关键词: 面孔-词Stroop范式, 情绪冲突, Stroop 不对称效应, Stroop效应

Abstract: In the face-word Stroop paradigm, a Stroop effect has been observed in the facial expression naming task as well as in the emotional word classification task. Those results suggest that the new emotional Stroop task may fail to show Stroop asymmetry which is a hallmark of the color-word Stroop task. Is the face-word Stroop effect non-analogous to the color-word Stroop effect after all? The purpose of this study is to investigate the interference effect in the face word Stroop task. The Chinese words “愉快 ” (“yukuai”, means happy) or “ 恐惧” (“kongju” means fear) were written in red letters across the faces, resulting in an affective congruent or incongruent matching. The total of 40 stimuli was used. Each picture was presented two times, with duration of 150ms or 1500ms separately, resulting in a block of 80 randomized trials out of which 40 were congruent and the remaining 40 were incongruent. There are four blocks, including two “word task” blocks and two “face task” blocks. The sequence was counterbalanced with an order of ABBA and BAAB. During the interval of two blocks, the participant could have a short break. All of them completed 320 trials in four blocks. All trials were presented in randomized order for each participant. Each trial began with the presentation of a fixation for 400ms. After a random inter stimulus interval (ISI) between 400 and 600 ms, the targets appeared in the center with duration of 150ms or 1500ms. The participant should respond as quickly and accurately as possible once the “?” appeared in the center. With a varying ISI of 1800–2300ms, the next trial began. E-prime software package was used for the stimulus presentation and data acquisition. Reaction times (RTs) and accuracy percentages were analyzed in 2(task: word vs. face) ×2(congruency between face and word: incongruent vs. congruent)×2(stimuli duration: 150ms vs. 1500ms) ANOVAs. For the RTs data, there was significant interaction between congruency and task. The interaction between duration and task was also significant. The main effects of these three factors were all significant. Further analysis indicated that the RTs in the “word task” was shorter than the “face task” when the targets displayed with a duration of 150ms, but not 1500ms. Furthermore, in the “face task”, when the targets displayed with a duration of 150ms, RTs were shorter for congruent compared to incongruent trials, i.e., a Stroop effect occurred; but in the “word task”, there was no significant difference in RTs between incongruent trials and congruent trials. When the targets displayed with a duration of 1500ms, there was no significant emotional conflict effect in the face task and in the word task. And there were no significant difference in RTs between face task and word task in the condition of 1500ms. To recap briefly, the present study found that there was a Stroop asymmetry effect in the face-word task. Emotional word processing is not affected by emotional face. And the duration of stimuli is an important factor in the face-word Stroop task. The face-word stroop task should be used carefully in the future studies.

Key words: Face-word Stroop task, emotional conflict, Stroop asymmetry effect, Stroop effect