Psychology Department, University of Illinois at Urbana, Champaign, USA; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana, Champaign, USA.
Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana, Champaign, USA; School of Psychology & Neuroscience, University of Glasgow, Scotland.
Neuroimage. 2023 Apr 15;270:119956. doi: 10.1016/j.neuroimage.2023.119956. Epub 2023 Feb 28.
EEG alpha power varies under many circumstances requiring visual attention. However, mounting evidence indicates that alpha may not only serve visual processing, but also the processing of stimuli presented in other sensory modalities, including hearing. We previously showed that alpha dynamics during an auditory task vary as a function of competition from the visual modality (Clements et al., 2022) suggesting that alpha may be engaged in multimodal processing. Here we assessed the impact of allocating attention to the visual or auditory modality on alpha dynamics at parietal and occipital electrodes, during the preparatory period of a cued-conflict task. In this task, bimodal precues indicated the modality (vision, hearing) relevant to a subsequent reaction stimulus, allowing us to assess alpha during modality-specific preparation and while switching between modalities. Alpha suppression following the precue occurred in all conditions, indicating that it may reflect general preparatory mechanisms. However, we observed a switch effect when preparing to attend to the auditory modality, in which greater alpha suppression was elicited when switching to the auditory modality compared to repeating. No switch effect was evident when preparing to attend to visual information (although robust suppression did occur in both conditions). In addition, waning alpha suppression preceded error trials, irrespective of sensory modality. These findings indicate that alpha can be used to monitor the level of preparatory attention to process both visual and auditory information, and support the emerging view that alpha band activity may index a general attention control mechanism used across modalities.
脑电图阿尔法波功率在需要视觉注意的许多情况下都会发生变化。然而，越来越多的证据表明，阿尔法波不仅可以用于视觉处理，还可以用于处理其他感觉模式（包括听觉）呈现的刺激。我们之前曾表明，在听觉任务中，阿尔法波的动力学变化与视觉模式的竞争有关（Clements 等人，2022 年），这表明阿尔法波可能参与了多模态处理。在这里，我们评估了在提示冲突任务的预备期期间，将注意力分配给视觉或听觉模式对顶叶和枕叶电极上阿尔法波动力学的影响。在这个任务中，双模态前提示指示与后续反应刺激相关的模态（视觉、听觉），使我们能够在特定模态的准备期间以及在模态之间切换时评估阿尔法波。在前提示后出现阿尔法波抑制，表明它可能反映了一般的预备机制。然而，当准备注意听觉模式时，我们观察到了一个切换效应，即在切换到听觉模式时，阿尔法波抑制比重复时更大。当准备注意视觉信息时，没有观察到切换效应（尽管在两种情况下都有明显的抑制）。此外，无论感觉模态如何，阿尔法波抑制的减弱都先于错误试验。这些发现表明，阿尔法波可以用于监测处理视觉和听觉信息的预备注意水平，并支持新兴的观点，即阿尔法波段活动可能指数跨模态使用的一般注意控制机制。
