基于执行功能调控的帕金森病运动性言语障碍神经机制研究

Speech motor disorder is one of the most common clinical symptoms in patients with Parkinson’s disease (PD), which has a serious impact on their quality of life. However, it is still lack of effective therapy for this problem until now, the major reason of which is that the speech motor control mechanisms are not comprehensively understood. The behavioral researches have found abnormal perception of auditory feedback during speech in patients with PD, which may lead to speech motor controlling disorder. By contrast, the speech motor can be significantly improved by changing the executive strategy, yet the intrinsic mechanisms are still not clear. Our pretest study has also shown that there are.significant differences between the vocal psychological and neurophysiological responses to auditory feedback perturbation during speech directed by different executive strategies in patients with PD. Therefore, we raise the hypothesis that the patients with PD have over reliance on auditory feedback during vocalization directed by internal cueing strategy, leading to unstable speech, on the opposite, during vocalization directed by external cueing strategy, the compensation of goal-directed movement leads to improvement of speech stability. In the present study, we will apply vocal psychological technology and electroencephalograthy/event-related potential technology basing on auditory.feedback perturbation, and source localization technology, to explore the executive modulatory mechanisms of speech motor disorders in PD. We hope to find theoretical evidence that supports the invention of innovative and effective therapy for the disorders.

运动性言语障碍是帕金森病最常见的临床症状之一，严重影响着患者的生活质量，但目前仍缺乏有效的治疗手段，原因在于其言语运动调控机制尚未得到全面阐释。行为学研究表明，帕金森病患者在言语运动过程中存在听觉反馈感知异常，导致言语运动调控障碍，然而，这种调控障碍却能通过改变执行功能调控策略而得到显著改善，但其内在神经机制尚不明确。我们的预实验同样发现，患者在内在提示和外在提示策略下进行言语运动所产生的心理声学响应及神经生理学响应均存在明显差异。据此，我们提出假设：帕金森病患者在内在提示策略下言语运动调控过度依赖于听觉反馈，导致发声不稳定；而在外在提示策略下，目标导向运动的代偿则使得言语运动稳定性提高。本项目拟采用基于听觉反馈扰动的心理声学、脑电/事件相关电位以及脑电溯源定位技术，研究帕金森病言语障碍的执行功能调控机制，为帕金森病言语障碍康复新技术的研发提供理论依据。

运动性言语障碍是帕金森病（PD）最常见的临床症状之一，PD患者在言语运动过程中存在言语运动调控障碍，然而，这种调控障碍却能通过改变执行功能调控策略而得到显著改善，但其内在神经机制尚不明确。本项目围绕PD基于运动执行控制的言语运动调控机制进行研究，采用基于听觉反馈基频扰动（FAF）的心理声学和事件相关电位（ERP）技术，通过比较PD患者和正常对照组在内在提示和外在提示策略下面对发声过程中的FAF所产生的行为学响应和皮层活动模式，研究PD患者在不同运动执行控制模式下的言语运动调控神经机制。结果显示：PD组在外在提示发声任务中所产生的N1响应波幅显著小于内在提示发声任务，而在正常对照组中则不存在这种差异；在内在提示发声任务中，PD组所产生的N1响应波幅显著大于正常对照组；在外在提示发声任务中，两组受试者的皮层反应不存在统计学差异。上述研究结果表明，PD患者在不同运动执行控制策略下言语运动调控神经机制存在差异，这可能是由运动规划和自动化的功能障碍以及目标导向运动的功能代偿所致。这不仅从实时调控的角度阐释了运动执行控制策略在PD运动性言语运动障碍神经机制中的重要作用，并且为基于运动执行控制策略的言语康复治疗方法提供了理论基础。