Frackowiak R S, Weiller C, Chollet F
MRC Cyclotron Unit, Hammersmith Hospital, London, UK.
Ciba Found Symp. 1991;163:235-44; discussion 244-9. doi: 10.1002/9780470514184.ch14.
The functional neuroanatomical basis for recovery from ischaemic brain injury is not known. We have used positron emission tomography (PET) to study changes in the functional organization of the brain in patients recovering from striatocapsular motor strokes. Significant changes in regional cerebral blood flow (rCBF) were found during repetitive sequential opposition movements of the fingers in normal subjects and in patients with recovery from motor deficits. There was a difference in the pattern of cerebral activation when patients performed the motor task with the unaffected hand (when the activation was lateralized to contralateral sensorimotor and premotor cortex and ipsilateral cerebellum) and when the task was performed with the recovered, previously plegic hand (when the activation was bilateral and involved novel areas of cortex, especially area 40). Comparisons of rCBF maps at rest in the patient group and in normal subjects showed areas with significantly decreased rCBF in the patients (contralateral to the plegic hand in the basal ganglia, thalamus, insular cortex, brainstem and ipsilateral cerebellum), which reflected the distribution of dysfunction caused by the ischaemic lesions. A significantly increased activation over and above that in normal subjects was found in patients during movement of the recovered fingers in ipsilateral premotor cortex and bilateral frontal opercular/insular regions and area 40, the ipsilateral basal ganglia (the ischaemic lesion lying contralaterally) and the contralateral cerebellum. We postulate that these findings may be explained by the generation of movements by pathways that are different from those that normal subjects use to perform what are ordinarily fairly simple, automated tasks. We suggest that this is a direct demonstration of cerebral plasticity resulting in the resolution of acquired motor deficits.
缺血性脑损伤恢复的功能性神经解剖学基础尚不清楚。我们使用正电子发射断层扫描（PET）来研究纹状囊运动性中风恢复患者大脑功能组织的变化。在正常受试者和运动功能恢复的患者进行手指重复顺序对指运动期间，发现局部脑血流量（rCBF）有显著变化。当患者用未受影响的手执行运动任务时（激活定位于对侧感觉运动和运动前皮层以及同侧小脑）和用恢复的、先前瘫痪的手执行任务时（激活是双侧的且涉及新的皮层区域，尤其是40区），大脑激活模式存在差异。对患者组和正常受试者静息时的rCBF图进行比较，发现患者存在rCBF显著降低的区域（基底神经节、丘脑、岛叶皮层、脑干中与瘫痪手对侧的区域以及同侧小脑），这反映了缺血性病变所致功能障碍的分布。在患者恢复的手指运动期间，在同侧运动前皮层、双侧额眶/岛叶区域和40区、同侧基底神经节（缺血性病变位于对侧）以及对侧小脑发现了比正常受试者显著增加的激活。我们推测，这些发现可能是由与正常受试者执行通常相当简单的自动化任务所使用的通路不同的通路产生运动来解释的。我们认为，这是大脑可塑性导致获得性运动缺陷得以解决的直接证明。
