Lefebvre Richard, Pépin André, Louis Pierre-Félix, Boucher Jean P
Département de kinanthropologie, Université du Québec à Montréal, Canada.
J Manipulative Physiol Ther. 2004 Feb;27(2):97-102. doi: 10.1016/j.jmpt.2003.12.004.
Motor evoked potentials (MEPs) obtained from magnetic stimulation allow the measurement of the excitability of motor nerve cells. Although this technique is becoming widely used, its reliability has yet to be established.
To determine the reliability of MEPs and evaluate their stability.
Subjects received magnetic stimulation at 3 different sites: cranial, cervical, and peripheral. Three stimulations were given at each site. Stimulations were given under 4 conditions: eyes open or closed and with or without controlled mental activity.
The study was performed in a research laboratory setting.
Nine healthy subjects (mean age = 21 years +/- 0.9), asymptomatic of any neural or musculoskeletal dysfunctions.
Normalized peak-to-peak amplitude of MEPs at the opponens pollicis muscle.
Intraclass correlations were high for all conditions (R > 0.90). The amplitude of the MEPs elicited from the transcranial site during the controlled mental activity condition was increased by 26.6% (P =.017). No other significant differences (P >.05) were obtained among the other conditions.
Intraclass correlation results reveal that MEP measurements are highly reliable in a controlled environment. The increase of MEPs during the controlled mental activity condition could be attributed to an elevation of neural activity of different nonmotor areas of the brain increasing corticospinal excitability.
通过磁刺激获得的运动诱发电位（MEP）可用于测量运动神经细胞的兴奋性。尽管该技术正被广泛应用，但其可靠性尚未确立。
确定MEP的可靠性并评估其稳定性。
受试者在3个不同部位接受磁刺激：头颅部、颈部和外周。每个部位给予3次刺激。刺激在4种条件下进行：睁眼或闭眼以及有无控制性思维活动。
研究在研究实验室环境中进行。
9名健康受试者（平均年龄 = 21岁±0.9），无任何神经或肌肉骨骼功能障碍症状。
拇对掌肌处MEP的标准化峰峰值幅度。
所有条件下组内相关性均较高（R > 0.90）。在控制性思维活动条件下，经颅部位引出的MEP幅度增加了26.6%（P = 0.017）。其他条件之间未获得其他显著差异（P > 0.05）。
组内相关性结果表明，在可控环境中MEP测量具有高度可靠性。在控制性思维活动条件下MEP的增加可能归因于大脑不同非运动区域神经活动的增强，从而增加了皮质脊髓兴奋性。
