Knikou Maria
The Graduate Center, City University of New York, New York, New York, United States of America; Departments of Physical Therapy & Neuroscience, College of Staten Island/CUNY, Staten Island, New York, United States of America; Sensory Motor Performance Program, Rehabilitation Institute of Chicago, Chicago, Illinois, United States of America; Department of Physical Medicine and Rehabilitation, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America.
PLoS One. 2014 Jul 9;9(7):e102313. doi: 10.1371/journal.pone.0102313. eCollection 2014.
The objective of this study was to assess changes in corticospinal excitability and spinal output following noninvasive transpinal and transcortical stimulation in humans. The size of the motor evoked potentials (MEPs), induced by transcranial magnetic stimulation (TMS) and recorded from the right plantar flexor and extensor muscles, was assessed following transcutaneous electric stimulation of the spine (tsESS) over the thoracolumbar region at conditioning-test (C-T) intervals that ranged from negative 50 to positive 50 ms. The size of the transpinal evoked potentials (TEPs), induced by tsESS and recorded from the right and left plantar flexor and extensor muscles, was assessed following TMS over the left primary motor cortex at 0.7 and at 1.1× MEP resting threshold at C-T intervals that ranged from negative 50 to positive 50 ms. The recruitment curves of MEPs and TEPs had a similar shape, and statistically significant differences between the sigmoid function parameters of MEPs and TEPs were not found. Anodal tsESS resulted in early MEP depression followed by long-latency MEP facilitation of both ankle plantar flexors and extensors. TEPs of ankle plantar flexors and extensors were increased regardless TMS intensity level. Subthreshold and suprathreshold TMS induced short-latency TEP facilitation that was larger in the TEPs ipsilateral to TMS. Noninvasive transpinal stimulation affected ipsilateral and contralateral actions of corticospinal neurons, while corticocortical and corticospinal descending volleys increased TEPs in both limbs. Transpinal and transcortical stimulation is a noninvasive neuromodulation method that alters corticospinal excitability and increases motor output of multiple spinal segments in humans.
本研究的目的是评估人类在接受非侵入性经脊髓和经皮质刺激后皮质脊髓兴奋性和脊髓输出的变化。在胸腰段区域经皮电刺激脊柱（tsESS）后，以-50至50毫秒的条件-测试（C-T）间隔，评估经颅磁刺激（TMS）诱发并从右足底屈肌和伸肌记录的运动诱发电位（MEP）的大小。在以-50至50毫秒的C-T间隔，于左侧初级运动皮层施加TMS，强度分别为0.7和1.1×MEP静息阈值后，评估tsESS诱发并从左右足底屈肌和伸肌记录的经脊髓诱发电位（TEP）的大小。MEP和TEP的募集曲线形状相似，未发现MEP和TEP的S形函数参数之间存在统计学显著差异。阳极tsESS导致早期MEP抑制，随后是双踝屈肌和伸肌的长潜伏期MEP易化。无论TMS强度水平如何，踝屈肌和伸肌的TEP均增加。阈下和阈上TMS诱发短潜伏期TEP易化，在TMS同侧的TEP中更大。非侵入性经脊髓刺激影响皮质脊髓神经元的同侧和对侧作用，而皮质皮质和皮质脊髓下行冲动增加了双下肢的TEP。经脊髓和经皮质刺激是一种非侵入性神经调节方法，可改变皮质脊髓兴奋性并增加人类多个脊髓节段的运动输出。
