Nitsche M A, Koschack J, Pohlers H, Hullemann S, Paulus W, Happe S
Department Clinical Neurophysiology, Georg-August-University Goettingen, Germany.
Front Psychiatry. 2012 Jun 18;3:58. doi: 10.3389/fpsyt.2012.00058. eCollection 2012.
The prefrontal cortex is involved in mood and emotional processing. In patients suffering from depression, the left dorsolateral prefrontal cortex (DLPFC) is hypoactive, while activity of the right DLPFC is enhanced. Counterbalancing these pathological excitability alterations by repetitive transcranial magnetic stimulation (rTMS) or transcranial direct current stimulation (tDCS) improves mood in these patients. In healthy subjects, however, rTMS of the same areas has no major effect, and the effects of tDCS are mixed. We aimed to evaluate the effects of prefrontal tDCS on emotion and emotion-related cognitive processing in healthy humans. In a first study, we administered excitability-enhancing anodal, excitability-diminishing cathodal, and placebo tDCS to the left DLPFC, combined with antagonistic stimulation of the right frontopolar cortex, and tested acute emotional changes by an adjective checklist. Subjective emotions were not influenced by tDCS. Emotional face identification, however, which was explored in a second experiment, was subtly improved by a tDCS-driven excitability modulation of the prefrontal cortex, markedly by anodal tDCS of the left DLPFC for positive emotional content. We conclude that tDCS of the prefrontal cortex improves emotion processing in healthy subjects, but does not influence subjective emotional state.
前额叶皮质参与情绪和情感加工。在抑郁症患者中，左侧背外侧前额叶皮质（DLPFC）活动减退，而右侧DLPFC活动增强。通过重复经颅磁刺激（rTMS）或经颅直流电刺激（tDCS）来平衡这些病理性兴奋性改变可改善这些患者的情绪。然而，在健康受试者中，相同区域的rTMS没有显著影响，tDCS的效果则好坏参半。我们旨在评估前额叶tDCS对健康人情绪及与情绪相关的认知加工的影响。在第一项研究中，我们对左侧DLPFC施加增强兴奋性的阳极、减弱兴奋性的阴极和安慰剂tDCS，并联合对右侧额极皮质进行拮抗刺激，通过形容词检查表测试急性情绪变化。主观情绪未受tDCS影响。然而，在第二项实验中所探究的情绪面孔识别，通过tDCS驱动的前额叶皮质兴奋性调制得到了轻微改善，对于积极情绪内容，左侧DLPFC的阳极tDCS有显著改善作用。我们得出结论，前额叶皮质的tDCS可改善健康受试者的情绪加工，但不影响主观情绪状态。
