Word Learning in Reading and Language Impairment Subgroups

! 项目总结/摘要 有语言学习障碍的儿童，包括特殊语言障碍和诵读困难， 占公立学校接受特殊教育服务的儿童的57%以上（超过300万儿童）。 虽然他们是独立的障碍，SLI和诵读困难经常共同发生在同一个人。困难 学习新单词被认为是SLI的中心特征，而对于有阅读障碍的儿童， 缺陷通常被视为阅读问题的副产品，而不是原因。然而，大多数研究 SLI和阅读障碍儿童的单词学习涉及异质群体，其中可能包括 很多科摩罗人我们的研究团队是第一个研究SLI儿童的单词学习的团队。 具有良好的文字阅读技能（仅限SLI）和具有良好口语技能的诵读困难儿童 （仅阅读障碍）与SLI和阅读障碍（SLI+DYS）儿童以及具有典型 发展（TD）。我们令人信服的初步结果表明，实验性单词学习 研究和词汇量的标准化测量。首先，尽管在 根据词汇量的标准化测量，只有阅读障碍的儿童在学习上有相当大的困难， 实验性词汇学习范例中的新词汇。第二，仅SLI的儿童表现显著 比那些只有阅读障碍的人更好，尽管得分显着低于那些只有阅读障碍的人， 词汇量的标准化测量。我们的长期目标是更好地理解 词汇学习的实验研究和词汇量的标准化测量，并为临床提供信息。 评估和处理与识字成果有关的词汇学习缺陷的做法。 在这个项目中，我们将测试理论驱动的，临床相关的假设，关于单词学习及其与 与TD相比，SLI、阅读障碍或两者兼而有之（SLI+DYS）儿童的纵向研究中的识字结果 同龄人，从二年级到四年级。具体目标是：（1）检验三个理论驱动的因素，可能解释SLI和 阅读障碍亚组在二年级词汇学习方面的差异：暴露量，教学类型，以及 词汇学习的阶段;（2）确定语言学、一般领域和家庭环境的贡献 解释二年级单词学习个体差异的措施;（3）预测四年级识字结果 从二年级的单词学习措施的等级。这些目标填补了有关机制的理论空白 为SLI和阅读障碍儿童的单词学习缺陷，并解决过去的方法局限性 通过考虑科摩罗并包括精心挑选的具有各种语言的儿童群体， 和读写能力。重要的创新包括连接不同的调查线（实验词） 学习和学术成果; SLI和阅读障碍），对比理论因素与临床 决策（剂量，教学类型，学习阶段），并使用生态有效的附带词- 反映儿童如何从电子媒体中学习单词的学习范式。 !

! Project Summary/Abstract Children with language-based learning disabilities, including specific language impairment (SLI) and dyslexia, comprise over 57% of children receiving special education services in public schools (> 3 million children). Although they are separate disorders, SLI and dyslexia frequently co-occur in the same individuals. Difficulty learning new words is considered a central feature of SLI, whereas for children with dyslexia, vocabulary deficits are typically viewed as a byproduct, rather than a cause, of reading problems. However, most studies of word learning in children with SLI and dyslexia have involved heterogeneous groups, which likely contain many cases of comorbidity. Our research team has been the first to study word learning in children with SLI who have good word reading skills (SLI-only) and children with dyslexia who have good oral language skills (dyslexia-only) as compared to children with both SLI and dyslexia (SLI+DYS) and peers with typical development (TD). Our convincing preliminary results suggest a paradox between experimental word learning studies and standardized measures of vocabulary size. First, despite performing comparably to TD peers on standardized measures of vocabulary size, children with dyslexia-only have considerable difficulty learning novel words in experimental word-learning paradigms. Second, children with SLI-only performed significantly better than those with dyslexia-only despite scoring significantly lower than those with dyslexia-only on standardized measures of vocabulary size. Our long-term goal is to better understand the paradox between experimental word-learning studies and standardized measures of vocabulary size and to inform clinical practice with regard to the assessment and treatment of word-learning deficits as related to literacy outcomes. In this project, we will test theory-driven, clinically relevant hypotheses about word learning and its relation to literacy outcomes in a longitudinal study of children with SLI, dyslexia or both (SLI+DYS) compared to their TD peers, from 2nd to 4th grade. Specific aims are: (1) to test three theory-driven factors that may explain SLI and dyslexia subgroup differences in word-learning at 2nd grade: quantity of exposures, type of instruction, and stages of word learning; (2) to determine the contribution of linguistic, domain-general, and home environment measures to explain individual differences in 2nd grade word learning; and (3) to predict literacy outcomes in 4th grade from measures of word learning in 2nd grade. These aims fill theoretical gaps regarding the mechanisms for word-learning deficits in children with SLI and dyslexia and address methodological limitations of past studies by considering comorbidity and including carefully selected groups of children with a range of language and literacy abilities. Important innovations include connecting disparate lines of inquiry (experimental word learning and academic outcomes; SLI and dyslexia), contrasting theoretical factors with relevance to clinical decision-making (dosage, type of instruction, learning stage), and using an ecologically valid incidental word- learning paradigm that reflects how children learn words from electronic media. !