Constraints and Strategies in Speech Production

描述（由申请人提供）：拟议的研究涉及有关计划和执行言语运动方式的假设。这些假设是由一个计算模型的神经控制的语音运动结合生物力学为基础的声道模型。为了验证这些假设，我们与说话者和听者进行实验，测量发音运动、语音声学、感知和大脑激活。我们操纵语言条件（例如，清晰语音与快速语音）、音素语境和语音声音类别，并且我们引入瞬时和持续扰动。我们还进行了模拟实验中，我们适应声道模型的形态，个别发言人。该声道模型的运动由我们的神经控制模型指挥，用于我们实验中使用的相同话语和条件，并且将所产生的运动和声学与建模扬声器的运动和声学进行比较，以测试该模型。该研究解决了3个相互关联的问题：1。发音运动的音素和音节目标的本质。在这里，我们研究的语音条件和扬声器的差异对听觉目标的元音的影响;扬声器的区别能力的影响，他们产生的音素对比;和听觉和发音扰动的影响，音素对比度和它们的相互作用与声音类和扬声器敏锐度。2.反馈和前馈机制在言语运动控制中的作用。这些控制子系统的性能进行了探讨，通过引入不可预测的和持续的扰动。我们测试基于模型的假设，这些干预引起的大脑激活和声学和发音轨迹的变化。3.音素与较大单位连结之运动轨迹规划。在这项研究中，我们调查的规划运动的串联的话。我们测量发音动作的手势重叠和他们的声学和感知相关，以测试假设，这种重叠留下可感知的听觉线索的听众。我们相信，这些研究将提供重要的信息，神经控制机制的基础上的语音生产。

DESCRIPTION (provided by applicant): The proposed research addresses hypotheses concerning the way speech movements are planned and executed. The hypotheses are guided by a computational model of the neural control of speech movements combined with a biomechanically based vocal-tract model. To test these hypotheses, we conduct experiments with speakers and listeners in which we measure articulatory movements, speech acoustics, perception, and brain activation. We manipulate speech condition (e.g., clear vs. fast speech), phonemic context, and speech sound class, and we introduce transient and sustained perturbations. We also perform simulation experiments in which we adapt the vocal-tract model to the morphologies of individual speakers. Movements of this vocal-tract model are commanded by our neural control model for the same utterances and conditions used in our experiments, and the resulting movements and acoustics are compared to those of the modeled speaker, in order to test the model. The research addresses 3 inter-related issues: 1. The nature of phonemic and syllabic goals for articulatory movements. Here we study the effects of speaking conditions and speaker differences on auditory goals for vowels; the effects of speakers' discriminative capacities on the phoneme contrasts they produce; and the effects of auditory and articulatory perturbations on phonemic contrast and their interaction with sound class and speaker acuity. 2. The role of feedback and feedforward mechanisms in the control of speech movements. The performance of these control sub-systems is probed by introducing unpredictable and sustained perturbations. We test model-based hypotheses about changes in brain activation and acoustic and articulatory trajectories elicited by each of these interventions. 3. Movement trajectory planning in the concatenation of phonemes and larger units. In this study we investigate the planning of movements in the concatenation of words. We measure articulatory movements in gestural overlap and their acoustic and perceptual correlates in order to test the hypothesis that such overlap leaves perceptible acoustic cues for listeners. We believe these studies will provide important information regarding the neural control mechanisms underlying speech production.