脑卒中言语产生中感觉运动整合异常的多模态神经影像学研究

Stoke has become the leading cause of the disabilities in adults, and 60% of stroke patients with communication problems suffer from motor speech disorders. However, clinical rehabilitation of motor speech disorders caused by stroke has not advanced for a long time, and the underlying mechanisms remain largely unclear. Successful control of speech motor behavior is a result of the integration of auditory feedback information with the vocal motor systems. It is speculated, accordingly, that motor speech disorders caused by stroke may be related to the abnormal auditory-motor integration for speech production. With a combination of the altered-auditory-feedback-based psychoacoustics, event-related potential (ERP) methods, the lesion-behavior-mapping-based structural MRI analysis and diffusion tensor imaging (DTI) techniques, therefore, the present project aims to explore the neural mechanisms underlying auditory-vocal integration for speech production in patients after stroke. Our research will show the pattern of vocal compensation and the time-frequency characteristics of cortical ERPs in response to pitch feedback perturbations perceived by adults after stroke during speech production at the group level, and reveal the relationship between abnormalities in the brain structures and neurobehavioral performances in speech motor control at the individual level. Findings from the present project will reveal the neurobehavioral characteristics and the structural basis of speech motor control disorders after stroke and deepen our understanding of the brain structure-speech motor control from the perspective of brain lesion, thereby, providing evidence for the use of noninvasive neuromodulation techniques to treat the motor speech disorders caused by stroke.

脑卒中是成人致残的首要原因，交流障碍中运动性言语障碍发生率超过60%。但临床康复长期缺乏突破性进展，内在神经机制至今不明。言语运动调控是听觉反馈信息与发声运动系统有效整合的结果。脑卒中导致的运动性言语障碍可能与言语产生中听觉感知-发声整合异常有关。据此，本项目拟利用基于听觉反馈扰动的声学技术和事件相关电位分析技术，结合基于脑损伤病灶-行为表现映射的结构磁共振和弥散张量成像技术，研究脑卒中言语产生中听觉感知-发声运动整合的神经机制，从组间水平上阐明脑卒中患者利用听觉反馈调控言语运动的补偿性声学响应模式和皮层诱发电位时-频特性；从个体水平上揭示脑结构网络异常与言语运动调控神经-行为活动之间的相关性。本项目可以明确脑卒中言语运动调控障碍的神经-行为特征及其内在的脑结构基础，有助于从脑损伤的角度理解大脑结构-言语运动调控的内在关联，为使用非侵入性神经调控技术治疗脑卒中运动性言语障碍提供科学依据。

脑卒中是成人致残的首要原因，交流障碍中运动性言语障碍发生率超过60%。但临床康复长期缺乏突破性进展，内在神经机制至今不明。言语运动调控是听觉反馈信息与发声运动系统有效整合的结果。脑卒中导致的运动性言语障碍可能与言语产生中听觉感知-发声整合异常有关。本项目利用基于听觉反馈扰动的声学技术和事件相关电位分析技术，结合基于脑损伤病灶-行为表现映射（VLSM）的结构磁共振和弥散张量成像技术，以及神经调控技术（TMS和tDCS）和基因组学技术，以脑卒中患者、帕金森病患者、脊髓小脑共济失调患者等多种神经疾病患者为对象，研究言语产生中听觉感知-发声运动整合障碍的神经生物学机制和神经调控康复技术，取得了一系列高水平的研究成果：1）大脑皮层和皮层下组织的形态学特征以及基因多态性与言语运动调控的个体差异密切相关；2）年龄的老化、神经系统疾病的特异性以及发声训练形成的神经可塑性能够对言语运动行为产生差异化影响；3）大脑皮层和皮层下组织兴奋性的变化与言语运动调控行为存在因果性关联，并且因果关系并不相同；4）TMS和tDCS技术能够改变小脑的兴奋性，进而对言语运动障碍起到改善性作用。本项目执行期间，项目组在Cereb. Cortex、Hum. Brain Mapp.、Neurobiol. Aging等国际权威期刊发表高水平SCI收录论文15篇,在中国康复医学杂志、中华物理医学与康复杂志和中国康复理论与实践发表中文期刊论文3篇，培养研究生5名、博士后2名。本项目的各项研究内容顺利完成，实现了预期的研究目标。本项目的研究结果对理解脑卒中言语运动障碍发生的神经机制，以及利用神经调控技术进行个体化的精准干预具有重要意义。