Direct and Indirect Measures of Glottal Volume Velocity

描述(申请人提供)：言语研究的一个最终目标是建立一个共同的理论框架，将生理学、声学和言语知觉联系起来。这种统一的方法对于解释组织运动最终如何导致对语音的感知是必不可少的。这项研究评估了语音产生的线性源-过滤器理论背后的一个主要假设：声门源和声道是独立的，因此可以使用线性技术有效地分离。由于同样的假设是传统的逆滤波(基于线性源-滤波理论)的基础，因此结果也将用于验证该技术用于估计声门体积速度。逆滤波对声源的估计将与以更直接但更具侵入性的方式计算的音量速度进行比较。由于从伦理上讲，无法在活人身上直接测量体积速度，因此将在切除的人类喉部和活体犬模型中产生直接估计，方法是使用风速测量技术测量声门处喷出的粒子速度，然后将结果乘以由高速成像得出的声门面积测量。研究将检查一系列正常和病态的发音构型，与反滤波数据的比较将导致必要时改进技术以提高过滤器的有效性。通过比较由喉部建模得到的体积速度估计值和通过对声学信号进行逆滤波而间接得到的体积速度估计值，将建立逆滤波估计体积速度的有效性。这些研究还将阐明声门动力学和发声声学之间的关系，从而最终有助于加强对发声的生物力学和线性源滤波理论的实用限制的基本理解。这项研究的主要假设是，线性源过滤理论的假设适用于特定的、有限的发声区域。这项研究的目标是确定这些假设不成立的区域，并量化各种发声构型中来源和过滤之间的相互作用。

DESCRIPTION (provided by applicant): An ultimate goal of speech research is to develop a common theoretical framework that will link together physiology, acoustics, and speech perception. Such a unified approach is essential in explaining how tissue movement finally results in the perception of speech sounds. The proposed research evaluates a major assumption underlying the linear source-filter theory of speech production: that the glottal source and vocal tract are independent, and thus can be effectively separated using linear techniques. Because this same assumption underlies conventional inverse filtering (which is based on linear source-filter theory), results will also serve to validate this technique for estimating the glottal volume velocity. Estimates of the voice source from inverse filtering will be compared to the volume velocity calculated in a more direct but invasive manner. Because the volume velocity cannot ethically be measured directly in living humans, direct estimates will be generated in excised human laryngeal and in vivo canine models, by using anemometry to measure the exit jet particle velocity at the glottis and then multiplying this result by glottal area measures derived from high-speed imaging. Studies will examine a great range of normal and pathological phonatory configurations, and comparisons to inverse filtered data will lead to modifications in techniques to improve filter validity when necessary. By comparing volume velocity estimates from laryngeal modeling to those indirectly derived from inverse filtering the acoustic signal, the validity of inverse filtering for estimating the volume velocity will be established. Such studies will also illuminate the relationship between glottal dynamics and vocal acoustics, and thus will ultimately contribute to an enhanced basic understanding of the biomechanics of voice production and the practical limits of linear source filter theory in general. The primary hypothesis of this research is that the assumptions of linear source-filter theory hold for specific, limited regions of phonation. The goal of this research is to determine the regions over which these assumptions do not hold, and to quantify the interactions between source and filter across a wide variety of vocal configurations.