Tripod transcranial alternating current stimulation at 5-Hz to alleviate anxiety symptoms: a preliminary report

Abstract

ABSTRACTIntroductionOne of the most common applications of transcranial electrical stimulation (tES) at low current intensity is to induce a relaxed state or reduce anxiety. With technical advancement, different waveforms, montages, and parameters can be incorporated into the treatment regimen. We developed a novel protocol to treat individuals with anxiety disorders by transcranial alternating current stimulation (tACS).MethodsA total of 27 individuals with anxiety disorders underwent tACS treatment for 12 sessions, with each session lasting 25 minutes. tACS at 5 Hz was applied to F4 (1.0 mA), P4 (1.0 mA), and T8 (2.0 mA) EEG lead positions (tripod), with sinewave oscillation between T8 and F4/P4. We evaluated the primary and secondary outcomes using the Beck Anxiety Inventory (BAI) and neuropsychological assessments.ResultsOf the 27 patients, 19 (70.4%) experienced a reduction in symptom severity greater than 50%, with an average reduction of BAI 58.5%. All reported side effects were mild, with itching or tingling being the most common complaint. No significant differences were noted in attention, linguistic working memory, visuospatial working memory, or long-term memory in neuropsychological assessments.ConclusionThe results suggest the potential of this novel tripod tACS design as a rapid anxiety alleviator and the importance of a clinical trial to verify its efficacy.