Institute of Psychology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria.
Institute of Psychology, University of Graz, Universitätsplatz 2, A-8010 Graz, Austria.
Neuropsychologia. 2018 Sep;118(Pt A):91-98. doi: 10.1016/j.neuropsychologia.2017.10.035. Epub 2017 Oct 31.
Transcranial alternating current stimulation (tACS) is a non-invasive brain stimulation method that allows to directly modulate brain oscillations of a given frequency. Using this method, it was recently shown that increasing alpha (10Hz) oscillations improved creative ideation with figural material and that increasing gamma (40Hz) oscillations speeded up performance in a figural matrices intelligence task. The aim of the present study was to examine whether these findings generalize to verbal creativity and intelligence tasks. In addition, we explored whether the stimulation effects are moderated by individual differences in creative potential and intelligence. Twenty-two adults received 10Hz, 40Hz and sham tACS while they worked on a verbal creativity (alternate uses) task and a verbal intelligence (anagram) task. Analyses revealed that 10Hz stimulation had a marginally significant effect on ideational fluency in the alternate uses task, whereas originality was unaffected. The beneficial effect of stimulation on fluency tended to emerge mainly in the individuals with higher creative potential. In the verbal intelligence task, in contrast, 40Hz stimulation did neither impact on performance nor interacted with individual differences in intelligence. These findings provide first tentative evidence that enhancing alpha oscillations through tACS may improve creative thinking not only in the figural but also in the verbal domain. The previously reported beneficial effect of gamma tACS on figural intelligence, however, could not be observed in a verbal task. In sum, the present study further corroborates the causal link between alpha oscillations and creative thinking and suggests that tACS may be a promising tool to enhance cognitive processes.
经颅交流电刺激（tACS）是一种非侵入性的脑刺激方法，可以直接调节特定频率的脑振荡。使用这种方法，最近的研究表明，增加 alpha（10Hz）振荡可以提高图形材料的创造性思维，而增加 gamma（40Hz）振荡可以提高图形矩阵智力任务的表现。本研究的目的是检验这些发现是否适用于言语创造力和智力任务。此外，我们还探讨了刺激效果是否受到创造性潜力和智力个体差异的调节。22 名成年人在进行言语创造力（替代用途）任务和言语智力（字谜）任务时接受了 10Hz、40Hz 和假 tACS 刺激。分析表明，10Hz 刺激对替代用途任务中的创意流畅性有显著影响，而新颖性不受影响。刺激对流畅性的有益影响倾向于主要出现在具有较高创造性潜力的个体中。相比之下，在言语智力任务中，40Hz 刺激既没有影响表现，也没有与智力的个体差异相互作用。这些发现提供了初步证据，表明通过 tACS 增强 alpha 振荡可能不仅在图形领域，而且在言语领域改善创造性思维。然而，在言语任务中，以前报道的 gamma tACS 对图形智力的有益影响并没有被观察到。总之，本研究进一步证实了 alpha 振荡与创造性思维之间的因果关系，并表明 tACS 可能是增强认知过程的有前途的工具。
