Neural control and sensorimotor mechanisms in stuttering

描述(由申请人提供)：了解口吃的基本神经机制被广泛认为是知情诊断和治疗的基础。这一重要知识所需的基石是口吃的理论框架，该框架解释了各种主要的和相关的语音特征，并与经验证的感觉运动控制和神经功能模型一致。这里提出的研究计划采用了一种全面的神经生物学方法，通过一系列综合的理论驱动、假设驱动的实验来解释口吃的神经基础。平行的心理物理(运动学、感觉运动适应、机械/感觉干扰)和神经成像(FMRI)实验将被用来解决根据我们的理论框架可能与口吃有关的言语感觉运动控制的特定方面。这一系列实验研究的具体目的是在有口吃和不口吃的个体身上调查(A)获得和巩固中枢运动指令到声道肌肉系统之间的映射的神经表示(即内部模型)的能力，以及这些动作的感觉后果，(B)将听觉和运动传入信号整合到言语感觉运动控制的前馈和反馈成分中的效率，以及(C)言语产生的神经底物的激活时间进程和功能连接。这是一个由科学家合作研究的项目，他们拥有重叠和互补的专业领域，并在两个表演地点使用最先进的仪器指导研究小组。结合这些网站的专业知识和资源，将能够在行为、生理和神经操作水平上对口吃和非口吃儿童和成人的感觉运动系统进行创新研究。这些深入的研究有可能为口吃者的言语运动控制系统的发展和状态提供信息，并为研究和临床治疗提供新的方向。因此，这项工作与公共卫生的直接相关性在于它有助于理解口吃背后的神经机制，并通过产生这种新的见解，促进改进诊断和治疗方法的发展。

DESCRIPTION (provided by applicant): Understanding the basic neural mechanisms underlying stuttering is widely acknowledged as fundamental to informed diagnosis and treatment. The required cornerstone for this important knowledge is a theoretical framework of stuttering that accounts for various primary and associated speech characteristics and that is consistent with empirically-verified models of sensorimotor control and neural functioning. The research program proposed here takes a comprehensive neurobiological approach to explaining the neural basis of stuttering through an integrated series of theoretically-motivated, hypothesis-driven experiments. Parallel psychophysical (kinematics, sensorimotor adaptation, mechanical/sensory perturbations) and neuroimaging (fMRI) experiments will be conducted to address selected aspects of speech sensorimotor control that, according to our theoretical framework, may be implicated in stuttering. Specific aims of the series of experimental studies are to investigate in individuals who do vs. who do not stutter (a) the ability to acquire and consolidate neural representations (i.e., internal models) of the mappings between central motor commands to the vocal tract musculature and the sensory consequences of those actions, (b) the efficiency of integrating auditory and kinesthetic afferent signals into both the feedforward and feedback components of speech sensorimotor control, and (c) the activation time course and functional connectivity of the neural substrates underlying speech production. This is a collaborative program of research by scientists who have overlapping as well as complementary areas of expertise and who direct research groups using state-of-the-art instrumentation at two performance sites. Combining the expertise and resources from these sites will allow innovative investigations of the sensorimotor systems of stuttering and nonstuttering children and adults at behavioral, physiological, and neural levels of operation. These in-depth studies have the potential to inform on the development and state of the speech motor control system in individuals who stutter, and to suggest new directions for research and clinical management. Thus, this work's direct relevance to public health lies in its contributions to understanding the neural mechanisms underlying stuttering and-by generating such new insights-facilitating the development of improved approaches to diagnosis and treatment.