College of Health, Medicine and Life Sciences, Brunel University London, Kingston Lane, UB8 3PH Uxbridge, UK; Centre for Cognitive Neuroscience, Brunel University London, UK; Department of Experimental and Applied Psychology, Institute for Brain and Behavior, Vrije Universiteit Amsterdam, the Netherlands.
Department of Experimental and Applied Psychology, Institute for Brain and Behavior, Vrije Universiteit Amsterdam, the Netherlands.
Neuroimage. 2021 Feb 1;226:117562. doi: 10.1016/j.neuroimage.2020.117562. Epub 2020 Nov 12.
An extensive body of work has shown that attentional capture is contingent on the goals of the observer: Capture is strongly reduced or even eliminated when an irrelevant singleton stimulus does not match the target-defining properties (Folk et al., 1992). There has been a long-standing debate on whether attentional capture can be explained by goal-driven and/or stimulus-driven accounts. Here, we shed further light on this matter by using EEG activity (raw EEG and alpha power) to provide a time-resolved index of attentional orienting towards salient stimuli that either matched or did not match target-defining properties. A search display containing the target stimulus was preceded by a spatially uninformative singleton cue that either matched the color of the upcoming target (contingent cues), or that appeared in an irrelevant color (non-contingent cues). Multivariate analysis of raw EEG and alpha power revealed preferential tuning to the location of both contingent and non-contingent cues, with a stronger bias towards contingent than non-contingent cues. The time course of these effects, however, depended on the neural signal. Raw EEG data revealed attentional orienting towards the contingent cue early on in the trial (>156 ms), while alpha power revealed sustained spatial selection in the cued locations at a later moment in the trial (>250 ms). Moreover, while raw EEG showed stronger capture by contingent cues during this early time window, an advantage for contingent cues arose during a later time window in alpha band activity. Thus, our findings suggest that raw EEG activity and alpha-band power tap into distinct neural processes that index separate aspects of covert spatial attention.
大量研究表明，注意力捕获取决于观察者的目标：当无关的单个刺激与目标定义属性不匹配时，捕获会大大减少甚至消除（Folk 等人，1992）。长期以来，关于注意力捕获是否可以用目标驱动和/或刺激驱动的解释来解释一直存在争议。在这里，我们通过使用 EEG 活动（原始 EEG 和 alpha 功率）来进一步阐明这个问题，为朝向显著刺激的注意力定向提供了一个时间分辨的指数，这些刺激要么与目标定义属性匹配，要么不匹配。一个包含目标刺激的搜索显示在一个空间上无信息的单个线索之前，该线索要么与即将到来的目标的颜色匹配（偶然线索），要么出现在无关的颜色中（非偶然线索）。原始 EEG 和 alpha 功率的多元分析揭示了对偶然和非偶然线索位置的优先调整，对偶然线索的偏好强于非偶然线索。然而，这些效应的时间进程取决于神经信号。原始 EEG 数据揭示了在试验早期（>156 毫秒）朝向偶然线索的注意力定向，而 alpha 功率揭示了在试验后期（>250 毫秒）在提示位置的持续空间选择。此外，虽然原始 EEG 在这个早期时间窗口显示出对偶然线索更强的捕获，但在 alpha 波段活动的后期时间窗口中，偶然线索出现了优势。因此，我们的发现表明，原始 EEG 活动和 alpha 波段功率利用了不同的神经过程，这些过程反映了隐蔽空间注意力的不同方面。
