Towards Standardizing Perceptual Voice Quality Measures

对声音质量的判断极大地影响了患者对自己声音的看法，也影响了临床医生的决策 开始并继续治疗。质量判断也被用来作为衡量工具的标准。 语音的测量是有效的。然而，语音质量的这些“主观”测量并不高。 由于可靠性和未经检验的有效性问题，它被认为是临床或研究工具。我们 假设语音质量测量中的问题不是源于收听者，而是源于 来衡量听众听到了什么。该研究不同于传统的 通过应用语音合成器分级量表法对病理性嗓音质量的基本问题进行研究 关于语音质量测量的可靠性和有效性，并确定感知的重要性， 声音质量感知的声学要素。在这种方法中，听众调整合成器 参数来实现与原始语音的感知匹配。这种调整技术的方法 明确地将声学信号与语音质量联系起来。我们假设这种语言链上的联系 通过为听众提供 一个客观的工具（合成器），用于量化他们所听到的。本研究主要集中在四个方面 具体目标。首先，我们将扩大，完善和自动化我们的合成器，以增加功率，灵活性， 易于使用。其次，我们将应用合成器来检查几个关键的感知重要性， 病理声音的方面，包括源频谱的形状，周期加倍，和 语音源中谐波和非谐波（噪声）能量的感知相互作用。在每种情况下，我们将 确定哪些声学特征在感知上是重要的，以及这些特征是否与 其他人，我们将估计参数的刚刚可察觉的差异作为数量的指数， 在这个维度上有临床意义的声学变化。第三，我们将评估临床医生的能力， 将合成器用作临床上测量语音质量的工具。我们还将重新审视 在评级协议中使用合成锚作为调整任务方法的替代方案。最后我们将 通过比较来自以下方面的感知测量来评估合成技术的外部有效性： 持续元音到那些来自连续语音的元音。通过增加功率和易用性， 合成器的使用，检查听者对重要声学变量的敏感度，并研究 这种方法的普遍性，提出的研究将带来我们的目标，一个标准化的语音质量 评估协议触手可及。

Judgments of voice quality contribute greatly to patients' opinions of their voice, and to a clinician's decision to initiate and continue treatment. Quality judgments are also used as a standard against which instrumental measures of voice are validated. Nevertheless, these "subjective" measures of voice quality are not highly regarded as either clinical or research tools, because of problems with reliability and untested validity. We hypothesize that problems in voice quality measurement do not originate within the listener, but rather derive from the methods used to measure what listeners hear. The proposed research departs from traditional rating scale methods by applying a speech synthesizer for pathological voice quality to study basic issues concerning reliability and validity of voice quality measures, and to determine the perceptual importance of the acoustic elements that underlie voice quality perception. In this approach, listeners adjust synthesizer parameters to achieve a perceptual match to the original voice. This method of adjustment technique explicitly links the acoustic signal to voice quality. We hypothesize that this linkage across the speech chain increases the validity, reliability, and utility of the resulting perceptual responses, by providing listeners with an objective tool (a synthesizer) for quantifying what they hear. The proposed research focuses on four specific aims. First, we will expand, refine, and automate our synthesizer, to increase power, flexibility, and ease of use. Secondly, we will apply the synthesizer to examine the perceptual importance of several key aspects of pathologic voices, including the shape of the source spectrum, period doubling, and the perceptual interactions of harmonic and inharmonic (noise) energy in the voice source. In each case, we will determine which acoustic features are perceptually important and whether these features interact with others, and we will estimate just-noticeable-differences for the parameter as an index of the amount of acoustic change that is clinically meaningful on that dimension. Thirdly, we will evaluate clinicians' ability to apply the synthesizer as a tool for measuring voice quality in the clinic. We will also revisit the use of synthetic anchors in rating protocols as an alternative to the method of adjustment task. Finally, we will evaluate the external validity of the synthesis technique by comparing perceptual measures derived from sustained vowels to those derived from continuous speech. By increasing the power and ease of the synthesizer's use, examining listener sensitivity to important acoustic variables, and studying the generalizability of this approach, the proposed research will bring our goal of a standardized voice quality evaluation protocol within reach.