Key Laboratory of Molecular Imaging and Functional Imaging, Institute of Automation, Chinese Academy of Sciences, Beijing, China.
PLoS One. 2013 May 28;8(5):e64154. doi: 10.1371/journal.pone.0064154. Print 2013.
Previous studies have shown that motor recovery of stroke can be assessed by the cortical activity and the structural integrity of the corticospinal tract (CST), but little is known about the relation between the cortical activity and the structural integrity during motor recovery. In the present study, we investigated the changes in brain activities evoked by twenty days' functional electrical stimulation (FES) training in twelve sub-acute stroke patients with unilateral upper-limb disability. We compared cortex activity evoked by wrist movement of eleven stroke patients to that of eleven age-matched healthy subjects to figure out how cortex activity changed after stroke. We also measured the structural integrity represented by the fractional anisotropy (FA) asymmetry of the posterior limb of the internal capsule (PLIC) to find the relationship between the brain activity and the structure integrity. In our study, we found that patients with sub-acute stroke have shown greater activity in the contralesional primary motor cortex (M1) during the affected hand's movement compared with healthy group, while the activity in ipsilesional M1 was decreased after the therapy compared to that before therapy, and the contralesional non-primary motor cortex showed greater activity after therapy. At the baseline we found that the positive correlation between the FA asymmetry of PLIC and the contralesional non-primary motor cortex activity showed that the greater damaged CST, the greater contralesional non-primary motor cortex recruited. While the negative correlation between them after the FES training indicates that after recovery the non-primary motor cortex plays different role in different stroke phases. Our study demonstrates that functional organization of a residual distributed motor system is related to the degree of disruption to the CST, and the non-primary motor areas plays an important role in motor recovery.
先前的研究表明，皮质活动和皮质脊髓束（CST）的结构完整性可以评估中风后的运动恢复，但对于皮质活动与运动恢复过程中的结构完整性之间的关系知之甚少。在本研究中，我们调查了十二名亚急性中风单侧上肢残疾患者接受二十天功能性电刺激（FES）训练后大脑活动的变化。我们将十一名中风患者的腕部运动引起的皮层活动与十一名年龄匹配的健康受试者进行了比较，以了解中风后皮层活动如何变化。我们还测量了后内囊（PLIC）后肢的结构完整性表示的各向异性分数（FA）不对称性，以寻找大脑活动与结构完整性之间的关系。在我们的研究中，我们发现亚急性中风患者在受影响的手运动期间对侧初级运动皮层（M1）表现出更大的活动，而在治疗后对侧 M1 的活动比治疗前减少，对侧非初级运动皮层的活动增加。在基线时，我们发现PLIC 的 FA 不对称性与对侧非初级运动皮层活动之间存在正相关，表明 CST 受损越大，对侧非初级运动皮层的募集越大。而在 FES 训练后它们之间的负相关表明，恢复后非初级运动皮层在不同的中风阶段发挥不同的作用。我们的研究表明，残留分布式运动系统的功能组织与 CST 的破坏程度有关，而非初级运动区在运动恢复中起着重要作用。
