Abstract：
Paired corticomotoneuronal stimulation (or electrical PCMS: ePCMS) is the repetitive pairing of an electrical stimulus to a nerve with a transcranial magnetic stimulation of the primary motor cortex (TMS-of-M1) to noninvasively influence spinal plasticity. We compared ePCMS with the new painless PCMS protocol pairing a magnetic stimulus to the nerve with TMS-of-M1 (mPCMS) in the preactivated tibial anterior muscle (TA). Sixteen healthy adults participated in two sessions (mPCMS, ePCMS), each with 180 pairs of [low-intensity TMS-of-M1 + nerve stimulation] at 0.2 Hz. TA motor-evoked potentials (MEP) to single-pulse TMS at pre-PCMS, immediately and 30 min after PCMS, were cluster-analyzed to discriminate responders and non-responders. Paired-pulse TMS-of-M1 and F-waves were also tested and BDNF polymorphism influence was explored. Both PCMS protocols significantly increased MEP amplitudes (n = 9 responders each), but the time-course differed with mPCMS inducing larger MEP increase over time. The number of BDNF-methionine carriers tended to be larger than Val66Val in mPCMS and the reverse in ePCMS, thus warranting further investigations. The MEP changes of the preactivated TA likely occurred at the pre-motoneuronal level and larger mPCMS after-effects over time may be related to the afferents recruited. mPCMS seems relevant to be tested in future studies as a painless noninvasive approach to induce sustained pre-motoneuronal plasticity in spinal cord injury.
摘要：
配对的皮质神经元刺激（或电PCMS：ePCMS）是电刺激与神经的重复配对，对主运动皮层（TMS-of-M1）进行经颅磁刺激，以无创地影响脊柱可塑性。我们将ePCMS与新的无痛PCMS协议进行了比较，该协议在预激活的胫骨前肌（TA）中将磁刺激与M1的TMS-of-M1（mPCMS）配对。16名健康成年人参加了两次会议(mPCMS，ePCMS),每个都有180对0.2Hz的[低强度TMS-of-M1+神经刺激]。在pre-PCMS的单脉冲TMS的TA运动诱发电位（MEP），立即和PCMS后30分钟，进行聚类分析，以区分应答者和非应答者。还测试了成对脉冲TMS-of-M1和F波，并探索了BDNF多态性的影响。两种PCMS协议均显着增加了MEP幅度（每个n=9个响应者），但随着时间的推移，mPCMS诱导更大的MEP增加的时程有所不同。在mPCMS中BDNF-蛋氨酸载体的数量倾向于大于Val66Val，而在ePCMS中相反，因此需要进一步调查。预激活的TA的MEP变化可能发生在运动神经元前水平，并且随着时间的推移，更大的mPCMS后遗症可能与招募的传入有关。mPCMS似乎可以在未来的研究中进行测试，作为一种无痛的非侵入性方法，可以在脊髓损伤中诱导持续的运动神经元前可塑性。
