Department of Experimental Clinical and Health Psychology, Ghent University, Ghent, Belgium.
PLoS One. 2013 May 21;8(5):e62219. doi: 10.1371/journal.pone.0062219. Print 2013.
Transcranial Direct Current Stimulation (tDCS) is a neuromodulation technique with promising results for enhancing cognitive information processes. So far, however, research has mainly focused on the effects of tDCS on cognitive control operations for non-emotional material. Therefore, our aim was to investigate the effects on cognitive control considering negative versus positive material. For this sham-controlled, within-subjects study, we selected a homogeneous sample of twenty-five healthy participants. By using behavioral measures and event related potentials (ERP) as indexes, we aimed to investigate whether a single session of anodal tDCS of the left dorsolateral prefrontal cortex (DLPFC) would have specific effects in enhancing cognitive control for positive and negative valenced stimuli. After tDCS over the left DLPFC (and not sham control stimulation), we observed more negative N450 amplitudes along with faster reaction times when inhibiting a habitual response to happy compared to sad facial expressions. Gender did not influence the effects of tDCS on cognitive control for emotional information. In line with the Valence Theory of side-lateralized activity, this stimulation protocol might have led to a left dominant (relative to right) prefrontal cortical activity, resulting in augmented cognitive control specifically for positive relative to negative stimuli. To verify that tDCS induces effects that are in line with all aspects of the well known Valence Theory, future research should investigate the effects of tDCS over the left vs. right DLPFC on cognitive control for emotional information.
经颅直流电刺激（tDCS）是一种神经调节技术，在增强认知信息处理方面具有广阔的前景。然而，到目前为止，研究主要集中在 tDCS 对非情感材料的认知控制操作的影响上。因此，我们的目的是研究考虑到负性和正性材料时认知控制的影响。在这项假刺激对照、被试内研究中，我们选择了 25 名健康参与者的同质样本。通过使用行为测量和事件相关电位（ERP）作为指标，我们旨在研究单次左外侧前额叶皮层（DLPFC）阳极 tDCS 是否会对正性和负性效价刺激的认知控制产生特定影响。在对左侧 DLPFC 进行 tDCS（而非假刺激）之后，与对悲伤表情相比，当抑制对快乐面部表情的习惯性反应时，我们观察到更负的 N450 振幅和更快的反应时间。性别并没有影响 tDCS 对情绪信息的认知控制的影响。与侧化活动的效价理论一致，这种刺激方案可能导致左优势（相对于右优势）前额叶皮质活动，从而增强了对正性刺激的认知控制，而对负性刺激的认知控制则减弱。为了验证 tDCS 诱导的效果与众所周知的效价理论的各个方面一致，未来的研究应该调查 tDCS 对左 DLPFC 与右 DLPFC 对情绪信息的认知控制的影响。
