Abstract
BACKGROUND: Previous research has demonstrated a link between creative thinking and alpha oscillations, with individuals exhibiting stronger fronto-parietal alpha synchronization during creative tasks. Effective creative thinking is thought to rely on the coordinated activity of the default mode network (DMN) and the executive control network (ECN), particularly in the frontal and parieto-occipital regions, as reflected by variations in alpha oscillatory activity recorded via EEG. Prior studies have shown that transcranial alternating current stimulation (tACS) at the alpha frequency (α-tACS) can enhance DMN activity in the parieto-occipital cortex, and that 10 Hz tACS may increase both alpha power and creative performance. However, the precise effects of α-tACS on creative thinking remain to be fully elucidated. METHODS: To investigate the effects of α-tACS applied to the parieto-occipital region on creative thinking and its underlying cognitive neural mechanisms, we employed a within-participant design using EEG and the Alternative Uses Task (AUT). 28 participants completed two experimental sessions-one with sham stimulation and one with α-tACS-separated by a 24 ~ 48 h interval. In each session, participants performed the AUT immediately following stimulation. RESULTS: Behavioral results showed that participants receiving α-tACS exhibited significantly greater levels of novelty, flexibility, fluency, originality, and elaboration compared to the sham condition. Time-frequency analysis of EEG data further revealed that α-tACS significantly increased alpha power in the parieto-occipital regions relative to sham stimulation. CONCLUSIONS: These findings suggest that α-tACS applied to the parieto-occipital cortex, with an inter-session interval of 24 to 48 h, enhances creative thinking performance. This supports the potential of α-tACS as a neuromodulatory technique for facilitating creative cognitive processes.