Schaechter Judith D, Moore Christopher I, Connell Brendan D, Rosen Bruce R, Dijkhuizen Rick M
MGH/MIT/HMS Athinoula A. Martinos Center for Biomedical Imaging Charlestown, Boston, USA.
Brain. 2006 Oct;129(Pt 10):2722-33. doi: 10.1093/brain/awl214. Epub 2006 Aug 18.
Animal studies have demonstrated that motor recovery after hemiparetic stroke is associated with functional and structural brain plasticity. While studies in stroke patients have revealed functional plasticity in sensorimotor cortical areas in association with motor recovery, corresponding structural plasticity has not been shown. We sought to test the hypothesis that chronic hemiparetic stroke patients exhibit structural plasticity in the same sensorimotor cortical areas that exhibit functional plasticity. Functional MRI during unilateral tactile stimulation and structural MRI was conducted in chronic stroke patients and normal subjects. Using recently developed computational methods for high-resolution analysis of MRI data, we evaluated for between-group differences in functional activation responses, and cortical thickness of areas that showed an enhanced activation response in the patients. We found a significant (P < 0.005) increase in the activation response in areas of the ventral postcentral gyrus (POG) in the patients relative to controls. These same ventral POG areas showed a significant (P < 0.05) increase in cortical thickness in the patients. Control cortical areas did not show a significant between-group difference in thickness or activation response. These results provide the first evidence of structural plasticity co-localized with areas exhibiting functional plasticity in the human brain after stroke.
动物研究表明，偏瘫性中风后的运动恢复与大脑的功能和结构可塑性有关。虽然对中风患者的研究揭示了感觉运动皮层区域的功能可塑性与运动恢复相关，但尚未发现相应的结构可塑性。我们试图验证这样一个假设：慢性偏瘫性中风患者在表现出功能可塑性的相同感觉运动皮层区域呈现出结构可塑性。对慢性中风患者和正常受试者进行了单侧触觉刺激期间的功能磁共振成像（fMRI）和结构磁共振成像（MRI）。使用最近开发的用于MRI数据高分辨率分析的计算方法，我们评估了功能激活反应的组间差异，以及患者中显示激活反应增强的区域的皮质厚度。我们发现，与对照组相比，患者腹侧中央后回（POG）区域的激活反应显著增加（P < 0.005）。这些相同的腹侧POG区域在患者中显示出皮质厚度显著增加（P < 0.05）。对照皮质区域在厚度或激活反应方面未显示出显著的组间差异。这些结果首次证明了中风后人类大脑中与表现出功能可塑性的区域共定位的结构可塑性。
