The role of the cerebellum in speech

项目摘要 这项建议调查小脑在言语中的作用，建立在理论模型的基础上， 实验方法已被证明有助于理解小脑在伸手和行走方面的功能。 神经影像学和病变研究提供了令人信服的证据，小脑是一个组成部分， 言语产生网络，尽管它在言语控制中的确切作用仍不清楚。此外，委员会认为， 小脑的损伤（退化性或局灶性）可导致共济失调性构音障碍，一种运动性语言障碍 其部分特征在于受损的发音和严重的时间缺陷。这笔赠款旨在弥补这一差距 小脑功能的理论模型与共济失调性构音障碍相关的言语症状之间的联系。 言语运动控制有两种机制：反馈和前馈控制。在反馈控制中， 扬声器使用感觉反馈（例如，他们自己的声音）来控制他们的讲话。在前馈控制中， 说话者使用从他们过去的演讲作品中获得的知识，而不是在线反馈， 他们的演讲。这个建议需要一个系统的计划来阐明小脑在前馈和 语音反馈控制一个中心假设是小脑在前馈中尤其重要 言语控制，但很少参与反馈控制。为了验证这个假设，我们将得到 从三种创新方法中收集证据：1）言语运动的神经心理学研究 小脑萎缩（CA）患者和匹配的健康人对实时改变的听觉反馈的反应 对照组，2）在接受θ脉冲串经颅磁刺激的健康对照组中进行的平行研究， 创建小脑的“虚拟病变”，以及3）CA患者的结构和功能研究，以检查 小脑病变部位、构音障碍症状与前馈和反馈控制之间的关系 能力 言语提供了一个重要的机会来检验目前关于小脑功能的理论 推广到一个新的效应器（声道）和感觉（听觉）域。它的目的是为了交流 施加了严格的频谱时间限制，这在其他运动域中是看不到的。此外，独特的 言语中反馈和前馈控制的平衡使我们能够检查这两种控制类型的变化 小脑损伤后关键的是，这是第一个研究理论上的联系的工作- CA患者的主动控制缺陷和与共济失调性构音障碍相关的言语症状，以及 他们的神经相关物

PROJECT SUMMARY This proposal investigates the role of the cerebellum in speech, building upon theoretical models and experimental methods that have proven useful in understanding cerebellar function in reaching and walking. Neuroimaging and lesion studies have provided compelling evidence that the cerebellum is an integral part of the speech production network, though its precise role in the control of speech remains unclear. Furthermore, damage to the cerebellum (either degenerative or focal) can lead to ataxic dysarthria, a motor speech disorder characterized, in part, by impaired articulation and severe temporal deficits. This grant seeks to bridge the gap between theoretical models of cerebellar function and the speech symptoms associated with ataxic dysarthria. Two mechanisms underlie speech motor control – feedback and feedforward control. In feedback control, speakers use sensory feedback (e.g., of their own voice) to control their speech. In feedforward control, speakers use knowledge gained from their past speech productions, rather than on-line feedback, to control their speech. This proposal entails a systematic plan to elucidate the role of the cerebellum in feedforward and feedback control of speech. A central hypothesis is that the cerebellum is especially critical in the feedforward control of speech, but has little involvement in feedback control. To explore this hypothesis, we will obtain converging evidence from three innovative methodologies: 1) Neuropsychological studies of speech-motor responses to real-time altered auditory feedback in patients with cerebellar atrophy (CA) and matched healthy controls, 2) Parallel studies in healthy controls undergoing theta-burst transcranial magnetic stimulation to create “virtual lesions” of the cerebellum, and 3) Structural and functional studies in CA patients to examine the relationship between cerebellar lesion location, dysarthria symptoms, and feedforward and feedback control ability. Speech provides an important opportunity to examine how well current theories of cerebellar function generalize to a novel effector (vocal tract) and sensory (auditory) domain. Its’ purpose for communication imposes exacting spectro-temporal constraints not seen in other motor domains. Furthermore, the distinctive balance of feedback and feedforward control in speech allows us to examine changes in both control types subsequent to cerebellar damage. Critically, this is the first work examining the link between theoretically- motivated control deficits in CA patients and the speech symptoms associated with ataxic dysarthria, as well as their neural correlates.