Audiovisual processing in children with developmental language disorder

项目概要-发展性语言障碍的视听处理 新兴的发展研究表明，视觉言语线索促进获得 语言的重要组成部分，如音素和单词，并塑造两者的发展 言语产生和言语感知。由于视觉语言线索影响多个方面， 典型的语言习得，以及更普遍的言语感知，我们问是否有障碍， 视觉发音运动的处理和/或整合这些运动的困难 并发听觉言语可能是在发育性听力障碍儿童中观察到的一些缺陷的基础。 语言障碍（DLD）。 DLD的特点是在缺乏容易识别的语言的情况下难以获得语言 原因，如听力障碍，坦率的神经系统疾病，或低非语言智力。它影响 在美国，大约7%的学龄前儿童患有这种疾病，并且通常是终身的疾病。早期研究 提示DLD患者至少在视听处理的某些方面受损，但病因仍然存在 未知 在这个项目中，我们建议检查DLD儿童及其典型发育（TD） 对等一组对于正常视听处理至关重要的机制。这些机制包括 （1）听觉和视觉模态对事件间时间关系的敏感性; (2)语音相关视觉特征的感觉编码，即形状和运动;（3）分配 注意复杂视觉对象的特征;（4）听觉/发音的知识 语音的对应。在同一组儿童中研究这些机制， DLD和TD将提供有关视听障碍的异质性/同质性的信息， DLD和损害的影响，在只有一个与几个机制对视听语言的使用。我们 联合收割机将行为测量与ERP和EEG数据分析相结合， 每个机制参与的进程。 了解DLD视听加工困难的原因，对临床有重要意义 影响视听整合通常促进了一些语言技能，这些技能在学习中受到损害。 DLD，如语音和词汇处理和噪声中的语音感知。因此，确定 阻止DLD儿童使用视觉言语线索的机制，以及他们的TD同龄人 并且使他们康复可能会导致这些语言技能的改善。此外，本发明还 比较典型和非典型儿童视听整合的神经过程， 语言能力为神经网络的发展提供了一个独特的窗口， 听觉和视觉模态及其对正常和紊乱的语言功能的影响。

Project Summary – Audiovisual processing in developmental language disorder Emerging developmental studies show that visual speech cues facilitate the acquisition of important building blocks of language, such as phonemes and words, and shape the development of both speech production and speech perception. Because visual speech cues influence multiple aspects of typical language acquisition, and speech perception more generally, we ask whether impairment in the processing of visual articulatory movements and/or difficulty in integrating such movements with concurrent auditory speech may underlie some of the deficits observed in children with developmental language disorder (DLD). DLD is characterized by difficulties in acquiring language in the absence of an easily identifiable cause, such as hearing impairment, frank neurological disorders, or low non-verbal intelligence. It affects approximately 7% of preschool children in the US and is typically a life-long condition. Earlier studies suggest that at least some aspects of audiovisual processing are impaired in DLD, but the causes remain unknown. In this project, we propose to examine in children with DLD and their typically developing (TD) peers a set of mechanisms that are essential for normal audiovisual processing. These mechanisms include the following: (1) sensitivity to temporal relationships between events in auditory and visual modalities; (2) sensory encoding of speech-relevant visual features, namely shape and motion; (3) allocation of attention to features of complex visual objects; and (4) knowledge of auditory/articulatory correspondences for speech sounds. Examining these mechanisms in the same groups of children with DLD and TD will provide information about both the hetero/homogeneity of audiovisual impairments in DLD and the effects of impairment in just one vs. several mechanisms on audiovisual language use. We combine behavioral measures with ERP and EEG data analyses in order to map the nature of neural processes engaged by each mechanism. Understanding the causes of audiovisual processing difficulties in DLD has significant clinical implications. Audiovisual integration normally facilitates some of the linguistic skills that are impaired in DLD, such as phonological and lexical processing and speech-in-noise perception. Hence, identifying the mechanisms that prevent children with DLD from using visual speech cues as well as their TD peers do and rehabilitating them could potentially lead to improvements in these linguistic skills. Additionally, comparing the neural processes underlying audiovisual integration in children with typical and atypical language ability provides a unique window into the development of the neural networks connecting auditory and visual modalities and their impact on normal and disordered language function.