Applications of transcranial alternating current stimulation in psychological research

Abstract: Transcranial alternating current stimulation (tACS) is a non-invasive neuromodulation technique that modulates neural oscillations in specific brain regions by applying periodic, low-amplitude electrical currents at defined frequencies to the scalp, thereby altering cognitive functions or improving clinical symptoms. Since this technique was first applied this technique to human brain research in 2008, psychological researchers have utilized tACS to reveal causal relationships between distinct brain oscillations and specific cognitive activities. Firstly, we introduces the mechanisms by which tACS modulates neural oscillations. Secondly, we summarizes recent applications of tACS in modulating single-brain cognitive processes including perception, attention, motor control, learning and memory, emotion regulation, as well as its application in interpersonal social interactions. Future research should precisely control the phase relationship between applied tACS currents and endogenous brain oscillations, while considering individual differences in brain oscillations, to achieve accurate neural modulation with tACS and thus better elucidate the neural oscillatory mechanisms underlying various cognitive functions. Additionally, systematic evaluations of treatment protocols and the sustainability of therapeutic effects of tACS in clinical applications are needed to provide scientific guidance for clinical practice.