Keil Andreas, Ihssen Niklas, Heim Sabine
University of Konstanz, Konstanz, Germany.
BMC Biol. 2006 Jul 20;4:23. doi: 10.1186/1741-7007-4-23.
The present study aimed to investigate the time course of electrocortical facilitation for affectively arousing written words during the so-called 'attentional blink' (AB) period in a rapid serial visual presentation (RSVP) task. The AB refers to a period of reduced awareness for second-target stimuli following a first target by an interval of about 200-500 ms. Pleasant, neutral, and unpleasant written verbs were used as second targets in an 8.6-Hz RSVP paradigm that contained affectively neutral words as distractors. Replicating and extending behavioral studies, we expected that emotional second targets would be associated with better identification accuracy and greater electrocortical activity, compared with neutral targets.
The steady-state visual evoked potential was recorded using 129 scalp electrodes. The time-varying energy at the presentation frequency of 8.6 Hz was extracted as a continuous measure of electrocortical activity related to the RSVP stream. Behavioral data showed that at an inter-target interval of 232 ms, the report for emotionally arousing (pleasant and unpleasant) words was more accurate than for neutral control words. This result was mirrored by the electrocortical response at posterior sensors, which showed rapid amplitude enhancement (120-270 ms after T2 onset) for pleasant and unpleasant targets specifically.
The present data suggest that identification facilitation for emotionally arousing target words in the AB is related to rapid enhancement of sensory processing. Affectively arousing information is preferentially selected at the level of early perceptual analysis, leading to facilitation at later stages of processing, including consolidation in working memory and visual awareness.
本研究旨在探究在快速序列视觉呈现（RSVP）任务的所谓“注意瞬脱”（AB）期间，情感唤起性书面词语的皮质电易化的时间进程。AB是指在第一个目标之后约200 - 500毫秒的间隔内，对第二个目标刺激的意识降低的时间段。在一个8.6赫兹的RSVP范式中，使用愉快、中性和不愉快的书面动词作为第二个目标，该范式包含情感中性的词语作为干扰项。重复并扩展行为学研究，我们预期与中性目标相比，情感性的第二个目标将与更高的识别准确率和更大的皮质电活动相关。
使用129个头皮电极记录稳态视觉诱发电位。提取8.6赫兹呈现频率下随时间变化的能量，作为与RSVP流相关的皮质电活动的连续测量指标。行为数据表明，在目标间隔为232毫秒时，对情感唤起性（愉快和不愉快）词语的报告比对中性对照词语更准确。后头部传感器的皮质电反应反映了这一结果，该反应显示愉快和不愉快目标在特定时间（T2开始后120 - 270毫秒）迅速增强。
目前的数据表明，AB期间对情感唤起性目标词语的识别易化与感觉加工的快速增强有关。情感唤起性信息在早期知觉分析水平上被优先选择，从而在后期加工阶段，包括工作记忆巩固和视觉意识方面产生易化作用。
