面孔-词Stroop范式中的情绪冲突效应研究

Emotional Conflict Effect in the Face-word Stroop Task

为探究面孔-词Stroop范式中的情绪冲突效应,本实验给被试呈现两种时长(150ms或1500ms)的刺激,令其分别完成对面孔-词Stroop范式中的"面孔任务"和"词任务"。结果发现:只有"面孔任务"中出现Stroop效应,产生情绪冲突,而在"词任务"中未出现Stroop效应;当呈现时间为150ms时,情绪词影响情绪面孔加工从而引发个体的情绪冲突,出现Stroop效应;当呈现时间为1500ms时,"面孔任务"中的Stroop效应消失。这提示了呈现时间是影响面孔-词Stroop范式中情绪冲突效应的一个重要因素。

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 Stroopeffect 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 being happy） or ＂恐惧＂（＂kongju＂means being fearful） were written in red letters across the faces,resulting in an affective congruent or incongruent matching. A total of 40 stimuli were used. Each picture was presented two times,with a duration of 150ms or 1500ms,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 had a short break. All of them completed 320 trials in four blocks. All trials were presented in random 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 a 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 of1800 to 2300ms,the next trial began. The 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 a 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＂were shorter than the ＂face task＂when the targets displayed with a duration of150ms,but not1500ms. Furthermore,in the ＂face task＂,when the targets displayed with a duration of150ms,RTs were shorter for congruent compared to incongruent trials,i. e. ,a Stroop effect occurred; but in the ＂word task＂,there were no significant differences in RTs between incongruent trials and congruent trials. When the targets were displayed with a duration of1500ms,there was no significant emotional conflict effect in the face task and in the word task. And there were no significant differences in RTs between face task and word task in the condition of1500ms. The present study found that there was a Stroop asymmetry effect in the face-word task. Emotional word processing was not affected by emotional face. The duration of stimuli is an important factor in the face-word Stroop task. The face-word stroop task should be used carefully in future studies.