Simis Marcel, Adeyemo Bamidele O, Medeiros Liciane F, Miraval Forella, Gagliardi Rubens J, Fregni Felipe
aDepartment of Physical Medicine and Rehabilitation, Harvard Medical School, Boston, Massachusetts bDepartment of Physical Medicine and Rehabilitation, Emory University cDepartment of Physical Medicine and Rehabilitation, Marcus Stroke Science Center, Grady Hospital, Atlanta, Georgia, USA dDepartment of Neurology, Santa Casa de São Paulo Medical School, São Paulo ePost-graduation Program, Biological Sciences, Universidade Federal do Rio Grande do Sul (UFRGS), Porto Alegre, RS, Brazil fInstitute of Physical Medicine and Rehabilitation, Clinics Hospital of the University of Sao Paulo Medical School, Brazil.
Neuroreport. 2013 Dec 4;24(17):973-5. doi: 10.1097/WNR.0000000000000021.
The aim of this study was to test and compare the effects of a within-subject design of repetitive transcranial magnetic stimulation (rTMS) [coupled with sham transcranial direct current stimulation (tDCS)] and tDCS (coupled with sham rTMS) on the motor cortex excitability and also compare the results against sham tDCS/sham rTMS. We conducted a double-blinded, randomized, sham-controlled, cross-over trial. Eleven right-handed, healthy individuals (five women, mean age: 39.8 years, SD 13.4) received the three interventions (cross-over design) in a randomized order: (a) high-frequency (HF) rTMS (+sham tDCS), (b) anodal tDCS (+sham rTMS), and (c) sham stimulation (sham rTMS+sham tDCS). Cortical excitability measurements [motor threshold, motor evoked potential (MEP), intracortical facilitation and inhibition, and transcallosal inhibition] and motor behavioral assessments were used as outcome measures. Between-group analysis of variance showed that MEP amplitude after HF rTMS was significantly higher than MEP amplitude after anodal tDCS (P=0.001). Post-hoc analysis showed a significant increase in MEP amplitude after HF rTMS (25.3%, P=0.036) and a significant decrease in MEP amplitude after anodal tDCS (-32.7%, P=0.001). There was a similar increase in motor function as indexed by Jebsen-Taylor Hand Function Test in the two active groups compared with sham stimulation. In conclusion, here, we showed that although both techniques induced similar motor gains, they induce opposing results in cortical excitability. HF rTMS is associated with an increase in corticospinal excitability, whereas 20 min of tDCS induces the opposite effect. We discuss potential implications of these results to future clinical experiments using rTMS or tDCS for motor function enhancement.
本研究的目的是测试并比较重复经颅磁刺激（rTMS）[联合伪经颅直流电刺激（tDCS）]的受试者内设计与tDCS（联合伪rTMS）对运动皮层兴奋性的影响，并将结果与伪tDCS/伪rTMS进行比较。我们进行了一项双盲、随机、伪对照、交叉试验。11名右利手健康个体（5名女性，平均年龄：39.8岁，标准差13.4）以随机顺序接受三种干预（交叉设计）：（a）高频（HF）rTMS（+伪tDCS），（b）阳极tDCS（+伪rTMS），以及（c）伪刺激（伪rTMS + 伪tDCS）。皮层兴奋性测量[运动阈值、运动诱发电位（MEP）、皮质内易化和抑制以及胼胝体抑制]和运动行为评估用作结果指标。组间方差分析表明，HF rTMS后的MEP波幅显著高于阳极tDCS后的MEP波幅（P = 0.001）。事后分析表明，HF rTMS后MEP波幅显著增加（25.3%，P = 0.036），阳极tDCS后MEP波幅显著降低（-32.7%，P = 0.001）。与伪刺激相比，两个活跃组中由Jebsen - Taylor手功能测试所索引的运动功能有类似增加。总之，我们在此表明，尽管两种技术都诱导了类似的运动改善，但它们在皮层兴奋性方面诱导出相反的结果。HF rTMS与皮质脊髓兴奋性增加相关，而20分钟的tDCS则诱导相反的效果。我们讨论了这些结果对未来使用rTMS或tDCS增强运动功能的临床实验的潜在影响。
