Doctoral Dissertation Research: Learning of Novel Phonetic Categories After Training in Perception and Production

人类拥有产生和理解语音的非凡能力。为了成功地学习一门语言，一个人必须了解一种特定语言中的声音类别是什么，以及是什么使各种声音彼此不同。例如，“r”和“L”在英语中属于不同的音类，但在其他一些语言中却不属于。学习如何区分这些声音并发出它们是学习一门语言的重要部分。目前，关于听者如何学习感知语音类别的知识很多；然而，关于说话人如何学习产出中的言语类别，以及在一种通道(即，感知或生成)中的学习如何与在另一种通道中的学习相关的信息，我们知道的要少得多。感知和生产之间的关系可以有多种形式。在一种模式下的学习总是会导致在另一种模式下的学习(即，一个人必须能够感知到一种区别，然后才能产生它)。两种模式的类别形成可以并行进行(即，感知和产生都可以同时学习新的声音)。或者，在一种方式下的学习实际上可能会阻碍另一种方式的学习(例如，在语音产生中的学习可能会扰乱语音感知的学习)。本研究旨在区分这些假说。这项研究中的实验旨在训练参与者新的声音类别，训练的重点是知觉或产生。然后对参与者进行知觉和生产两方面的测试。理清新的声音类别是如何在这两个通道中形成和获取的，不仅会让我们深入了解新的声音类别的学习过程，也会让我们深入了解这两个通道是如何联系的。本研究的发现将在理论和应用领域都具有重要意义。更好地理解类别是如何形成的，将有助于为第一语言学习者和第二语言学习者提供学习理论。理解言语知觉和产生是如何联系在一起的，将对发展知觉和产生的言语处理模型有所帮助。在应用领域，了解感知和产出的相互作用，特别是在声音类别的层面上，将对第二语言教师有利。此外，临床医生，如语音语言病理学家，将受益于更好地理解两种模式在学习(或重新学习)新的声音类别时是如何相互作用的。例如，如果患者在语音产生方面有障碍，他们可能能够使用他们完整的感知能力来重新训练受损的通道。

Humans possess a remarkable ability to produce and understand speech. In order to successfully learn a language, an individual must learn what the sound categories in a particular language are and what makes various sounds different from one another. For instance, "r" and "l" belong to different sound categories in English, but not in some other languages. Learning how to differentiate between these sounds and produce them is an important part of learning a language. Currently much is known about how listeners learn to perceive the speech sound categories; however, significantly less is known about how speakers learn about speech categories in production and how learning in one modality (i.e., perception or production) is related to learning in the other modality. The relationship between perception and production could take many forms. Learning in one modality could always lead learning in the other (i.e., an individual would have to be able to perceive a distinction before they could produce it). Category formation could occur in parallel for both modalities (i.e., both perception and production could learn about new sounds simultaneously). Alternately, learning in one modality could actually hinder learning in another modality (e.g., learning in speech production could disrupt learning in speech perception). This study aims to differentiate among these hypotheses. The experiments in this study are designed to train participants on novel sound categories with the training focusing on either perception or production. Then participants are tested in both perception and production. Untangling how new sound categories are formed and accessed in the two modalities will give insight not only into the learning process of new sound categories but also into how the two modalities are related. The findings of this study will be significant in both theoretical and applied domains. Having a better understanding of how categories are formed will help inform theories of learning for both first- and second-language learners. Understanding how speech perception and production are related will be informative in the development of models of speech processing in both perception and production. In the applied domain, understanding how perception and production interface, particularly at the level of sound categories, will be beneficial for second-language teachers. Furthermore, clinicians, such as speech-language pathologists, will benefit from a better understanding of how the two modalities interact when learning (or re-learning) novel sound categories. For instance, if patients have an impairment in speech production, they may be able to use their intact perceptual abilities to re-train the impaired modality.