Gholamali Nezhad Fatemeh, Martin Josh, Tassone Vanessa K, Swiderski Alyssa, Demchenko Ilya, Khan Somieya, Chaudhry Hamzah E, Palmisano Annalisa, Santarnecchi Emiliano, Bhat Venkat
Interventional Psychiatry Program, St. Michael's Hospital - Unity Health Toronto, Toronto, ON, Canada.
Institute of Medical Science, Temerty Faculty of Medicine, University of Toronto, Toronto, ON, Canada.
Front Psychiatry. 2024 Aug 14;15:1419243. doi: 10.3389/fpsyt.2024.1419243. eCollection 2024.
Transcranial alternating current stimulation (tACS) alters cortical excitability with low-intensity alternating current and thereby modulates aberrant brain oscillations. Despite the recent increase in studies investigating the feasibility and efficacy of tACS in treating neuropsychiatric disorders, its mechanisms, as well as optimal stimulation parameters, are not fully understood.
This systematic review aimed to compile human research on tACS for neuropsychiatric disorders to delineate typical treatment parameters for these conditions and evaluate its outcomes.
A search for published studies and unpublished registered clinical trials was conducted through OVID (MEDLINE, PsycINFO, and Embase), ClinicalTrials.gov, and the International Clinical Trials Registry Platform. Studies utilizing tACS to treat neuropsychiatric disorders in a clinical trial setting were included.
In total, 783 published studies and 373 clinical trials were screened; 53 published studies and 70 clinical trials were included. Published studies demonstrated a low risk of bias, as assessed by the Joanna Briggs Institute Critical Appraisal Tools. Neurocognitive, psychotic, and depressive disorders were the most common disorders treated with tACS. Both published studies (58.5%) and registered clinical trials (52%) most commonly utilized gamma frequency bands and tACS was typically administered at an intensity of 2 mA peak-to-peak, once daily for 20 or fewer sessions. Although the targeted brain locations and tACS montages varied across studies based on the outcome measures and specific pathophysiology of the disorders, the dorsolateral prefrontal cortex (DLPFC) was the most common target in both published studies (30.2%) and registered clinical trials (25.6%). Across studies that published results on tACS outcome measures, tACS resulted in enhanced symptoms and/or improvements in overall psychopathology for neurocognitive (all 11 studies), psychotic (11 out of 14 studies), and depressive (7 out of 8 studies) disorders. Additionally, 17 studies reported alterations in the power spectrum of the electroencephalogram around the entrained frequency band at the targeted locations following tACS.
Behavioral and cognitive symptoms have been positively impacted by tACS. The most consistent changes were reported in cognitive symptoms following gamma-tACS over the DLPFC. However, the paucity of neuroimaging studies for each neuropsychiatric condition highlights the necessity for replication studies employing biomarker- and mechanism-centric approaches.
经颅交流电刺激（tACS）通过低强度交流电改变皮质兴奋性，从而调节异常脑振荡。尽管最近对tACS治疗神经精神疾病的可行性和疗效的研究有所增加，但其机制以及最佳刺激参数尚未完全明确。
本系统评价旨在汇总关于tACS治疗神经精神疾病的人体研究，以确定这些疾病的典型治疗参数并评估其结果。
通过OVID（医学文献数据库、心理学文摘数据库和循证医学数据库）、ClinicalTrials.gov和国际临床试验注册平台检索已发表的研究和未发表的注册临床试验。纳入在临床试验环境中利用tACS治疗神经精神疾病的研究。
共筛选出783项已发表研究和373项临床试验；纳入53项已发表研究和70项临床试验。根据乔安娜·布里格斯研究所的批判性评价工具评估，已发表研究显示出较低的偏倚风险。神经认知障碍、精神病性障碍和抑郁障碍是tACS治疗最常见的疾病。已发表研究（58.5%）和注册临床试验（52%）最常使用γ频段，tACS通常以峰峰值2 mA的强度给药，每天一次，疗程为20次或更少。尽管根据疾病的结局指标和特定病理生理学，各研究的靶向脑区和tACS电极放置方式有所不同，但背外侧前额叶皮质（DLPFC）在已发表研究（30.2%）和注册临床试验（25.6%）中都是最常见的靶点。在发表了tACS结局指标结果的研究中，tACS使神经认知障碍（所有11项研究）、精神病性障碍（14项研究中的11项）和抑郁障碍（8项研究中的7项）的症状得到改善和/或整体精神病理学得到改善。此外，17项研究报告了tACS后靶向位置周围脑电频率带功率谱的改变。
tACS对行为和认知症状产生了积极影响。DLPFC区域γ-tACS后认知症状的变化最为一致。然而，针对每种神经精神疾病的神经影像学研究较少，这凸显了采用以生物标志物和机制为中心的方法进行重复研究的必要性。
