CONSTRAINTS AND STRATEGIES IN SPEECH PRODUCTION

本研究的长期目标是有助于理解言语产生的运动控制，包括其变异性，效率和交际效果。我们将建立在我们的声学目标，清晰度与经济的努力，动力学性能限制和声道建模，并在新的合作者的工作初步调查结果。我们将根据以下假设通过实验来完善理论概述：（1）音位对比产生的音段控制机制是基于声学目标的。我们将研究达到这些目标的运动等效性。(2)声学目标部分地由运动命令和发音运动之间以及发音和声音之间的饱和效应（非线性量子关系）确定。我们将在咬块实验中研究饱和效应。(3)为了实现这些目标，计划语音运动，以便以最小的努力实现感知对比。我们将研究在不同的语音条件下的语音清晰度和发音努力的措施。(4)为了实现声学目标，编程必须利用运动命令和声学结果之间关系的内部模型。我们将用一个言语感觉运动适应范例来检验这种内部模型的性质。(5)运动指令和声学结果之间的关系包括生物力学约束，我们研究与生理声道模型。这项工作将包括：（a）进一步开发和使用声门上声道的特定于说话者的生理/生物力学模型，（B）从几个说话者收集详细的声学、运动、力、EMG、MRI和空气动力学数据，以提供用于模型开发和验证以及用于生物力学饱和效应的定量探索的基础，以及（c）控制模型的进一步开发及其在关于声学目标、饱和效应、努力的经济性和动力学约束的假设的测试中驱动生物力学模型的用途。(6)感知和产生之间的关系的性质及其内部模型的完善程度可能因说话者而异。我们测量说话者的敏锐度，在语音识别和这些措施之间的差异，在语音运动学和声学。在这些研究中，我们将使用我们的EMMA运动传感器系统记录和分析下颌骨，嘴唇和舌头上的声学信号和点的运动;我们还使用MRI收集解剖数据，并测量EMG，接触压力，气压和气流。我们还进行了几种感知实验，并将结果与生产实验的结果进行了比较。

The long-range goal of this research is to contribute to an understanding of the motor control of speech production, including its variability, efficiency and communicative effectiveness. We will build on our initial findings of acoustic goals, clarity versus economy of effort, kinetic performance limits and vocal-tract modeling, and on the work of new collaborators. We will refine a theoretical overview with experiments based on the following hypotheses: (1) Segmental control mechanisms for the production of phonemic contrasts are based on acoustical goals. We will examine motor equivalence in reaching those goals. (2) The acoustic goals are determined partly by saturation effects (non-linear quantal relations) between motor commands and articulatory movements and between articulation and sound. We will study saturation effects in a bite block experiment. (3) To achieve the goals, speech movements are planned so that perceptual contrast is achieved with minimal effort. We will examine measures of speech clarity and articulatory effort under varying speech conditions. (4) Programming to achieve acoustic goals must utilize an internal model of the relation between motor commands and acoustic results. We will examine properties of that internal model with a speech sensorimotor adaptation paradigm. (5) The relation between motor commands and acoustic results includes biomechanical constrains, which we study with physiological vocal-tract models. This work will include: (a) further development and use of speaker-specific physiological/biomechanical models of the supra-glottal vocal tract, (b) collection of detailed acoustic, movement, force, EMG, MRI and aerodynamic data from several speakers to provide bases for model development and validation and for quantitative exploration of biomechanical saturation effects, and (c) further development of control models and their use in driving the biomechanical models in tests of hypotheses about acoustic goals, saturation effects, economy of effort and dynamical constraints. (6) The nature of relations between perception and production and their degree of refinement of the internal model may differ across speakers. We measure speakers' acuity in speech discrimination and relate those measures to differences among them in speech kinematics and acoustics. In these studies we will record and analyze the acoustic signals and movements of points on the mandible, lips and tongue using our EMMA movement transducer system; we also gather anatomical data with MRI and we make measurements of EMG, contact pressures, air pressure and air flow. We also conduct several kinds of perceptual experiments and compare the results with those from the production experiments.