Effects of transcranial direct current stimulation and high-definition transcranial direct current stimula-tion on motor cortex excitability in healthy adults
10.3969/j.issn.1001-1242.2025.10.012
- VernacularTitle:经颅直流电刺激和高精度经颅直流电刺激对健康成年人运动皮层兴奋性的影响
- Author:
Yajuan LI
1
;
Shasha FAN
1
;
Bo ZENG
1
Author Information
1. 山西白求恩医院(山西医学科学院),山西医科大学第三医院;同济山西医院,山西省太原市,030032
- Publication Type:Journal Article
- Keywords:
transcranial direct current stimulation;
high-definition transcranial direct current stimulation;
transcra-nial magnetic stimulation;
motor evoked potential;
resting movement threshold;
central motor conduction time
- From:
Chinese Journal of Rehabilitation Medicine
2025;40(10):1534-1540
- CountryChina
- Language:Chinese
-
Abstract:
Objective:Transcranial direct current stimulation(tDCS),a non-invasive and safe neuromodulation technique,has been widely applied in stroke rehabilitation and motor function enhancement.However,differences in the ef-fects of conventional tDCS and high-definition tDCS(HD-tDCS)remain unclear.This study aims to compare the effects of tDCS and HD-tDCS on motor cortex excitability in healthy adults,providing evidence for the optimization of clinical neuromodulation strategies.Method:Forty healthy participants who met the inclusion criteria were enrolled and randomly assigned to two groups(group A and group B),with 20 participants in each group.A two-phase,two-treatment crossover de-sign was employed.In the first phase,participants in Group A received HD-tDCS with a center-anodal configu-ration over the motor cortex corresponding to the hemisphere with a higher resting motor threshold(RMT)de-termined by transcranial magnetic stimulation(TMS).The stimulation intensity was 1.5 mA and lasted for 20 minutes.After a 24-hour washout,the second phase involved anodal tDCS with identical stimulation parame-ters and location.In contrast,group B first received anodal tDCS followed by HD-tDCS after the washout pe-riod.Changes in motor evoked potential(MEP)of the bilateral motor cortices were assessed at multiple time points,including changes in bilateral RMT,the RMT difference(ΔRMT),and central motor conduction time(CMCT).Result:No significant differences were found between the two phases for any of the observed variables(P>0.05).Compared with baseline,both stimulation methods led to immediate and significant reductions in bilater-al RMT and ΔRMT,as well as shortened CMCT on the stimulated side(P<0.05).On stimulated-side,tDCS produced a more immediate reduction in RMT,while HD-tDCS showed a peak reduction at 30 minutes post-stimulation.In both cases,RMT gradually returned to baseline by 120 minutes.A significant difference in RMT changes between the two methods was observed after 30 minutes(P<0.05).On non-stimulated-side,a marked immediate increase was observed following tDCS,but subsequent trends were similar between the two methods,with no significant differences.Bilateral CMCT decreased after both types of stimulation,with no significant differences in changes over time between the two methods.Conclusion:tDCS has a more pronounced immediate effect on RMT modulation,while HD-tDCS exhibits more prominent delayed effects.