Laboratory of Experimental Neuropsychology, Neurology Clinic, Geneva University Hospitals, Switzerland.
Brain Topogr. 2012 Apr;25(2):167-81. doi: 10.1007/s10548-011-0199-5. Epub 2011 Aug 21.
The attentional blink (AB) is a transient attentional deficit that occurs when two stimuli that must both be detected are presented within an interval of less than 500 ms. Event-related potential (ERP) investigations have suggested that the AB affects a specific component, the P3, which is suppressed when targets are blinked. In view of the link between the P3 and working memory, it has been suggested that the AB might be due to the inability of the blinked target to access working memory. Interestingly, it seems that faces, due to their saliency, might escape the AB effect when cross-category detection is required (i.e., when the targets are composed of faces versus other categories of stimuli). In the present study we investigated this phenomenon in an event-related potential (ERP) study using upright and inverted faces as targets. In a first task, the participants were asked to identify two successive targets, the first composed of geometric shapes and the second of upright or inverted faces. A second control task, identical to the first was also performed, in which only the second targets had to be identified in order to compare ERPs. ERPs and scalp topographies of physically identical sequences of events, differing only by the attentional involvement, were thus compared. Behavioural results showed that faces indeed escape the AB while inverted faces do not. However, the electrophysiological findings showed that when attention was engaged in a previous stimulus (at the shortest lag times), both upright and inverted faces showed a decreased amplitude in the 150-260 ms time period, in addition to a lower P3. At longer lags, when the AB was no longer observed, no ERP differences were found. Our data demonstrate that, although faces escape the attentional blink, previous attentional involvement occurs much earlier than described for other categories of stimuli. This suggests that faces are subjected to an early selection which might allow rapid re-allocation of attention to the stimulus if it is deemed meaningful.
注意瞬脱（AB）是一种短暂的注意力缺陷，当两个都必须被检测到的刺激在小于 500 毫秒的时间间隔内呈现时就会发生。事件相关电位（ERP）的研究表明，AB 影响一个特定的成分，即 P3，当目标被眨眼时，P3 就会被抑制。鉴于 P3 与工作记忆之间的联系，有人认为 AB 可能是由于眨眼目标无法访问工作记忆所致。有趣的是，由于其显著性，当需要跨类别检测（即目标由面孔与其他类别的刺激组成）时，面孔似乎可以逃脱 AB 效应。在本研究中，我们使用直立和倒置的面孔作为目标，在事件相关电位（ERP）研究中研究了这一现象。在第一个任务中，要求参与者识别两个连续的目标，第一个目标由几何形状组成，第二个目标由直立或倒置的面孔组成。第二个控制任务与第一个任务完全相同，也需要识别第二个目标，以便比较 ERP。因此，比较了仅在注意参与前一个刺激（在最短的滞后时间）时，物理上相同的事件序列的 ERP 和头皮地形图。行为结果表明，面孔确实逃脱了 AB，而倒置的面孔则没有。然而，电生理结果表明，当注意力在前一个刺激上（在最短的滞后时间）时，无论是直立的还是倒置的面孔，在 150-260 毫秒的时间段内，振幅都会降低，此外 P3 也会降低。在较长的滞后时间，当不再观察到 AB 时，没有发现 ERP 差异。我们的数据表明，尽管面孔逃脱了注意力瞬脱，但之前的注意力参与发生得比其他类别的刺激早得多。这表明，面孔受到早期选择的影响，如果它被认为是有意义的，就可以迅速重新分配注意力。
