Hopfinger Joseph B, Parsons Jonathan, Fröhlich Flavio
a Department of Psychology & Neuroscience , University of North Carolina at Chapel Hill , Chapel Hill , NC , USA.
b Departments of Psychiatry, Cell Biology and Physiology, Biomedical Engineering, and Neurology , University of North Carolina , Chapel Hill , NC , USA.
Cogn Neurosci. 2017 Apr;8(2):102-111. doi: 10.1080/17588928.2016.1194261. Epub 2016 Jun 14.
Previous electrophysiological studies implicate both alpha (8-12 Hz) and gamma (>30 Hz) neural oscillations in the mechanisms of selective attention. Here, participants preformed two separate visual attention tasks, one endogenous and one exogenous, while transcranial alternating current stimulation (tACS), at 10 Hz, 40 Hz, or sham, was applied to the right parietal lobe. Our results provide new evidence for the roles of gamma and alpha oscillations in voluntary versus involuntary shifts of attention. Gamma (40 Hz) stimulation resulted in improved disengagement from invalidly cued targets in the endogenous attention task, whereas alpha stimulation (10 Hz) had no effect on endogenous attention, but increased the exogenous cuing effect. These findings agree with previous studies suggesting that right inferior parietal regions may be especially important for the disengagement of attention, and go further to provide details about the specific type of oscillatory neural activity within that brain region that is differentially involved in endogenous versus exogenous attention. Our results also have potential implications for the plasticity and training of attention systems.
先前的电生理研究表明，α（8 - 12赫兹）和γ（>30赫兹）神经振荡都参与了选择性注意机制。在此，参与者进行了两项独立的视觉注意任务，一项是内源性的，一项是外源性的，同时将10赫兹、40赫兹的经颅交流电刺激（tACS）或伪刺激施加于右侧顶叶。我们的研究结果为γ和α振荡在注意的自愿性与非自愿性转移中的作用提供了新证据。γ（40赫兹）刺激导致在内源性注意任务中从错误提示的目标上更好地脱离，而α刺激（10赫兹）对内源性注意没有影响，但增强了外源性提示效应。这些发现与先前的研究一致，表明右下顶叶区域可能对注意的脱离尤为重要，并进一步提供了关于该脑区内特定类型的振荡神经活动的细节，这些活动在内源性与外源性注意中存在差异。我们的研究结果对注意系统的可塑性和训练也具有潜在意义。
