关键词: 情绪诱发视盲, 情绪注意控制, 前额theta, 时频分析

Abstract: Previous research on emotion induced blindness (EIB) have revealed two crucial competition processing stages respectively as early attention selection and late working memory consolidation between targets and emotional distractors. For the first competition stage at early attention selection, previous studies has found a posterior N2 effect which indicated an attention capture or recognition mechanism of bilateral temporal-occipital regions in the EIB processes. In recent studies, however, this N2 effect has been regarded as N2pc rather than EPN. So this posterior N2 could not reflect the emotional attention process in the EIB. Besides that, now we still know less about how individuals control attention processes to emotional distractors before identifying the targets. Considering that, the intention of the present study was to investigate the potential emotional attention control mechanism in the EIB processes. To achieve this intention, the present study employed a typical EIB task. In this task, participants had to identify indoor or outdoor pictures in rapid serial visual presentation (RSVP) streams. Negative and neutral pictures were used as irrelevant emotional distractors. In addition, a control condition (no distractor) was employed as baseline. When participants give correct responses in this EIB task, their EEG data was recorded and analysis. To find new evidence that support the emotional attention control mechanism in EIB, we utilized the time-frequency (TF) analysis method in the current study. In behavioral results, analysis on participants’ response accuracies shown a main effect of distractors, which revealed a typical EIB effect. On the other hand, TF analysis on EEG data show a frontal theta synchronizations (i.e., FMθ; 4-7 Hz) at 200-500 ms after irrelevant emotional distractor onset. This frontal theta synchronization appeared on either negative distractor condition or neutral distractor condition, but disappeared in the control condition. A further analysis distinguishing negative distractor or neutral distractor conditions found two regions of interests (ROIs) of the theta synchronization. The first one appeared at 150-370 ms at the occipital-temporal region, whereas the second one appear 170-350 ms at the left frontal region. The former was consistent with the posterior N2 effect in previous EIB studies, while the latter was consistent with the general emotional attention control role of the left frontal regions. To sum up, our study demonstrated that the emotional attention control mechanism in the EIB was indeed a top-down control mechanism, which were not only relied on attention selection function of occipital-temporal regions, but also relied on emotion control function of frontal regions.

Key words: Emotion induced blindness (EIB), emotion attention control, frontal theta, time-frequency analysis