帕金森氏病言语运动障碍的神经机制研究

大约90%帕金森氏病患者都患有不同程度的言语障碍，但是目前仍缺乏对之有效的治疗手段，这主要是由于帕金森氏病的言语运动调控神经机制尚未得到阐释。言语运动的调控，依赖于前馈、听觉反馈和本体感觉反馈等感觉系统与发声运动系统的共同协调。研究表明，帕金森氏病患者由于基底节病变导致前馈功能和本体感觉反馈功能出现障碍，对听觉反馈依赖增大，但患者也无法正确感知来自听觉反馈的声音。据此，我们提出帕金森氏病患者由于过度依赖听觉反馈，令其听觉感知系统对反馈信息过度敏感，导致中枢神经系统难以对发声运动进行准确调控。本项目拟利用基于听觉反馈扰动的生物声学和脑电/事件相关电位技术，研究帕金森氏病患者利用听觉反馈对发声运动进行调控的神经生理学机制，揭示听觉反馈在帕金森氏病患者区分自我发声和外界声音过程中的作用机制，为以听觉反馈为核心治疗帕金森氏病患者言语障碍的康复新技术研究奠定理论基础。

Although 89% of individuals with Parkinson's disease (PD) are associated with motor speech disorders, the effective treatment techniques are quite limited. This is primarily attributable to the fact that neural mechanisms underlying the sensorimotor control of vocal production in individuals with PD are poorly understood. Successful execution of speech motor behavior relies on the coordination of sensory system (feedforward, auditory and somatosensory feedback) and motor system. It has been demonstrated that, however, individuals with PD fail to perceive the self-produced sound from auditory feedback. Moreover, they are also associated with the dysfunction of feedforward function and somatosensory feedback due to the impairment of the basal ganglia. Thus, we propose that there is an overreliance of auditory feedback in individuals with PD such that their audio-vocal system is highly sensitive to the changes in auditory feedback, which in turn leads to the abnormal sensorimotor control of vocal production. Using the acoustic and neurophysiological techniques that involve in the altered auditory feedback protocol, this project plans to investigate the neurophysiological mechanisms underlying auditory feedback control of vocal production in individuals with PD and they use auditory feedback to distinguish self-produced vocalizations from the external sounds at the cortical level. Our work will be of great help for the development of auditory-feeback-based new techniques to treat the motor speech disorders caused by PD.