Effects of different frequencies of transcranial alternating current stimulation on emotion and emotion regulation.

Emotion regulation is crucial in daily life, and transcranial alternating current stimulation (tACS) has the potential to improve it by modulating neural oscillations. In this study, 101 healthy adults were randomized into four groups: frontal theta tACS, frontal alpha tACS, parieto-occipital alpha tACS, and sham control. Participants completed emotion regulation and facial Stroop tasks during stimulation, with emotional states assessed using the Positive and Negative Affect Scale (PANAS) and the Profile of Mood States-Short Form (POMS-SF) before and after stimulation. Physiological signals were also recorded during the stimulation. Repeated measures ANOVA analyzes were used for pre/post scale scores, task performance and physiological features. Results indicated that frontal theta tACS reduced negative emotions and improved reappraisal ability, whereas parieto-occipital alpha tACS showed comparable but non-significant effect. In contrast, frontal alpha tACS increased negative emotions and reaction times to disgust faces. These findings suggest that frontal theta tACS is a promising protocol for improving emotion regulation, and tACS may serve as a valuable tool for exploring neural mechanisms underlying emotional disorders.

Supplementary information: The online version contains supplementary material available at 10.1007/s11571-025-10338-7.