Suppression of corticospinal excitability during negative motor imagery.
Suppression of corticospinal excitability during negative motor imagery.
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负性运动想象期间皮质脊髓兴奋性的抑制。
DOI：
10.1152/jn.00206.2003
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发表时间：
2003
影响因子：
2.5
通讯作者：
Hallett,Mark
中科院分区：
文献类型：
--
作者：
Sohn,YoungH;Dang,Nguyet;Hallett,Mark
为了探讨消极运动想象对皮质脊髓兴奋性的影响，我们在7名健康受试者中进行了经颅磁刺激（TMS）研究。受试者被要求想象抑制TMS诱导的抽搐运动，他们的非优势左手，试图增加放松量后，收到一个听觉NoGo线索（消极的运动想象），但想象挤压手后，去提示（积极的运动想象）。单脉冲和双脉冲TMS在Go或NoGo提示后2秒触发。记录左手第一骨间背侧肌（FDI）、拇短展肌（APB）和小指展肌（ADM）的运动诱发电位（MEP）。在负性运动想象和对照条件下，分别采用阈下条件刺激（刺激间隔为2 ms（短皮层内抑制）和15 ms（皮层内易化））和阈上条件刺激（刺激间隔为80 ms（长皮层内抑制））进行双脉冲TMS。与控制状态（无想象）相比，FDI（而不是APB和ADM）的MEP幅度在负性运动想象中被显著抑制，但在正性运动想象中，所有三块肌肉的MEP幅度均无变化。F-波反应（幅度和持久性）是不变的，在消极和积极的运动想象。在负性运动想象过程中，静息运动阈值显著增加，但短、长皮层内抑制和皮层内易化没有变化。目前的结果表明，兴奋性皮质脊髓驱动抑制在想象抑制运动。
To investigate the effect of negative motor imagery on corticospinal excitability, we performed transcranial magnetic stimulation (TMS) studies in seven healthy subjects during imagination of suppressing movements. Subjects were asked to imagine suppression of TMS-induced twitching movement of their nondominant left hands by attempting to increase the amount of relaxation after receiving an auditory NoGo cue (negative motor imagery), but to imagine squeezing hands after a Go cue (positive motor imagery). Single- and paired-pulse TMS were triggered at 2 s after Go or NoGo cues. Motor-evoked potentials (MEPs) were recorded in the first dorsal interosseus (FDI), abductor pollicis brevis (APB), and abductor digiti minimi (ADM) muscles of the left hand. Paired-pulse TMS with subthreshold conditioning stimuli at interstimulus intervals of 2 (short intracortical inhibition) and 15 ms (intracortical facilitation) and that with suprathreshold conditioning stimuli at interstimulus interval of 80 ms (long intracortical inhibition) were performed in both negative motor imagery and control conditions. Compared with the control state (no imagination), MEP amplitudes of FDI (but not APB and ADM) were significantly suppressed in negative motor imagery, but those from all three muscles were unchanged during positive motor imagery. F-wave responses (amplitudes and persistence) were unchanged during both negative and positive motor imagery. During negative motor imagery, resting motor threshold was significantly increased, but short and long intracortical inhibition and intracortical facilitation were unchanged. The present results demonstrate that excitatory corticospinal drive is suppressed during imagination of suppressing movements.