The effects of facial expressions on gaze-triggered attention without awareness

他者の視線の方向へと注意が捕捉される効果は，手がかりが閾下呈示された場合にも生じることが報告されている．また，視線注意効果が恐怖表情によって影響を受けることも知られている．本研究は，表情による視線注意効果への影響が，刺激に対する意識的気づきがない場合でも生じるかどうかを検討した．視線を手がかりに用いた空間的手がかり課題において，恐怖表情と中性表情の視線を17 msという短時間呈示することで，刺激に対する意識的気づきを操作し，注意効果が生じるかどうかを調べた．実験1では，恐怖表情と中性表情で同程度の視線注意効果が生じ，表情の効果はなかった．これは用いたマスク刺激が参加者に，顔が呈示されているという構えを生じさせたためであったと考え，刺激を変えて実験2を行った．その結果，恐怖表情と中性表情とで視線による注意効果は異なり，視線による注意効果への表情の影響は，意識的気づきを必要としない自動的な過程によって生じることが示された．The gaze of another individual triggers a reflexive attentional shift. The effect occurs even when gaze cues are presented subliminally. Moreover, gaze-directed attention is influenced by fearful faces. The present study investigates whether facial expression influences gaze-triggered attention when gaze cues are presented subliminally. Photographs of fearful or neutral faces with their gaze directed to the left or the right were presented for 17 ms at the center of the visual field followed by a masking stimulus. A target then appeared unpredictably on the left or the right. The participants' task was to localize the target as soon as possible. The results of Experiment 1 indicate that the effect of facial expression on gaze-triggered attention was not significant, possibly because the masking stimuli established a cognitive set toward face processing in the participants. The results of Experiment 2 using different cues and masking stimuli indicate that reaction times were significantly shorter when a fearful gaze was directed towards the location of the target, whereas this effect was not found for a neutral gaze. These findings indicate that facial expression influences gaze-triggered attention without awareness