Department of Psychology, National University of Singapore, Singapore, Singapore; Asia Research Institute, National University of Singapore, Singapore, Singapore.
Experimental Psychology Lab, Department of Psychology, Center for Excellence 'Hearing4all', European Medical School, Carl von Ossietzky University, Oldenburg, Germany.
Neuroimage. 2015 May 1;111:267-76. doi: 10.1016/j.neuroimage.2015.02.024. Epub 2015 Feb 19.
Temporal regularities in the environment are thought to guide the allocation of attention in time. Here, we explored whether entrainment of neuronal oscillations underpins this phenomenon. Participants viewed a regular stream of images in silence, or in-synchrony or out-of-synchrony with an unmarked beat position of a slow (1.3 Hz) auditory rhythm. Focusing on occipital recordings, we analyzed evoked oscillations shortly before and event-related potentials (ERPs) shortly after image onset. The phase of beta-band oscillations in the in-synchrony condition differed from that in the out-of-synchrony and silence conditions. Additionally, ERPs revealed rhythm effects for a stimulus onset potential (SOP) and the N1. Both were more negative for the in-synchrony as compared to the out-of-synchrony and silence conditions and their amplitudes positively correlated with the beta phase effects. Taken together, these findings indicate that rhythmic expectations are supported by a reorganization of neural oscillations that seems to benefit stimulus processing at expected time points. Importantly, this reorganization emerges from global rhythmic cues, across modalities, and for frequencies significantly higher than the external rhythm. As such, our findings support the idea that entrainment of neuronal oscillations represents a general mechanism through which the brain uses predictive elements in the environment to optimize attention and stimulus perception.
人们认为环境中的时间规律指导着注意力在时间上的分配。在这里，我们探讨了神经元振荡的同步是否是这种现象的基础。参与者在安静、同步或不同步的情况下观看一系列规则的图像，与一个缓慢（1.3 Hz）的听觉节奏的无标记节拍位置同步。我们专注于枕部记录，在图像出现之前和之后不久分析诱发的振荡和事件相关电位（ERP）。在同步条件下，β波段振荡的相位与不同步和安静条件下的相位不同。此外，ERP 揭示了刺激起始电位（SOP）和 N1 的节律效应。与不同步和安静条件相比，同步条件下的 SOP 和 N1 更负，其振幅与β相位效应呈正相关。总之，这些发现表明，节律预期得到了神经振荡重组的支持，这种重组似乎有利于在预期时间点处理刺激。重要的是，这种重组源自跨模态的全局节律线索，且频率明显高于外部节律。因此，我们的发现支持了这样一种观点，即神经元振荡的同步代表了大脑利用环境中的预测元素来优化注意力和刺激感知的一种普遍机制。
