Making Waves in the Stream of Consciousness: Entraining Oscillations in EEG Alpha and Fluctuations in Visual Awareness with Rhythmic Visual Stimulation
Making Waves in the Stream of Consciousness: Entraining Oscillations in EEG Alpha and Fluctuations in Visual Awareness with Rhythmic Visual Stimulation
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DOI：
10.1162/jocn_a_00288
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发表时间：
2012-12-01
影响因子：
3.2
通讯作者：
Gratton, Gabriele
中科院分区：
文献类型：
--
作者：
Mathewson, Kyle E.;Prudhomme, Christopher;Gratton, Gabriele
在我们的感官世界中，节奏事件是很常见的。时间序列可以用来预测即将发生的事件的时间，从而促进它们的处理。事实上，认知理论长期以来一直认为存在内部振荡器，其时间可以被环境中持续的周期性刺激所吸引，作为时间注意力的机制。最近，灵长类动物大脑的记录显示了这些假设的内部振荡的电生理证据。我们假设，有节奏的视觉刺激可以夹带正在进行的神经振荡在人类，锁定的兴奋性周期的时间，他们代表，从而提高后续可预测的刺激处理。在这里，我们报告的证据夹带的神经振荡的可预测的周期性刺激的α频段，并首次表明，现有的脑振荡的相位不仅可以修改响应于有节奏的视觉刺激，但由此产生的锁相波动的兴奋性导致伴随波动的视觉意识在人类。这种夹带效应依赖于实验前自发α功率的量和每次试验前12 Hz振荡的水平，并且不能用诱发活动来解释。正在进行的神经兴奋性周期的夹带引起的意识的节律性波动支持一个拟议的作用，作为一个脉冲抑制皮层活动的α振荡。此外，这些数据为我们的意识体验的量化性质提供了证据，并揭示了一种强大的机制，通过这种机制，时间注意力和感知快照可以被操纵和控制。
Rhythmic events are common in our sensory world. Temporal regularities could be used to predict the timing of upcoming events, thus facilitating their processing. Indeed, cognitive theories have long posited the existence of internal oscillators whose timing can be entrained to ongoing periodic stimuli in the environment as a mechanism of temporal attention. Recently, recordings from primate brains have shown electrophysiological evidence for these hypothesized internal oscillations. We hypothesized that rhythmic visual stimuli can entrain ongoing neural oscillations in humans, locking the timing of the excitability cycles they represent and thus enhancing processing of subsequently predictable stimuli. Here we report evidence for entrainment of neural oscillations by predictable periodic stimuli in the alpha frequency band and show for the first time that the phase of existing brain oscillations cannot only be modified in response to rhythmic visual stimulation but that the resulting phase-locked fluctuations in excitability lead to concomitant fluctuations in visual awareness in humans. This entrainment effect was dependent on both the amount of spontaneous alpha power before the experiment and the level of 12-Hz oscillation before each trial and could not be explained by evoked activity. Rhythmic fluctuations in awareness elicited by entrainment of ongoing neural excitability cycles support a proposed role for alpha oscillations as a pulsed inhibition of cortical activity. Furthermore, these data provide evidence for the quantized nature of our conscious experience and reveal a powerful mechanism by which temporal attention as well as perceptual snapshots can be manipulated and controlled.