Effects of Transcranial Direct Current Stimulation on Brain Networks Related to Creative Thinking

Abstract

Human creative thinking is unique and capable of generating novel and valuable ideas. Recent research has clarified the contribution of different brain networks (default mode network, DN; executive control network; salience network) to creative thinking. However, the effects of brain stimulation on brain networks during creative thinking and on creative performance have not been clarified. The present study was designed to examine the changes in functional connectivity (FC) and effective connectivity (EC) of the largescale brain network, and the ensuing changes in creative performance, induced by transcranial direct current stimulation (tDCS). Fourteen healthy male students underwent two tDCS sessions, one with actual stimulation and one with sham stimulation, on two separate days. Participants underwent tDCS (anode over the left dorsolateral prefrontal cortex, DLPFC; cathode over the right inferior parietal lobule, IPL) for 20 min. Before and after the tDCS session, electroencephalography signals were acquired from 32 electrodes over the whole head during the creative thinking task. On FC analysis, the delta band FC between the posterior cingulate cortex and IPL significantly increased only after real stimulation. We also found that the change of flexibility score was significantly correlated with the change in: (i) delta band FC between mPFC and left lateral temporal cortex (LTC) and (ii) alpha band FC between IPL and right LTC. On EC analysis, decreased flow within the DN (from left LTC to right IPL) was observed. Our results reveal that tDCS could affect brain networks, particularly the DN, during creative thinking and modulate key FC in the generation of flexible creative ideas.

tDCS Anodal Stimulation of the Right Dorsolateral Prefrontal Cortex Improves Creative Performance in Real-World Problem Solving

“…Few recent studies on the relationship between tDCS and creativity consistently found that the left DLPFC is connected to creative performance related to language reasoning, which proves the important role of the left DLPFC in the creative thinking process during language reasoning [ 21 , 24 , 46 , 47 , 48 ]. However, there is a lack of research on the role of the right DLPFC in creative thinking.…”

“…The participates were randomly assigned into two groups (18 people per group). According to the sample size calculation based on power analysis using G*Power version 3.1.9.7, in similar tDCS experiments [ 24 ], input-related parameters (effect size dz = 0.93, α error probability p = 0.05, power = 0.8) found that a sample size of 12 is sufficient to obtain reliable results. All participants were right-handed, native Chinese speakers with normal or corrected vision [ 25 ].…”

Influence of Creativity Stimulation on Brain Connectivity during Divergent Thinking Tasks

“…36,37 Previous studies have suggested that functional connectivity with the mPFC has shown significant relationship with divergent thinking which differs with individual creative abilities, 35,38 such as with lateral temporal cortex. 38,39 Psychophysiological interaction between mPFC and left IFG was also found to be positively correlated with creative use and creative metaphor generation tasks 40 which inferred that generation of creative ideas necessitates the making of remote semantic association and their conceptual integration. The present findings demonstrated causal connection from mPFC to bilateral IFG during the search and generation of alternative uses, regardless of individual DT ability.…”

Development of Low-Contact-Impedance Dry Electrodes for Electroencephalogram Signal Acquisition

“…Moreover, hybrid electrode systems that contain dry EEG electrodes and other types of electrodes have been developed. For example, dry EEG electrodes have been combined with transcranial directcurrent stimulation electrodes in a single headset [28]. With regard to the electrode shape and structure, electrodes made of stainless steel have a flat and round structure, whereas those made of gold alloy have a single-pin-based or multiple-pin-based structure that is fully rigid, spring-loaded, or placed in a rotating holder [29,30].…”