Suzuki Takako, Suzuki Makoto, Kanemura Naohiko, Hamaguchi Toyohiro
School of Health Sciences, Saitama Prefectural University, Saitama, Japan.
Department of Rehabilitation, Faculty of Health Sciences, Tokyo Kasei University, Saitama, Japan.
Front Integr Neurosci. 2019 Oct 29;13:63. doi: 10.3389/fnint.2019.00063. eCollection 2019.
This study investigated the corticospinal excitability of reciprocal muscles during tasks involving sensory difference between proprioceptive and visual inputs. Participants were instructed to relax their muscles and to observe a screen during vibratory stimulation. A video screen was placed on the board covering the right hand and forearm. Participants were randomly tested in four conditions: resting, control, static, and dynamic. The resting condition involved showing a black screen, the control condition, a mosaic patterned static videoclip; the static condition, a static videoclip of wrist flexion 0°; and the dynamic condition, a videoclip that corresponded to each participant's closely-matched illusory wrist flexion angle and speed by vibration. Vibratory stimulation (frequency 80 Hz and duration 4 s) was applied to the distal tendon of the dominant right extensor carpi radialis (ECR) using a tendon vibrator in the control, static, and dynamic conditions. Four seconds after the vibratory stimulation (end of vibration), the primary motor cortex at the midpoint between the centers of gravity of the flexor carpi radialis (FCR) and ECR muscles was stimulated by transcranial magnetic stimulation (TMS). The ECR motor evoked potential (MEP) amplitudes significantly increased in the control condition compared to the resting condition, whereas the FCR MEP amplitudes did not change between the resting and control conditions. In addition, the ECR MEP amplitudes significantly increased in the static condition compared to the dynamic condition. However, the FCR MEP amplitudes significantly increased in the dynamic condition compared to the static condition. These results imply that the difference between visuo-proprioceptive information had an effect on corticospinal excitability for the muscle. In conclusion, we found that proprioceptive and visual information differentially altered the corticospinal excitability of reciprocal muscles.
本研究调查了在涉及本体感觉和视觉输入之间感觉差异的任务中，相互拮抗肌的皮质脊髓兴奋性。参与者被要求放松肌肉，并在振动刺激期间观察屏幕。在覆盖右手和前臂的板上放置了一个视频屏幕。参与者在四种条件下进行随机测试：静息、对照、静态和动态。静息条件是显示黑屏，对照条件是播放马赛克图案的静态视频剪辑；静态条件是手腕屈曲0°的静态视频剪辑；动态条件是与每个参与者通过振动紧密匹配的虚幻手腕屈曲角度和速度相对应的视频剪辑。在对照、静态和动态条件下，使用肌腱振动器对优势右侧桡侧腕伸肌（ECR）的远端肌腱施加振动刺激（频率80Hz，持续时间4s）。振动刺激结束后4秒，通过经颅磁刺激（TMS）刺激桡侧腕屈肌（FCR）和ECR肌肉重心中点处的初级运动皮层。与静息条件相比，对照条件下ECR运动诱发电位（MEP）幅度显著增加，而静息和对照条件下FCR MEP幅度没有变化。此外，与动态条件相比，静态条件下ECR MEP幅度显著增加。然而，与静态条件相比，动态条件下FCR MEP幅度显著增加。这些结果表明，视觉-本体感觉信息之间的差异对肌肉的皮质脊髓兴奋性有影响。总之，我们发现本体感觉和视觉信息对相互拮抗肌的皮质脊髓兴奋性有不同的影响。
