The dorsolateral prefrontal cortex (DLPFC) is part of a network important for emotional regulation and the possibility of modulating activity in this region with transcranial direct current stimulation (TDCS) to change mood has gained great interest, particularly for application in clinical populations. Whilst results in major depressive disorder have been promising, less is known about the effects of TDCS on mood in non-clinical populations. We hypothesized that multiple sessions of anodal TDCS applied over the left DLPFC would enhance mood, primarily as measured by the Profile of Mood States questionnaire, in healthy older adults. In addition, in an exploratory analysis, we examined the potentially moderating role of working memory training. Working memory, just like emotional regulation, taxes the DLPFC, which suggests that engaging in a working memory task whilst receiving TDCS may have a different effect on activity in this region and consequently mood. A total of 123 participants between 65 and 75 years of age were randomly assigned to receive either 20 sessions of TDCS, with or without working memory training, or 20 sessions sham stimulation, with or without working memory training. We found no support for enhancement of mood due to TDCS in healthy older adults, with or without cognitive training and conclude that the TDCS protocol used is unlikely to improve mood in non-depressed older individuals.

中文翻译：

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没有证据表明在健康的老年人中多次经额颅直接刺激对情绪有任何影响。

背外侧前额叶皮层（DLPFC）是对情绪调节重要的网络的一部分，通过经颅直流电刺激（TDCS）调节该区域活动来改变情绪的可能性引起了人们的极大兴趣，尤其是在临床人群中的应用。尽管重度抑郁症的结果令人鼓舞，但对于非临床人群中TDCS对情绪的影响知之甚少。我们假设在健康的老年人中，在左DLPFC上多次使用阳极TDCS会增强情绪，这主要是通过情绪状态概况调查表测得的。此外，在探索性分析中，我们研究了工作记忆训练的潜在调节作用。工作记忆就像情绪调节一样，会向DLPFC征税，这表明在接受TDCS的同时从事工作记忆任务可能对该区域的活动以及情绪产生不同的影响。随机分配了123位年龄在65至75岁之间的参与者，接受或不接受工作记忆训练的20节TDCS，或接受或不接受工作记忆训练的20次假刺激。我们发现，在有或没有认知训练的情况下，健康的老年人均不支持由TDCS改善情绪，并得出结论，所使用的TDCS协议不太可能改善未抑郁的老年人的情绪。进行或不进行工作记忆训练，或进行20次假刺激，进行或不进行工作记忆训练。我们发现，在有或没有认知训练的情况下，健康的老年人均不支持由TDCS改善情绪，并得出结论，所使用的TDCS协议不太可能改善未抑郁的老年人的情绪。进行或不进行工作记忆训练，或进行20次假刺激，进行或不进行工作记忆训练。我们发现，在有或没有认知训练的情况下，健康的老年人均不支持由TDCS改善情绪，并得出结论，所使用的TDCS协议不太可能改善未抑郁的老年人的情绪。