Frieske Joana, Van Hoornweder Sybren, Nuyts Marten, Verstraelen Stefanie, Swinnen Stephan P, Meesen Raf L J
REVAL - Rehabilitation Research Center, Faculty of Rehabilitation Sciences, University of Hasselt - Campus Diepenbeek, Wetenschapspark 7, Diepenbeek, B-3590, Belgium.
Movement Control and Neuroplasticity Research Group, Department of Movement Sciences, Group Biomedical Sciences, KU Leuven, Leuven, Belgium.
Sci Rep. 2024 Dec 5;14(1):30324. doi: 10.1038/s41598-024-81399-7.
Theta burst stimulation (TBS) can modulate cortical excitability but suffers from high inter-subject variability. Modified TBS frequency patterns (30 Hz) showed consistent inhibitory aftereffects, but further research into the time course of these effects is needed. This study aimed to investigate the efficacy of a 30 Hz continuous TBS (cTBS) protocol. Participants (n = 20) underwent an experimental session (real cTBS) and a control session (sham cTBS). To assess cortical excitability, Transcranial Magnetic Stimulation was applied over the primary motor cortex before cTBS, and at five timepoints after cTBS. Percentage change (PC) to baseline was analysed using a Linear Mixed Model. No difference in PC was found between real and sham cTBS (p = 0.696). Our results demonstrate a significant increase in PC over time (p = 0.006) at 30, (p = 0.01), 45 (p = 0.027), and 55 min (p = 0.024) post cTBS, irrespective of condition. Secondary analysis dividing the sample into responders and paradox-responders showed no significant predictors for cTBS responsiveness. We could not replicate previously reported suppressive effects of 30 Hz cTBS. Increases in MEP amplitudes over a 60-minute time window were independent of stimulation condition and marked by high inter-subject variability. Validations of modified TBS protocols are further needed to replicate findings and understand mechanisms underlying individuals' responsiveness.
theta爆发刺激（TBS）可调节皮层兴奋性，但个体间差异较大。改良的TBS频率模式（30Hz）显示出持续的抑制后效应，但需要对这些效应的时间进程进行进一步研究。本研究旨在探讨30Hz连续TBS（cTBS）方案的疗效。参与者（n = 20）接受了一个实验疗程（真实cTBS）和一个对照疗程（假cTBS）。为了评估皮层兴奋性，在cTBS之前以及cTBS之后的五个时间点，对初级运动皮层进行经颅磁刺激。使用线性混合模型分析相对于基线的百分比变化（PC）。在真实cTBS和假cTBS之间未发现PC有差异（p = 0.696）。我们的结果表明，无论何种情况，在cTBS后30分钟（p = 0.006）、45分钟（p = 0.01）、55分钟（p = 0.027）和60分钟（p = 0.024）时，PC随时间显著增加。将样本分为反应者和反常反应者的二次分析显示，没有显著的cTBS反应性预测指标。我们无法重复先前报道的30Hz cTBS的抑制作用。在60分钟时间窗口内运动诱发电位（MEP）幅度的增加与刺激条件无关，且个体间差异较大。进一步需要对改良的TBS方案进行验证，以重复研究结果并了解个体反应性的潜在机制。
