Articulation and representation of second language speech sounds

该奖项是美国国家科学基金会社会、行为和经济科学博士后研究奖学金（SPRF）计划的一部分。SPRF计划的目标是为学术界、工业界或私营部门和政府的科学事业准备有前途的早期职业博士级科学家。SPRF奖励包括在知名科学家的赞助下进行为期两年的培训，并鼓励博士后进行独立研究。美国国家科学基金会寻求促进科学界各阶层的科学家，包括那些未被充分代表的群体的科学家，参与其研究项目和活动；博士后阶段被认为是实现这一目标的一个重要的专业发展阶段。每个博士后必须解决各自学科领域的重要科学问题。在北卡罗莱纳州立大学杰夫·米尔克博士的赞助下，这项博士后奖学金支持一位研究第二语言学习者如何表达第二语言语音的早期职业科学家。具体来说，这些研究考察了说话者是否会发出与母语相同的第二语言语音，以及学习者的生成策略是否会因语音的性质而有所不同。因此，本研究使用第二语言语音的超声、声学和感知数据来研究辅音和元音类别转移的本质，以努力描述语音的声学和发音目标。更多关于第二语言发音的研究对于改善与语音教学中使用技术（特别是超声和声学技术）相关的教学实践至关重要，这项研究为非母语语音对比的习得提供了声学、发音和感知里程碑的信息。定义语音表示法的困难来自于辅音和元音不同的语音性质。辅音可以通过收缩位置和收缩程度来定义，因此手势模型非常适合解释涉及辅音的语音过程。另一方面，与辅音相比，元音是用相对开放的声道发出的，因此不容易通过发音目标来定义。本项目中包含的实验比较了L2类别形成的手势模型和声学模型的假设。前两个实验使用声学、超声波和感知数据来检验母语英语使用者如何产生和感知第二语言普通话摩擦音和元音，并将其与母语摩擦音和元音进行比较。第二两个实验再次使用声学、超声波和感知数据，对比母语英语使用者如何产生和感知第二语言韩语摩擦音和元音。记录学习者在初级、早期、中期和后期的学习阶段。这些实验有助于第二语言范畴形成理论的研究，这些理论对辅音和元音的认知表征具有重要意义。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award was provided as part of NSF's Social, Behavioral and Economic Sciences Postdoctoral Research Fellowships (SPRF) program. The goal of the SPRF program is to prepare promising, early career doctoral-level scientists for scientific careers in academia, industry or private sector, and government. SPRF awards involve two years of training under the sponsorship of established scientists and encourage Postdoctoral Fellows to perform independent research. NSF seeks to promote the participation of scientists from all segments of the scientific community, including those from underrepresented groups, in its research programs and activities; the postdoctoral period is considered to be an important level of professional development in attaining this goal. Each Postdoctoral Fellow must address important scientific questions that advance their respective disciplinary fields. Under the sponsorship of Dr. Jeff Mielke at North Carolina State University, this postdoctoral fellowship award supports an early career scientist examining how second language learners articulate second language speech sounds. Specifically, these studies examine whether speakers produce second language speech sounds the same as their first language speech sounds, and whether learners’ production strategies differ depending on the nature of the speech sounds. As such, this research uses ultrasound, acoustic, and perception data of second language speech to look at the nature of category transfer of both consonants and vowels, in an effort to describe the acoustic and articulatory targets of speech sounds. More research about second language pronunciation is vital to improve pedagogical practices related to using technology in pronunciation instruction (specifically ultrasound and acoustic technologies), and this research provides information about acoustic, articulatory, and perceptual milestones for the acquisition of non-native sound contrasts.A difficulty for defining the representation of speech sounds arises from the different phonetic nature of consonants and vowels. Consonants are definable by their constriction location and constriction degree, and thus gestural models are well-suited to explaining phonological processes involving consonants. Vowels, on the other hand, are produced with a relatively open vocal tract compared to consonants, and are therefore less easily definable by their articulatory targets. The experiments included in this project compare hypotheses of gestural and acoustic models of L2 category formation. The first two experiments use acoustic, ultrasound, and perception data to examine how L1 English speakers produce and perceive L2 Mandarin fricatives and vowels compared to L1 fricatives and vowels. The second two experiments examine how L1 English speakers produce and perceive L2 Korean fricatives and vowels compared to L1 fricatives and vowels, again using acoustic, ultrasound, and perception data. Learners in beginning, early-intermediate, and late-intermediate learning stages are recorded. These experiments contribute to theories of L2 category formation, which importantly have implications about the cognitive representation of consonants and vowels.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.