Attention comprises a wide set of processes such as phasic alertness, orienting, executive control, and the executive (i.e., detecting infrequent targets) and arousal (i.e., sustaining a fast reaction) vigilance components. Importantly, the effects of transcranial direct current stimulation (tDCS) over attentional functioning have been mostly addressed by measuring these processes separately and by delivering offline tDCS with low precision over the stimulation region. In the current study, we examined the effects of online High-Definition tDCS (HD-tDCS) over the behavioral and electrophysiological functioning of attentional and vigilance components. Participants (N = 92) were randomly assigned to one of three stimulation groups: right dorsolateral prefrontal cortex stimulation, right posterior parietal cortex (PPC) stimulation, and sham. All of them performed – in combination with the HD-tDCS protocol – an attentional networks task (ANTI-Vea) suitable to measure the executive and arousal components of vigilance along with three typical attentional functions: phasic alertness, orienting, and executive control. In addition, EEG was registered at the baseline and at the post-stimulation period. We observed that, regardless the stimulation region, online HD-tDCS: (a) reduced phasic alertness (p = .008), but did not modulated the orienting and executive control functioning; and (b) mitigated the executive vigilance decrement (p = .011), but did not modulated arousal vigilance across time-on-task. Interestingly, only HD-tDCS over PPC reduced considerably the increment of alpha power observed across time-on-task (p = .009). The current study provides further evidence for both an empirical dissociation between vigilance components and the cortical regions underlying attentional processes. We highlight the advantages of using online HD-tDCS to examine the stimulation effects on attentional and vigilance functioning.

注意包括一系列过程，例如阶段性警觉，定向，执行者控制以及执行者（即，检测不频繁的目标）和唤醒（即，维持快速反应）的警惕性组件。重要的是，经颅直流电刺激（tDCS）对注意力功能的影响已通过分别测量这些过程并通过在刺激区域以较低的精度传递离线tDCS来解决。在当前的研究中，我们检查了在线高清tDCS（HD-tDCS）对注意和警惕组件的行为和电生理功能的影响。参加人数 = 92）被随机分配到三个刺激组之一：右背外侧前额叶皮层刺激，右后顶叶皮层（PPC）刺激和假手术。所有这些都结合HD-tDCS协议执行了一项注意力网络任务（ANTI-Vea），该任务适用于衡量警惕性的执行和唤醒组件，以及三个典型的注意功能：阶段性警觉，定向和执行控制。此外，脑电图在基线和刺激后期进行了登记。我们观察到，无论刺激区域如何，在线HD-tDCS：（a）降低了阶段性警觉性（p  = .008），但未调节定向和执行控制功能；（b）减轻了行政人员的警觉性下降（p = .011），但并未在任务执行期间调节唤醒警觉性。有趣的是，只有通过PPC的HD-tDCS才能显着降低整个任务时间观察到的alpha功率增量（p  = .009）。当前的研究为警惕性成分与注意过程背后的皮质区域之间的经验解离提供了进一步的证据。我们强调了使用在线HD-tDCS来检查对注意力和警觉功能的刺激作用的优势。