Constraints on Phonological and Morphological Development

语音和形态发展的限制

• 批准号: 8308117
• 负责人: STEFANIE SHATTUCK-HUFNAGEL
• 金额: $ 29.85万
• 依托单位: MASSACHUSETTS INSTITUTE OF TECHNOLOGY
• 依托单位国家: 美国
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-06-01 至 2013-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8308117
• 关键词: 2 year old; Acoustics; Address; Adult; Case Study; Categories; Child; Cues; Databases; Development; Developmental Process; Diagnosis; Ensure; Foundations; Frequencies; Genetic Transcription; Gestures; Goals; Health; Hylobates Genus; Impairment; Individual; Intervention; Knowledge; Language; Length; Link; Masks; Measures; Methods; Modeling; Morphology; Neighborhoods; Parents; Pattern; Persons; Phonetics; Population; Positioning Attribute; Process; Production; Research; Shapes; Signal Transduction; Speech; Staging; Structure; Testing; Time; Variant; Voice; Work; base; contextual factors; density; design; diagnosis design; insight; lexical; novel strategies; phonology; research study; tool

DESCRIPTION (provided by applicant): Children's early word productions are often inconsistent in form, showing apparent between-speaker and within-speaker variability in phonological and morphological shape. Recent results show more adult-like productions in certain contexts, suggesting that children's phonological and morphological representations are more robust than often assumed. Previous acoustic/phonetic studies have also shown that children sometimes make systematic acoustic or gestural feature contrasts not perceived as such by adults (covert contrasts). However, research on such covert contrast has been limited to a few case studies. Little is therefore known about the extent of these processes across young, normally developing learners, nor about how this relates to early variability in natural speech. This proposal addresses this problem by using acoustic and articulatory measures to test the hypothesis that many of children's early phonological and morphological representations are more adult-like than they appear. To investigate this issue we draw on recent theoretical and empirical work on adult speech, where variability in production has been analyzed in terms of individual acoustic/articulatory cues to grammatical feature contrasts. However, most of this research to date has focused on the beginnings of words (onsets): very little is known about how adults or children produce contrasts at the ends of words, where languages like English encode important grammatical morphemes. We therefore extend and compare previous findings to the acoustic/phonetics of child- directed speech (by adults) and to child speech, focusing on the question of when and how children acquire word-final (coda) consonants. To do this we first carry out detailed acoustic analyses of existing adult and child speech corpora, focusing on the production of simple non-inflected and inflected words (e.g., dig, digs). We then compare these results with those of 2-year-old's speech productions under more controlled experimental conditions. The goal is to better understand the principles that underlie phonological and morphological variation in child speech. We hypothesize that between-speaker variability will occur most often for feature contrasts that are signaled by multiple articulatory gestures and acoustic cues (e.g., the voicing of word-final consonants), where developing speakers may initially implement different feature cues. In contrast, we hypothesize that within- speaker variability will be highly predictable and context dependent (e.g., sensitive to word complexity and position within the utterance), reflecting constraints on phonological form. The results will provide a framework for better understanding children's early knowledge of phonological and morphological structure, and will lay the foundation for a developmental model of language planning. This will have implications for more accurate diagnosis and design of interventions for both child and adult populations with language impairments. PUBLIC HEALTH RELEVANCE: The findings from this research will reveal much about the structure of children's early phonological and morphological representations, and how these develop over time. In so doing, they will provide insight into the mechanisms underlying variability in children's productions, and the possible impact of input, complexity and contextual factors in understanding between-speaker and within-speaker variability in language production. These findings will lay the foundation for constructing a developmental model of language planning, providing a framework for designing more effective tools for diagnosing and treating aspects of language impairment.

描述(申请人提供)：儿童早期的单词发音在形式上往往不一致，表现出说话人之间和说话人内部在语音和形态上的明显差异。最近的研究结果表明，在某些特定的背景下，儿童的语音和形态表征更像成人，这表明儿童的语音和形态表征比通常认为的更健壮。以前的声学/语音研究也表明，儿童有时会进行成年人没有察觉的系统性声学或手势特征对比(隐蔽对比)。然而，对这种隐蔽对比的研究仅限于少数几个案例研究。因此，关于这些过程在年轻的、正常发育的学习者中的程度，以及这与自然语言的早期可变性之间的关系，我们知之甚少。这项建议通过使用声学和发音测量来测试假设，即许多儿童早期的语音和形态表征比看起来更像成年人，从而解决了这个问题。为了探讨这一问题，我们借鉴了最近关于成人言语的理论和实证研究成果，这些研究从个别声学/发音线索到语法特征对比的角度分析了产出的可变性。然而，到目前为止，这项研究的大部分都集中在单词的开头：人们对成年人或儿童如何在词尾产生对比知之甚少，因为像英语这样的语言编码重要的语法语素。因此，我们将先前的研究结果扩展到儿童发音(成人)和儿童发音的声学/语音学，重点研究儿童何时以及如何获得词尾辅音的问题。为了做到这一点，我们首先对现有的成人和儿童语音语料库进行详细的声学分析，重点是产生简单的非屈折和屈折的单词(例如，DIGH，DUDS)。然后，我们将这些结果与2岁儿童在更受控制的实验条件下的语音产出进行了比较。我们的目标是更好地理解儿童语言中语音和形态变异背后的原理。我们假设，对于由多个发音手势和声学提示(例如，词尾辅音的发音)表示的特征对比，说话人之间的可变性将最频繁地发生，其中发展中的说话人最初可能实现不同的特征提示。相反，我们假设说话人内部的可变性将是高度可预测的和上下文相关的(例如，对单词的复杂性和在话语中的位置敏感)，反映了对语音形式的限制。研究结果将为更好地理解儿童早期的语音和形态结构知识提供一个框架，并将为语言规划的发展模式奠定基础。这将对更准确地诊断和设计针对语言障碍儿童和成人人口的干预措施具有重要意义。与公共健康相关：这项研究的发现将揭示儿童早期语音和形态表征的结构，以及这些结构是如何随着时间的推移而发展的。通过这样做，他们将深入了解儿童语言输出中潜在的可变性的机制，以及输入、复杂性和语境因素在理解语言输出中说话者之间和说话者内可变性方面可能产生的影响。这些发现将为构建语言规划的发展模式奠定基础，为设计更有效的语言障碍诊断和治疗工具提供框架。