Koivisto Mika, Revonsuo Antti
Centre for Cognitive Neuroscience, University of Turku, 20014 Turku, Finland.
Brain Res. 2008 Jan 16;1189:115-26. doi: 10.1016/j.brainres.2007.10.082. Epub 2007 Nov 4.
Attending to the first target in rapid serial visual presentation (RSVP) interferes with processing of the second target so that the participants fail to recognize the second target if the targets are separated by a stimulus onset asynchrony of 200-500 ms. This phenomenon is attentional blink (AB). Repetition blindness (RB) is an additional difficulty to recognize the second occurrence of the same stimulus in RSVP. A controversial issue in studies of both deficits is the processing level at which they occur. To compare the timing and mechanisms of AB and RB directly during the same RSVP stream, we recorded event-related potentials (ERPs) in response to repeated and unrepeated targets. Comparable to earlier ERP studies on visual awareness, the results showed for both types of targets a negative amplitude difference between ERPs to consciously recognized and unrecognized targets during 250-350 ms from stimulus onset, suggesting that both AB and RB are associated with deficits of conscious perception, occurring at earlier stages than access to working memory. However, the perceptual deficit in RB is more severe, which may be related to higher overall negativity in response to repeated targets observed 150-300 ms after stimulus onset, suggesting stronger cortical baseline activation and higher perceptual threshold for repeated targets as compared with unrepeated ones.
在快速序列视觉呈现（RSVP）中关注第一个目标会干扰对第二个目标的处理，以至于如果目标之间的刺激起始异步时间为200 - 500毫秒，参与者就无法识别第二个目标。这种现象就是注意瞬脱（AB）。重复盲视（RB）是在RSVP中识别同一刺激的第二次出现时的另一个困难。在对这两种缺陷的研究中，一个有争议的问题是它们发生的处理水平。为了在同一RSVP流中直接比较AB和RB的时间和机制，我们记录了对重复和未重复目标做出反应的事件相关电位（ERP）。与早期关于视觉意识的ERP研究类似，结果显示，对于这两种类型的目标，从刺激开始后的250 - 350毫秒内，ERP中对有意识识别和未识别目标的负向振幅存在差异，这表明AB和RB都与意识知觉缺陷有关，发生在比进入工作记忆更早的阶段。然而，RB中的知觉缺陷更为严重，这可能与刺激开始后150 - 300毫秒观察到的对重复目标的更高整体负向性有关，这表明与未重复目标相比，重复目标的皮层基线激活更强，知觉阈值更高。
