心理语言评价指导经颅直流电刺激靶向治疗失语症的疗效及其机制研究

Aphasia has increasingly become a “bottleneck” that inhibits comprehensive rehabilitation in the patients with brain injuries. With the development of cognitive neuroscience, characterization of aphasia has shifted from descriptions of the language tasks that are impaired by brain damage to identification of the disrupted cognitive processes underlying language. Moreover, most of modules in psycholingustic processing model have definite cortical localization. Transcranial direct current stimulation (tDCS) could benefit the patients with post-stroke aphasia. Currently, most studies about tDCS treatment on aphasia focused on Broca’s area, Wernicke’s area or homologous area in right hemisphere. However, such tDCS treatment without considering the disrupted psycholingustic processing modules could not achieve the optimal effect. Therefore, we hypothesized that targeted tDCS over specific cortical areas guided by psycholingustic assessment might promote highly individualized approach to treatment. EEG nonlinear dynamics analysis (NDA) can reflect cortical activation during language tasks. In this study, we would investigate the effect of targeted tDCS over specific cortical areas guided by psycholingustic assessment in the patients with post-stroke aphasia and cortical excitability measured with NDA. This study would also observe the interconnections among targeted stimulation areas and distant nodes of language cortical networks with NDA. The final goal is to clarify the recovery mechanism of effect of tDCS on language function in the patients with post-stroke aphasia.

失语症日益成为阻碍脑损伤患者全面康复的“瓶颈”。随着认知神经科学的进展，对失语症的认识已经从“模糊”分类转变到心理语言加工的功能模块化，且多数模块有了明确的脑功能定位。经颅直流电刺激（tDCS）对脑卒中后失语症显示出其特定的治疗效果，目前国际上应用tDCS治疗失语症刺激部位集中在Broca区、Wernicke区或其右侧对应区，这种不考虑语言加工模块损害的治疗可能达不到最佳疗效。据此我们提出tDCS靶向刺激受损的心理语言加工模块对应的脑区，能更有针对性地改善受损语言功能的假设。脑电非线性分析（NDA）可以评估失语症患者在语言任务下相关皮层的激活状态。本研究将观察失语症心理语言评价确定受损模块对应脑区作为tDCS靶向治疗脑卒中失语症患者的疗效；并且通过NDA观察失语症患者的皮层兴奋状态，以及靶刺激区与远隔网络节点相互联系的变化情况，初步阐明tDCS对脑卒中后失语症患者语言功能恢复作用的机制。

语症日益成为阻碍脑损伤患者全面康复的“瓶颈”。随着认知神经科学的进展，对失语症的认识已经从“模糊”分类转变到心理语言加工的功能模块化，且多数模块有了明确的脑功能定位。经颅直流电刺激（tDCS）对脑卒中后失语症显示出其特定的治疗效果，目前国际上应用tDCS治疗失语症刺激部位集中在Broca区、Wernicke区或其右侧对应区，这种不考虑语言加工模块损害的治疗可能达不到最佳疗效。据此我们提出tDCS靶向刺激受损的心理语言加工模块对应的脑区，能更有针对性地改善受损语言功能的假设。脑电非线性分析（NDA）可以评估失语症患者在语言任务下相关皮层的激活状态。本研究将观察失语症心理语言评价确定受损模块对应脑区作为tDCS靶向治疗脑卒中失语症患者的疗效；并且通过NDA观察失语症患者的皮层兴奋状态，以及靶刺激区与远隔网络节点相互联系的变化情况，初步阐明tDCS对脑卒中后失语症患者语言功能恢复作用的机制。.我们应用NDA，对近150例失语症患者通过tDCS刺激感兴趣区皮层神经细胞，对失语症患者皮层兴奋性改变与语言功能改善的关系进行了研究。我们发现：左侧大脑唇舌发音皮层投射区（M1、S1）较Broca区阳极tDCS，可以更好地改善脑卒中恢复期重度言语失用症的言语障碍；根据汉语失语症心理语言评价结果指导tDCS靶向治疗感觉性失语症，可以促进恢复期感觉性失语症患者听理解能力的提高，左颞上回中部在感觉性失语症患者的听觉语音分析和词汇理解起到重要作用；Wernicke区tDCS能更显著地改善脑卒中后额颞损伤失语症患者的图命名能力，其原因可能是后部语言区刺激涉及了Wernicke区及其邻近的语言相关脑区有关。针对疾病（功能障碍）的神经损伤机制进行tDCS靶向治疗、精准治疗是一个趋势，这要求我们从神经网络的角度入手，探索病变相关脑区在神经损伤机制中的主次关系，从而进行精准的tDCS靶向治疗。因此，根据汉语失语症心理语言评价结果指导tDCS进行靶向治疗，可能成为脑卒中患者失语症新的有效手段。