Movement to Health (M2H) Laboratory, Euromov, Montpellier-1 University, Montpellier, France.
School of Exercise and Health Sciences, Edith Cowan University, Perth, Australia.
Adv Exp Med Biol. 2013;789:73-79. doi: 10.1007/978-1-4614-7411-1_11.
This study investigated whether manipulation of motor cortex excitability by transcranial direct current stimulation (tDCS) modulates neuromuscular fatigue and functional near-infrared spectroscopy (fNIRS)-derived prefrontal cortex (PFC) activation. Fifteen healthy men (27.7 ± 8.4 years) underwent anodal (2 mA, 10 min) and sham (2 mA, first 30 s only) tDCS delivered to the scalp over the right motor cortex. Subjects initially performed a baseline sustained submaximal (30 % maximal voluntary isometric contraction, MVC) isometric contraction task (SSIT) of the left elbow flexors until task failure, which was followed 50 min later by either an anodal or sham treatment condition, then a subsequent posttreatment SSIT. Endurance time (ET), torque integral (TI), and fNIRS-derived contralateral PFC oxygenated (O2Hb) and deoxygenated (HHb) hemoglobin concentration changes were determined at task failure. Results indicated that during the baseline and posttreatment SSIT, there were no significant differences in TI and ET, and increases in fNIRS-derived PFC activation at task failure were observed similarly regardless of the tDCS conditions. This suggests that the PFC neuronal activation to maintain muscle force production was not modulated by anodal tDCS.
本研究旨在探讨经颅直流电刺激（tDCS）对运动皮层兴奋性的调节是否会影响神经肌肉疲劳和功能近红外光谱（fNIRS）衍生的前额叶皮层（PFC）激活。15 名健康男性（27.7±8.4 岁）接受了头皮上右运动皮层的阳极（2 mA，10 分钟）和假阳极（2 mA，仅前 30 秒）tDCS。受试者最初进行了基线持续亚最大（30%最大自主等长收缩，MVC）等长收缩任务（SSIT），直到任务失败，然后在 50 分钟后进行阳极或假阳极处理，然后进行随后的治疗后 SSIT。在任务失败时，确定了耐力时间（ET）、扭矩积分（TI）和 fNIRS 衍生的对侧 PFC 氧合（O2Hb）和去氧（HHb）血红蛋白浓度变化。结果表明，在基线和治疗后 SSIT 期间，TI 和 ET 没有显著差异，并且无论 tDCS 条件如何，任务失败时 PFC 神经元激活以维持肌肉力量产生的增加是相似的。这表明阳极 tDCS 并未调节 PFC 神经元的激活以维持肌肉力量的产生。
