Voytek Bradley, Canolty Ryan T, Shestyuk Avgusta, Crone Nathan E, Parvizi Josef, Knight Robert T
Helen Wills Neuroscience Institute, University of California Berkeley Berkeley, CA, USA.
Front Hum Neurosci. 2010 Oct 19;4:191. doi: 10.3389/fnhum.2010.00191. eCollection 2010.
The phase of ongoing theta (4-8 Hz) and alpha (8-12 Hz) electrophysiological oscillations is coupled to high gamma (80-150 Hz) amplitude, which suggests that low-frequency oscillations modulate local cortical activity. While this phase-amplitude coupling (PAC) has been demonstrated in a variety of tasks and cortical regions, it has not been shown whether task demands differentially affect the regional distribution of the preferred low-frequency coupling to high gamma. To address this issue we investigated multiple-rhythm theta/alpha to high gamma PAC in two subjects with implanted subdural electrocorticographic grids. We show that high gamma amplitude couples to the theta and alpha troughs and demonstrate that, during visual tasks, alpha/high gamma coupling preferentially increases in visual cortical regions. These results suggest that low-frequency phase to high-frequency amplitude coupling is modulated by behavioral task and may reflect a mechanism for selection between communicating neuronal networks.
持续的θ波（4 - 8赫兹）和α波（8 - 12赫兹）电生理振荡的相位与高γ波（80 - 150赫兹）的振幅耦合，这表明低频振荡调节局部皮层活动。虽然这种相位 - 振幅耦合（PAC）已在各种任务和皮层区域得到证实，但尚未表明任务需求是否会差异地影响与高γ波的首选低频耦合的区域分布。为了解决这个问题，我们在两名植入硬膜下皮层电图网格的受试者中研究了多节律的θ/α波到高γ波的PAC。我们表明，高γ波振幅与θ波和α波的波谷耦合，并证明在视觉任务期间，α/高γ波耦合在视觉皮层区域优先增加。这些结果表明，低频相位到高频振幅的耦合受行为任务调节，可能反映了在相互通信的神经元网络之间进行选择的一种机制。
