Temporal Coordination in the Motor Speech System

描述（由申请人提供）：本研究申请旨在研究正常衰老和损伤导致的神经运动限制如何在言语过程中导致功能单位的不同动态组织。研究考察了多个发音器官（嘴唇，下巴和声音）是如何协调的，以实现在正常和机械干扰的说话条件下感知准确的语音。将考虑患有言语失用症（AOS）的言语运动编程障碍的个体。AOS破坏了咬合架间的协调。研究表明，特定的肌肉群或发音器官是动态组织的，作为功能单位，根据神经运动和语音系统的机械约束。因此，据预测，这些单位的组织将根据说话者的神经运动能力和说话任务的要求而变化。在正常老化过程中产生的神经运动约束和AOS的神经运动约束不同的假设下，可以预测，不同的运动组织模式将被发现在扬声器与AOS与年轻和年长的典型扬声器在响应机械扰动。这些组织的差异将通过检查语音偏移和发病的时间和运动学特性（相对位移和嘴唇闭合的持续时间，嘴唇闭合和打开的峰值速度和加速度）的嘴唇和下巴在生产/papa/在典型的和扰动的条件下进行测试。在健康的说话者中，将测试两种说话速率，以确定说话速率是否可以解释正常老化或损伤的任何影响。扰动将包括在早期（唇闭合开始前约70 msec）或晚期（闭合开始后约20 msec）在下唇上向下施加的非预期50 g载荷。有人认为，对早期扰动的反应反映了运动编程过程，而对晚期扰动的反应反映了运动执行过程。AOS是一个理想的系统，因为它只破坏前者。DIVA神经网络模型用于开发特定的预测，并将在此模型和其他当前运动控制模型的背景下解释结果。

DESCRIPTION (provided by applicant): This research application aims to investigate how neuromotor constraints arising from normal aging and from impairment result in different dynamic organization of functional units during speech. Studies examine how multiple articulators (lips, jaw, and voice) are coordinated to achieve perceptually accurate speech under normal and mechanically perturbed speaking conditions. Individuals with the speech motor programming disorder of Apraxia of Speech (AOS) will be considered. AOS disrupts inter-articulator coordination. Research has suggested that specific muscle groups or articulators are dynamically organized, as functional units, according to neuromotor and mechanical constraints of the speech system. As a result, it is predicted that the organization of these units will vary as a function of the neuromotor abilities of the speaker and the demands of the speaking task. Under the assumption that the neuromotor constraints arising from the normal aging process and those of AOS are different, it is predicted that different patterns of motor organization will be found in speakers with AOS versus young and older typical speakers in response to mechanical perturbation. These differences in organization will be tested by examining timing of voice offset and onset and kinematic properties (relative displacement and duration for lip closure, peak velocity and acceleration of lip closing and opening) of the lips and jaw in the production of/papa/under typical and perturbed conditions. In healthy speakers, two speaking rates will be tested to determine whether speech rate can explain any effects of normal aging or impairment. Perturbation will consist of an unexpected 50 g load applied downward on the lower lip either early (approximately 70 msec prior to onset of lip closure) or late (approximately 20 msec after onset of closure). It has been suggested that response to early perturbations reflects motor programming processes while response to late perturbations reflects movement execution processes. AOS is an ideal system as it only disrupts the former. The DIVA neural network model is used to develop specific predictions and results will be interpreted in the context of this and other current models of motor control.