present study adopted fast periodic visual stimulation paradigm (FPVS) to achieve dynamic visualization of gaze direction, with the ssVEP as the indictor. We conducted 3 serial experiments to investigate whether dynamic direct gaze captures more attention, and what are the key factors of influence the direct gaze capturing attention, The results are showed as follows. In the experiment 1, the SNR of ssVEP for A-D was higher than that for D-A under the upright face condition, however, no significant difference under the inversed face condition. These results suggest that direct gaze attracts more attention than averted gaze, and the effect results from the high-level social information rather than the low-level feature information. In the experiment 2, no significant difference in amplitude and SNR of ssVEP between direct gaze and averted gaze was found when the static images were presented indicating that the dynamic change of gaze direction is the key factor for direct gaze capture attention. In the experiment 3, after the variation amplitude of the dynamic gaze direction is reduced, no significant difference in amplitude and SNR of ssVEP between direct gaze and averted gaze was found as well, indicating that the variation amplitude of gaze direction is the key factor for the direct gaze to capture attention. Only when the variation amplitude of gaze direction is large, the direct gaze is more attractive than averted gaze. The findings of this study reveal that dynamic direct gaze attracts more attention than averted gaze, and the advantage of direct gaze in capturing attention is due to its special social significance. Furthermore, the dynamic presentation of gaze direction and large amplitude of variation are the key factors for the advantage of direct gaze in capturing attention.

Key words: gaze direction, attention, dynamic change, FPVS, ssVEP