Doctoral Dissertation Research: Effects of phonological contrast on phonetic variation

每次有人说话，都会产生复杂的声波。了解这些声波的声学细节可以帮助改进语音识别技术，并提供对语言差异的洞察，这可能有助于语言学习。语言学和相关学科的大量研究表明，说话者的发音方式并不总是一样的。例如，英语中的“p”发音在不同的上下文中会有不同的发音(词首和词尾)，并且在不同的时间发音不同，仅仅因为说话者是人类。人们通常听不到这些差异，但它们存在于声学中，可以测量。语音的变异是很自然的，在每种语言中都会发生。然而，关于不同语言之间到底有多大差异，我们知之甚少。这项研究试图通过调查某些语言的说话者是否比其他语言的说话人有更多的发音变化以及如何解释这种差异来解决这一差距。一个经常假设的假设是，发音更多的语言的说话人在发音时会表现出更少的变化(更准确地说)。研究人员将从不同的语言收集数据，以检验和修正这一假设。他们还将开发具体的方法来测量语言中的声学可变性，然后将其应用于未来的工作。这些实验比较了印地语(“b”、“bh”、“p”和“ph”)和英语(“b”和“p”)中的“Stop”音，以及波兰语(“S”、“&amp；”和“sz”)和法语(“S”和“sh”)中发出的嘶嘶声。这两个实验都考察了两种语言对比的多个声学线索。该项目的第二部分将利用这些实验的结论来调查说话者是否模仿了他们听到的其他说话者的可变性。众所周知，说话人会根据他们最近听到的话来改变他们的发音，但还不知道说话人是否会根据他们听到的话来改变他们讲话中的变化量。为了解决这个问题，研究人员将进行一项模拟研究，让说话者在被提示说话之前先听一听，看看他们说话的可变性在听后是否发生了变化。这些研究的结果将增加对不同语言和环境中发音差异的理解。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Every time someone speaks, they produce complex sound waves. Understanding the acoustic details of these sound waves can help improve voice recognition technologies and provide insight on language differences which can potentially aid in language learning. A large body of work in linguistics and related disciplines has shown that speakers do not always pronounce sounds in the same way. For example, the sound "p" in English will be pronounced differently in different contexts (beginning of a word vs. end of word) and at different times simply because talkers are humans. People do not usually hear these differences, but they are present in the acoustics and can be measured. Variation in speech is natural and happens in every language. However, less is known about exactly how much variation occurs in different languages. This research seeks to address this gap by investigating whether speakers of some languages have more variable pronunciation than speakers of other languages and what might explain the difference.One frequently assumed hypothesis says that speakers of languages with more sounds will show less variation (be more precise) when they pronounce those sounds. The researchers will gather data from different languages to test and revise this hypothesis. They will also develop concrete methods for measuring acoustic variability in language which can then be applied to future work. The experiments compare stop sounds in Hindi ("b", "bh", "p" and "ph") and English ("b" and "p"), and sibilant sounds in Polish ("s", "ś", and "sz") and French ("s" and "sh"). Both experiments examine multiple acoustic cues to the contrasts in each language. The second portion of the project will use the conclusions from these experiments to investigate whether speakers imitate the variability of other speakers that they hear. It is well documented that speakers change their pronunciation based on speech they have recently heard, but it is not known whether speakers will change the amount of variability in their speech based on what they have heard. To address this question, the researchers will carry out an imitation study where speakers listen to speech before being prompted to speak to see if the variability in their speech changes after listening. The results of these studies will increase understanding of variability in pronunciation across different languages and contexts.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.