WORD LEARNING & MEMORY FUNCTIONS IN CHILDREN WITH AUTISM

本文研究了语法知识和参考显著性如何指导自闭症的早期世界学习，自闭症是一种以显著语言缺陷为特征的发育障碍。单词学习的过程需要孩子将单词或单词部分（语素）的共现词与其含义相匹配。这种匹配需要整合来自语言、社会和现实环境的多种概率线索，因此可能依赖于工作记忆。矛盾的是，发育正常的儿童有限的短期言语记忆特征可能会改善这种对共现现象的分析。他们对言语字符串的有限记忆可能会将注意力集中在更小的元素上，而这些元素在语言中是语法信息最重要的意义承载单位。相比之下，高效的口头短期记忆和有限的工作记忆模式可能会阻碍规则学习，导致语言延迟。这种模式被认为是自闭症儿童的特征，因此可能有助于解释他们的语言缺陷。目前的研究通过一个单词学习任务来检查自闭症患者的早期语言，该任务包括语法和参考线索对一个新单词的变化。该任务将子分类分为计数类和质量类，与正常发展中的单词学习高度相关。并比较了社会和非社会参照线索的影响。为了评估假设的记忆缺陷模式是否与词汇任务的表现相关，研究人员对工作记忆和短期语音记忆进行了测试。参与者将是20名自闭症儿童，20名语言和时间年龄匹配的唐氏综合症儿童，以及20名语言智力年龄匹配的正常对照。研究结果将有助于我们理解自闭症的语言发展，从而对干预具有重要意义。研究结果也将加深我们对工作记忆和短期语音记忆在语言发展中的作用的理解。

This dissertation examines how grammatical knowledge and referential salience guide early world learning in autism, a developmental disability characterized by significant language deficits. The process of word learning requires a child to match co-occurrences of words of parts of words (morphemes) and their meanings. This matching demands the integration of multiple, probabilistic cues from the linguistic, social, and real-world contexts, and thus may depend on working memory. Paradoxically, the limited short-term verbal memory characteristic of typically-developing children may improve this analysis of co- occurrences. Their limited memory for verbal strings may focus attention on smaller elements, which in language are the most important meaning- bearing units for grammatical information. In contrast, a pattern of efficient verbal short-term memory and limited working memory could impede rule-learning, leading to language delays. This pattern is thought to characterize children with autism, and thus may help explain their language deficits. The present study examines early language in autism using a word-learning task that varies both grammatical and referential cues to a novel word. This task, which examine sub-categorization into count and mass non classes, is highly relevant to word learning in normal development. The influence of social and non-social referential cues is also compared. Working and short-term phonological memory are tested in order to assess whether the hypothesized pattern of memory deficits is correlated with performance on the lexical task. Participants will be 20 children with autism, 20 verbal and chronological age-matched children with Down syndrome, and 20 verbal mental age-matched normal controls. Results will inform out understanding of language development in autism and thus have important implications for intervention. Results will also heighten our understanding of the roles that working and short-term phonological memory play in language development.