Vrana Andrea, Hotz-Boendermaker Sabina, Stämpfli Philipp, Hänggi Jürgen, Seifritz Erich, Humphreys B Kim, Meier Michael L
University Hospital of Balgrist, Zurich, Switzerland.
Department of Health Sciences and Technology, Human Movement Sciences, ETH Zurich, Switzerland.
PLoS One. 2015 Nov 16;10(11):e0142391. doi: 10.1371/journal.pone.0142391. eCollection 2015.
Chronic low back pain (chronic LBP) is both debilitating for patients but also a major burden on the health care system. Previous studies reported various maladaptive structural and functional changes among chronic LBP patients on spine- and supraspinal levels including behavioral alterations. However, evidence for cortical reorganization in the sensorimotor system of chronic LBP patients is scarce. Motor Imagery (MI) is suitable for investigating the cortical sensorimotor network as it serves as a proxy for motor execution. Our aim was to investigate differential MI-driven cortical processing in chronic LBP compared to healthy controls (HC) by means of functional magnetic resonance imaging (fMRI). Twenty-nine subjects (15 chronic LBP patients, 14 HC) were included in the current study. MI stimuli consisted of randomly presented video clips showing every-day activities involving different whole-body movements as well as walking on even ground and walking downstairs and upstairs. Guided by the video clips, subjects had to perform MI of these activities, subsequently rating the vividness of their MI performance. Brain activity analysis revealed that chronic LBP patients exhibited significantly reduced activity compared to HC subjects in MI-related brain regions, namely the left supplementary motor area and right superior temporal sulcus. Furthermore, psycho-physiological-interaction analysis yielded significantly enhanced functional connectivity (FC) between various MI-associated brain regions in chronic LBP patients indicating diffuse and non-specific changes in FC. Current results demonstrate initial findings about differences in MI-driven cortical processing in chronic LBP pointing towards reorganization processes in the sensorimotor network.
慢性下腰痛（chronic LBP）不仅会使患者身体衰弱，也是医疗保健系统的一大负担。先前的研究报告了慢性下腰痛患者在脊柱和脊髓上水平存在各种适应性不良的结构和功能变化，包括行为改变。然而，慢性下腰痛患者感觉运动系统中皮质重组的证据很少。运动想象（MI）适合于研究皮质感觉运动网络，因为它可作为运动执行的替代指标。我们的目的是通过功能磁共振成像（fMRI）研究慢性下腰痛患者与健康对照（HC）相比，MI驱动的皮质处理差异。本研究纳入了29名受试者（15名慢性下腰痛患者，14名HC）。MI刺激由随机呈现的视频片段组成，这些片段展示了涉及不同全身运动的日常活动，以及在平坦地面上行走、上下楼梯。在视频片段的引导下，受试者必须对这些活动进行运动想象，随后对其运动想象表现的生动程度进行评分。脑活动分析显示，与HC受试者相比，慢性下腰痛患者在与运动想象相关的脑区，即左侧辅助运动区和右侧颞上沟，活动明显减少。此外，心理生理交互作用分析显示，慢性下腰痛患者各种与运动想象相关的脑区之间的功能连接（FC）显著增强，表明FC存在弥漫性和非特异性变化。目前的结果表明了慢性下腰痛患者在运动想象驱动的皮质处理方面的差异的初步发现，指向感觉运动网络中的重组过程。
