前臂截肢者残肢运动时的脑源特征:基于标准化低分辨率脑电磁断层扫描成像技术

Brain sources characteristics during movement of residual limbs in forearm amputees based on standard low res‐olution brain electromagnetic tomography technology

目的 采用标准化低分辨率脑电磁断层扫描成像(sLORETA)技术观察单侧前臂截肢者残肢运动时大脑神经元电活动特征,进而阐明截肢对人体大脑可塑性的影响。方法 2019年6月至9月,选取9例右侧前臂截肢者(截肢组)和15例健全人(健全组)作为测试对象。采用便携式脑电系统分别采集两组双侧上肢在进行直臂屈伸运动时的脑电信号。比较两组在运动执行阶段时β频段(13~30 Hz)脑电信号的sLORETA脑源差异。结果 截肢组健肢执行运动任务时与健全组同侧运动时相比,大部分脑区激活的像素数量无显著性差异(|t|<2.023, P> 0.05);残肢执行运动任务时,大脑激活最多的脑区为BA7,其次是额叶BA6和BA10;位于大脑枕叶的BA18、BA19区激活的像素数目高于健全组(|t|> 2.782, P <0.05)。与健全组相比,残肢运动时激活的电流密度值更低(|t|> 2.012, P <0.05),主要位于额叶皮质的BA8、BA9、BA10、BA11、BA45、BA46、BA47区以及顶叶的BA7、BA13、BA21、BA22区,但在枕叶皮质的BA17、BA19区,其激活的电流密度值更大(|t|> 2.199, P <0.05)。结论 截肢者健肢执行上肢前臂屈伸运动时与健全人执行同一动作时的脑源激活模式相似,但其残肢在执行运动时,脑激活区域有向大脑枕区移动的特征。

Objective To observe electroencephalography(EEG)characteristics during movement of residual limbs in forearm am‐putees using standard low resolution brain electromagnetic tomography(sLORETA)technology.Methods From June to September,2019,nine right forearm amputees(amputee group)and 15 normal healthy subjects(control group)were selected.EEG signals were recorded as finishing a straight arm flexion and extension move‐ment task of the left and right upper limbs,and theβrhythm(13 to 30 Hz)of EEG during motor execution was analyzed with sLORETA.Results The distribution of brain activation was almost the same as the movement of ipsilateral limbs in the control group when the intact limb of amputees moved(|t|<2.023,P>0.05).During the stumps moving,activated vox‐els was the most in BA7,followed by BA6 and BA10 in the frontal lobe,while the number of activated voxels in the BA18 and BA19 of the occipital lobe was significantly higher than those in the normal group(|t|>2.782,P<0.05);while the normalized current density of activation was lower than that in the control group,locating in the BA8,BA9,BA10,BA11,BA45,BA46 and BA47 of the frontal cortex,and in the BA7,BA13,BA21 and BA22 of the parietal cortex(|t|>2.012,P<0.05),however,it was stronger in the BA17 and BA19 of occipital cortex(|t|>2.199,P<0.05).Conclusion The brain activation of the amputee is similar to the healthy subjects when they moving the intact limb.However,during the movement of the stump,the activated brain regions are moving toward the posterior occipi‐tal.