Biomedical Engineering Research Division, University of Glasgow, Glasgow G12 8QQ, UK.
Medical Instrumentation Techniques Engineering Department, Northern Technical University, Mosul 41002, Iraq.
Sensors (Basel). 2022 Aug 23;22(17):6337. doi: 10.3390/s22176337.
The aim of this study was to differentiate the effects of spinal cord injury (SCI) and central neuropathic pain (CNP) on effective connectivity during motor imagery of legs, where CNP is typically experienced.
Multichannel EEG was recorded during motor imagery of the legs in 3 groups of people: able-bodied ( = 10), SCI with existing CNP ( = 10), and SCI with no CNP ( = 20). The last group was followed up for 6 months to check for the onset of CNP. Source reconstruction was performed to obtain cortical activity in 17 areas spanning sensorimotor regions and pain matrix. Effective connectivity was calculated using the directed transfer function in 4 frequency bands and compared between groups.
A total of 50% of the SCI group with no CNP developed CNP later. Statistically significant differences in effective connectivity were found between all groups. The differences between groups were not dependent on the frequency band. Outflows from the supplementary motor area were greater for the able-bodied group while the outflows from the secondary somatosensory cortex were greater for the SCI groups. The group with existing CNP showed the least differences from the able-bodied group, appearing to reverse the effects of SCI. The connectivities involving the pain matrix were different between able-bodied and SCI groups irrespective of CNP status, indicating their involvement in motor networks generally.
The study findings might help guide therapeutic interventions targeted at the brain for CNP alleviation as well as motor recovery post SCI.
本研究旨在区分脊髓损伤（SCI）和中枢神经性疼痛（CNP）对腿部运动想象时有效连通性的影响，因为 CNP 通常是在这种情况下出现的。
在 3 组人群中记录腿部运动想象时的多通道 EEG：健康人（n=10）、存在 CNP 的 SCI 患者（n=10）和没有 CNP 的 SCI 患者（n=20）。最后一组随访 6 个月以检查 CNP 的发病情况。进行源重建以获得跨越感觉运动区域和疼痛矩阵的 17 个区域的皮质活动。使用定向传递函数在 4 个频带中计算有效连通性，并在组间进行比较。
没有 CNP 的 SCI 组中有 50%的人后来出现了 CNP。所有组之间的有效连通性均存在统计学差异。组间差异不依赖于频带。健康人组的辅助运动区的输出更大，而 SCI 组的次级躯体感觉皮层的输出更大。存在 CNP 的组与健康人组的差异最小，似乎逆转了 SCI 的影响。无论 CNP 状态如何，涉及疼痛矩阵的连通性在健康人和 SCI 组之间是不同的，这表明它们通常参与运动网络。
该研究结果可能有助于指导针对 CNP 缓解和 SCI 后运动恢复的大脑靶向治疗干预。
