切咬训练对咬肌皮质控制区域兴奋性的影响

Evaluation of neuroplastic changes in corticomotor control of masseter muscles after biting training

目的探究5天技能性切咬训练能否引起咬肌运动皮质控制区域的兴奋性变化。方法 对12名健康受试者进行5天×1h的技能性切咬训练,在第1天及第5天训练前后,评估受试者的技能掌握情况。利用导航经颅磁刺激技术,检测受试者右侧咬肌及第一指骨间肌(对照组)的皮质控制区域运动诱发电位,评估其兴奋性变化。结果 5天切咬训练中,受试者对技能训练的掌握程度逐渐增加( P <0.001);训练前后,咬肌皮质控制区域出现兴奋性增加( P <0.001),而第一指骨间肌的皮质控制区域兴奋性无明显变化( P =0.725)。结论 5天技能性切咬训练引起下颌运动的精细调整,诱发咬肌皮质控制区域特异性兴奋性变化,这可能与神经系统对环境的适应性改变有关。

Objective To evaluate the effect of 5-days biting training on corticomotor excitability of masseter muscles. Methods A total of 12 subjects were enrolled in a skilled biting training for 1 hour on 5 consecutive days. Task performance was recorded each day to evaluate the learning process in the training. The motor evoked potentials were recorded by transcranial magnetic stimulation in the masseter and the first dorsal interosseous muscles (as control) at four time periods, pre-task day 1 (baseline), post-task day 1, pre-task day 5, and post-task day 5. Results The result showed a significant increase in the performance during the training( P <0.001) and excitability of corticomotor control in masseter muscles after the training( P <0.001), whereas corticomotor control in FDI did not change among the four periods( P =0.725). Conclusion A 5-day biting training was effective to induce changes in the corticomotor excitability of masseter muscles and caused fine adjustment and adaptation of jaw movements. It may be related to physiological basis of human adaptations to the environment changes.