Doctoral Dissertation Research: Investigation of second language lexical representation and processing of Mandarin tones

作为中华人民共和国的国语，汉语普通话在现代世界具有明显的重要性。因此，我们对如何更有效地学习普通话的理解的进步符合美国的国家利益。普通话是一种词汇语调语言，通过音节上的音高线索来区分单词。众所周知，以英语为母语的人学习词汇语调是困难的，然而，在学习的最初阶段之外，人们并没有很好地理解困难的性质及其原因。本项目将解决两个主要问题：第一，成人第二语言学习者对普通话声调类别的心理表征是怎样的？第二，学习者在实时单词识别过程中遇到的困难的性质是什么？第一组实验将使用准确性和反应时间的行为测量来推断听者对特定普通话声调（声调3）及其变体（配音）的心理表征的质量。如果学习者对声调3的一种变体的反应不准确或较慢，这可能表明他们的感知存在偏见，可能是由于通常的教学实践只强调一种形式的声调3。第二组实验将检测事件相关电位（ERPs）和对普通话口语的反应行为决策。具体来说，研究将检查N400对单词和非单词的反应，并将其与随后的行为决定进行比较。虽然之前的行为研究表明，学习者对双音节词的音调敏感度严重下降，但这项新研究将提供学习者对音调反应的实时证据，潜在地揭示在行为决策中未被捕捉到的敏感性。研究结果将有助于我们理解成人第二语言学习者词汇声调的习得，并可能有助于改善普通话和其他声调语言的学习和教学。

As the national language of the People's Republic of China, Mandarin Chinese has obvious importance in the modern world. Progress in our understanding of how Mandarin can be learned more effectively is thus of national interest for the United States. Mandarin is a lexical tone language, where pitch cues on syllables distinguish words. Learning lexical tones is known to be difficult for native speakers of English, however, the nature of the difficulty and its causes are not well understood beyond the earliest stages of learning. This project will address two main questions: First, what are adult second language learners' mental representations of Mandarin tone categories like? Second, what is the nature of the difficulty learners have during real-time word recognition?A first set of experiments will use behavioral measures of accuracy and response time to make inferences about the quality of listeners' mental representations for a specific Mandarin tone (Tone 3) and its variants (allotones). If learners' responses are less accurate or slower for one variant of Tone 3, this may indicate a bias in their perception, potentially due to common teaching practices that emphasize only one form of Tone 3. A second set of experiments will examine event-related potentials (ERPs) and behavioral decisions in response to spoken Mandarin words. Specifically, research will examine the N400 response to words and nonwords and compare it to the behavioral decisions that follow. While previous behavioral research suggests learners have severely decreased sensitivity to tones in disyllabic words, this new research will provide real-time evidence of learners' responses to tones, potentially revealing sensitivity that is not captured in behavioral decisions. Results will contribute to our understanding of the acquisition of lexical tones by adult second language learners and may lead to improvements in learning and teaching of Mandarin and other tone languages.