Doctoral Dissertation Research Improvement Grant: Structure and Plasticity of Bilingual Sound Systems

在全球化和移民不断增加的时代，日常生活中听到的语言变得越来越不同质，随着不同语言背景的人之间的互动增加，各种口音和方言渗透到日常活动中。说不同语言的人使用不同的声学信息来确定他们听到的声音。例如，虽然英语和西班牙语都有“p”和“b”的发音对比，但听众会注意声音信号的不同方面（或不同的“声学线索”）来确定两种语言中这些声音的差异。这意味着一个人在听另一种语言或外国口音的演讲时，可能不会注意到与说话者相关的声音的相同部分，这可能会导致理解困难。为了有效地理解语音，听者必须迅速适应不同的口音，将注意力转移到与说话者相关的声音方面。提出的论文研究探讨了一个人的母语如何塑造声音类别的产生和感知方式，以及听众在面对这些类别的变化时适应的程度。研究的第一部分将探索哪些声音线索与区分“p”vs等对比最相关。英语和西班牙语中的“b”。第二组实验将探索如何改变这些声音类别的“边界”。也许最显著的适应例子是双语者，他们毫不费力地从一种语言的声音转换到另一种语言的声音。然而，单语听众也会改变他们的声音类别界限，以适应新的口音。这项拟议中的研究将探索声音类别的可塑性，或听者在面对与平常发音不同的语音时（如听到不熟悉的外国口音时）改变其类别界限的速度和幅度。该研究还将调查双语者是否比单语者表现出更强的可塑性。总之，拟议实验的结果将增加对不同语言中声音类别如何构成以及哪些因素导致这些类别的可塑性的理解，其更广泛的目标是为理解外国或外国口音语音所涉及的挑战提供见解。

In an era of increasing globalization and immigration, the speech heard on a daily basis is becoming less homogenous, and various accents and dialects permeate everyday activities as interactions between people from different language backgrounds increase. Speakers of different languages use different acoustic information to decide what sounds they are hearing. For example, while both English and Spanish have a sound contrast between "p" and "b," listeners pay attention to different aspects of the sound signal (or different "acoustic cues") to determine the difference between these sounds in the two languages. This means that a person listening to another language, or to foreign-accented speech, may not be paying attention to the same parts of the sound that are relevant for the speaker, which could lead to difficulties in intelligibility. For effective speech comprehension, listeners must rapidly accommodate to different accents by shifting their attention to the aspects of the sounds that are relevant for the speaker. The proposed dissertation research explores how one's native language can shape the way sound categories are produced and perceived, as well as to what extent listeners adapt when confronted with changes in these categories.The first part of the research will explore which acoustic cues are most relevant to distinguishing contrasts like "p" vs. "b" in English and Spanish. The second set of experiments will explore how the "boundaries" of these sound categories can be shifted. Perhaps the most striking example of accommodation is provided by bilinguals, who switch from using the sounds of one language to another effortlessly and instantaneously. However, monolingual listeners also shift their sound category boundaries to accommodate to new accents. The proposed research will explore the plasticity of sound categories, or the rate and magnitude at which listeners shift their category boundaries when confronted with speech that is pronounced differently than usual, as happens when hearing an unfamiliar foreign accent. The research will also investigate whether bilinguals show more plasticity than monolinguals. Together, the results of the proposed experiments will increase understanding of how sound categories are structured in different languages and which factors contribute to the plasticity of these categories, with the broader aim of providing insight into the challenges involved in understanding foreign or foreign-accented speech.