Department of Psychology, Drexel University, 3201 Chestnut St., Philadelphia, PA, 19140, USA.
University of Connecticut, Storrs, USA.
Sci Rep. 2021 Apr 23;11(1):8874. doi: 10.1038/s41598-021-85804-3.
Neuroimaging and transcranial direct current stimulation (tDCS) research has revealed that generating novel ideas is associated with both reductions and increases in prefrontal cortex (PFC) activity, and engagement of posterior occipital cortex, among other regions. However, there is substantial variability in the robustness of these tDCS-induced effects due to heterogeneous sample sizes, different creativity measures, and methodological diversity in the application of tDCS across laboratories. To address these shortcomings, we used twelve different montages within a standardized tDCS protocol to investigate how altering activity in frontotemporal and occipital cortex impacts creative thinking. Across four experiments, 246 participants generated either the common or an uncommon use for 60 object pictures while undergoing tDCS. Participants also completed a control short-term memory task. We applied active tDCS for 20 min at 1.5 mA through two 5 cm × 5 cm electrodes over left or right ventrolateral prefrontal (areas F7, F8) or occipital (areas O1, O2) cortex, concurrent bilateral stimulation of these regions across polarities, or sham stimulation. Cathodal stimulation of the left, but not right, ventrolateral PFC improved fluency in creative idea generation, but had no effects on originality, as approximated by measures of semantic distance. No effects were obtained for the control tasks. Concurrent bilateral stimulation of the ventrolateral PFC regardless of polarity direction, and excitatory stimulation of occipital cortex did not alter task performance. Highlighting the importance of cross-experimental methodological consistency, these results extend our past findings and contribute to our understanding of the role of left PFC in creative thinking.
神经影像学和经颅直流电刺激（tDCS）研究表明，产生新想法与前额叶皮层（PFC）活动的减少和增加以及枕后顶叶皮层等区域的参与有关。然而，由于样本大小不均、不同的创造力测量方法以及 tDCS 在实验室之间应用的方法多样性，这些 tDCS 诱导效应的稳健性存在很大差异。为了解决这些缺点，我们在标准化 tDCS 方案中使用了 12 种不同的刺激模式，以研究改变额顶叶和枕叶皮层的活动如何影响创造性思维。在四个实验中，246 名参与者在接受 tDCS 的同时，对 60 张物体图片进行了常见或不常见的用途的生成。参与者还完成了一项控制短期记忆任务。我们通过两个 5cm×5cm 的电极在左或右外侧前额叶（区域 F7、F8）或枕叶（区域 O1、O2）上施加 1.5mA 的电流，持续 20 分钟，进行了主动 tDCS 治疗。这些区域的极性相反的双侧刺激或假刺激。左侧（但不是右侧）外侧前额叶的阴极刺激提高了创造性思维产生的流畅性，但对原创性没有影响，这可以通过语义距离的测量来近似。控制任务没有效果。无论极性方向如何，外侧前额叶的双侧同步刺激，以及枕叶皮层的兴奋刺激，都不会改变任务表现。这些结果突出了跨实验方法一致性的重要性，扩展了我们过去的发现，并有助于我们理解左前额叶在创造性思维中的作用。
