功能磁共振成像仪评估运动疲劳后大脑皮质的激活状态

Evaluation of Activation State of Cerebral Cortex After Exercise Fatigue by Functional Magnetic Resonance Imaging

目的本文旨在探讨运动疲劳后大脑各功能区皮质的激活状态变化,及早了解中枢性运动疲劳的机制。方法收集32例健康受试者的资料,分为右利手组与左利手组,并设计了功率自行车骑行和双手/单手握拳的运动方案进行试验研究,同时给予功能磁共振成像检查。结果成像结果显示双手运动时,右利手被试者右手对应的脑左侧M1区ω_(1)值高于左手对应的脑右侧M1区ω_(1)值,右手运动疲劳后,其激活的脑左侧M1区ω_(1)值明显高于左手运动激活的脑右侧M1区ω_(1)值。双手运动时其左半球的ω_(1)值低于右手运动的M1区ω_(1)值,ω2的检测结果同上。左利手被试者的试验结果与之对称。在安静状态时,左侧基底神经节区的Cho/Cr为1.16±0.53;运动疲劳后则为0.71±0.52,出现明显下降,差异具有统计学意义(P<0.05)。安静状态时,左侧基底神经节区NAA/Cr为1.95±0.17,运动力竭后则为2.81±1.88,出现了显著上升,差异具有统计学意义(P<0.05)。结论利手相比非利手具有更长的神经簇时间响应,标准偏差也更大。而运动疲劳后左侧基底节代谢物Cho/Cr下降则是由运动性疲劳限制引起的,运动力竭后左侧基底节代谢物NAA/Cr上升则是运动性力竭的限制因素。总之,使用功能磁共振成像仪评估运动疲劳后大脑皮质的激活状态对神经科学和运动医学研究具有重要的价值。

Objective To explore the changes of activation state of cortex in various functional areas of brain after exercise fatigue,and understand the mechanism of central exercise fatigue as soon as possible.Methods A total of 32 healthy subjects were collected and divided into right-handed group and left-handed group.The exercise schemes of power bicycle riding and two hands/one hand fist clenching were designed for experimental research,functional magnetic resonance imaging(fMRI)was performed at the same time.Results The results showed that when both hands were moving at the same time,theω_(1) of the left M1 area corresponding to the right hand was higher than that of the right M1 area corresponding to the left hand.When the right hand reached exercise fatigue,theω_(1) of left M1 area activated by the right hand was significantly higher than theω_(1) of right M1 area activated by the left hand.When both hands were moving,theω_(1) value of the left hemisphere was lower than that of the M1 region of the right hand movement,and the result ofω2 was the same as above.The experimental results of left hands were symmetrical.The Cho/Cr ratio in the left basal ganglia was 1.16±0.53 at rest,after exercise fatigue,it was 0.71±0.52,the difference was statistically significant(P<0.05).The NAA/Cr ratio in the left basal ganglia was 1.95±0.17 at rest and 2.81±1.88 after exhaustive exercise,showing a significant increase(P<0.05).Conclusion The handedness has a longer cluster time response and a larger standard deviation than the non-handedness.The decrease of Cho/Cr ratio in left basal ganglia after exercise fatigue was caused by exercise fatigue limitation,and the increase of NAA/Cr ratio in left basal ganglia after exercise exhaustion was a limiting factor of exercise exhaustion.In short,using fMRI to evaluate the activation of cerebral cortex after exercise fatigue is of great value to the research of neuroscience and sports medicine.