Training-induced modifications of corticospinal reactivity in severely affected stroke survivors
Training-induced modifications of corticospinal reactivity in severely affected stroke survivors
复制标题
DOI：
10.1007/s00221-012-3163-z
复制
发表时间：
2012-08-01
影响因子：
2
通讯作者：
Carson, Richard G.
中科院分区：
文献类型：
--
作者：
Barker, Ruth N.;Brauer, Sandra G.;Carson, Richard G.
当允许获得适当形式的康复，许多严重影响中风幸存者表现出上肢功能恢复的能力远远超过以前认为可能的。然而，在这些严重受损的个体中，手臂功能改善的机制仍然知之甚少。在一组患有慢性上肢轻瘫的严重卒中幸存者中进行了一项探索性研究，以调查大脑可塑性和功能适应能力，以响应使用SMART Arm器械进行的12小时伸展训练。入组了28例卒中幸存者。11名健康成人提供了规范性数据。为了评估同侧和对侧皮质脊髓通路的完整性，经颅磁刺激被应用于在肘部伸展任务中诱发肱三头肌的反应。当存在时，对侧运动诱发电位（MEP）与健康成年人相比延迟和振幅降低。训练后，对侧反应更普遍，其平均发病潜伏期减少。同侧MEP无可靠变化。在训练前表现出对侧MEP的卒中幸存者比那些最初没有表现出对侧反应的人实现了更高水平的手臂功能，并表现出更大的性能改善。此外，对侧MEP的起始潜伏期的减少与手臂功能的改善呈正相关。我们的研究结果表明，当严重受损的中风幸存者提供了适当的康复方式，皮质脊髓反应性的修改发生与上肢功能的持续改善。
When permitted access to the appropriate forms of rehabilitation, many severely affected stroke survivors demonstrate a capacity for upper limb functional recovery well in excess of that formerly considered possible. Yet, the mechanisms through which improvements in arm function occur in such profoundly impaired individuals remain poorly understood. An exploratory study was undertaken to investigate the capacity for brain plasticity and functional adaptation, in response to 12-h training of reaching using the SMART Arm device, in a group of severely affected stroke survivors with chronic upper limb paresis. Twenty-eight stroke survivors were enroled. Eleven healthy adults provided normative data. To assess the integrity of ipsilateral and contralateral corticospinal pathways, transcranial magnetic stimulation was applied to evoke responses in triceps brachii during an elbow extension task. When present, contralateral motor-evoked potentials (MEPs) were delayed and reduced in amplitude compared to those obtained in healthy adults. Following training, contralateral responses were more prevalent and their average onset latency was reduced. There were no reliable changes in ipsilateral MEPs. Stroke survivors who exhibited contralateral MEPs prior to training achieved higher levels of arm function and exhibited greater improvements in performance than those who did not initially exhibit contralateral responses. Furthermore, decreases in the onset latency of contralateral MEPs were positively related to improvements in arm function. Our findings demonstrate that when severely impaired stroke survivors are provided with an appropriate rehabilitation modality, modifications of corticospinal reactivity occur in association with sustained improvements in upper limb function.