Department of Psychiatry, University of California, Irvine, Irvine, CA 92868, USA.
Soc Cogn Affect Neurosci. 2013 Jan;8(1):100-11. doi: 10.1093/scan/nss060. Epub 2012 May 29.
Long-term Vipassana meditators sat in meditation vs. a control (instructed mind wandering) states for 25 min, electroencephalography (EEG) was recorded and condition order counterbalanced. For the last 4 min, a three-stimulus auditory oddball series was presented during both meditation and control periods through headphones and no task imposed. Time-frequency analysis demonstrated that meditation relative to the control condition evinced decreased evoked delta (2-4 Hz) power to distracter stimuli concomitantly with a greater event-related reduction of late (500-900 ms) alpha-1 (8-10 Hz) activity, which indexed altered dynamics of attentional engagement to distracters. Additionally, standard stimuli were associated with increased early event-related alpha phase synchrony (inter-trial coherence) and evoked theta (4-8 Hz) phase synchrony, suggesting enhanced processing of the habituated standard background stimuli. Finally, during meditation, there was a greater differential early-evoked gamma power to the different stimulus classes. Correlation analysis indicated that this effect stemmed from a meditation state-related increase in early distracter-evoked gamma power and phase synchrony specific to longer-term expert practitioners. The findings suggest that Vipassana meditation evokes a brain state of enhanced perceptual clarity and decreased automated reactivity.
长期内观冥想者在冥想和控制（指导思维漫游）状态下各静坐 25 分钟，记录脑电图（EEG）并平衡条件顺序。在最后 4 分钟，耳机中同时呈现三刺激听觉Oddball 系列，在冥想和控制期间不施加任何任务。时频分析表明，与对照条件相比，冥想状态下对分心刺激的诱发 delta（2-4 Hz）功率降低，同时相关的晚期（500-900 ms）alpha-1（8-10 Hz）活动的事件相关减少，这表明对分心物的注意力参与的动态发生改变。此外，标准刺激与早期相关的 alpha 阶段同步性（试验间相干性）和诱发 theta（4-8 Hz）相位同步性增加有关，表明对习惯化的标准背景刺激的处理得到增强。最后，在冥想期间，不同刺激类别的早期诱发伽马功率差异更大。相关分析表明，这种效应源于冥想状态下对更长时间的专家实践者的早期分心诱发伽马功率和相位同步性的增加。研究结果表明，内观冥想会引起大脑状态的增强，提高感知清晰度，降低自动反应性。
