Department of Experimental Psychology, Ghent University, Ghent, Belgium.
Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium.
Psychophysiology. 2018 Mar;55(3). doi: 10.1111/psyp.13011. Epub 2017 Sep 20.
Recent associative models of cognitive control hypothesize that cognitive control can be learned (optimized) for task-specific settings via associations between perceptual, motor, and control representations, and, once learned, control can be implemented rapidly. Midfrontal brain areas signal the need for control, and control is subsequently implemented by biasing sensory representations, boosting or suppressing activity in brain areas processing task-relevant or task-irrelevant information. To assess the timescale of this process, we employed EEG. In order to pinpoint control implementation in specific sensory areas, we used a flanker task with incongruent flankers shown in only one hemifield (congruent flankers in the other hemifield) isolating their processing in the contralateral hemisphere. ERPs revealed fast modulations specifically in visual processing areas contralateral to the incongruent flankers. To test whether these modulations reflect increased or decreased processing of incongruent flankers, we investigated alpha power, a marker for attentional inhibition. Importantly, we show increased alpha power over visual areas processing incongruent flankers from 300 to 500 ms poststimulus onset. This suggests fast cognitive control by attentional inhibition for information disrupting goal-oriented actions. Additionally, we show that midfrontal theta earlier in the trial is also modulated by incongruency, and that theta power predicts subsequent alpha power modulations. This supports the hypothesis that midfrontal incongruency detection leads to control implementation, and reveals that these mechanisms take place on a fast, within-trial timescale.
最近的认知控制关联模型假设，通过感知、运动和控制表示之间的关联，认知控制可以针对特定任务的设置进行学习（优化），并且一旦学习，控制可以快速实施。前额叶脑区信号需要控制，随后通过偏向感觉表示来实施控制，增强或抑制处理与任务相关或不相关信息的脑区的活动。为了评估这个过程的时间尺度，我们采用了 EEG。为了在特定的感觉区域精确定位控制的实施，我们使用了一种带有不一致侧翼的侧翼任务（另一个侧翼在另一个半视野中是一致的），将它们在对侧半球中的处理孤立出来。ERP 揭示了仅在不一致侧翼所在的半视野中特异性地在视觉处理区域中快速调制。为了测试这些调制是否反映了对不一致侧翼的处理增加或减少，我们研究了 alpha 功率，这是注意力抑制的一个标志物。重要的是，我们发现在刺激后 300 到 500 毫秒期间，处理不一致侧翼的视觉区域的 alpha 功率增加。这表明注意力抑制对干扰目标导向行动的信息进行了快速的认知控制。此外，我们还表明，试验早期的前额叶 theta 也受到不一致性的调制，并且 theta 功率预测随后的 alpha 功率调制。这支持了前额叶不一致性检测导致控制实施的假设，并揭示了这些机制发生在快速的、试验内的时间尺度上。
