Auditory Speech Processing in Hearing Impaired Children

描述(申请人提供)：为了学习交流，孩子们必须提取并存储单词的含义和名称。听觉输入主导了早期的词汇学习，这引发了一个关于听力损失(HL)儿童使用听觉/口头交流的词汇发展问题。我们的目标是阐明正常听力(NH)儿童和HL儿童的词汇表征和加工的发展。我们假设HL退化和过滤听觉输入，导致1)不那么丰富的语义范畴知识，2)更具体的语音表征，3)更慢和更低效率的加工。视觉言语在词汇习得中扮演着更为重要的角色，尤其是在语音知识方面。本研究将采用一项使用早期习得的单词和音素的跨通道图像单词任务来评估语义或语音相关的语音单词分心因素对图像命名的影响。如果一个不容忽视的言语干扰因素减慢或加快了图片命名的速度，则其表现被认为反映了理解系统和生产系统之间的信息串扰。串扰模式为假设表现形式和过程的性质提供了基础。分心物的起始点和图片之间的时序关系也是不同的，这种关系被称为刺激开始异步化(SOA)。跨SOA的干扰/促进模式允许人们对词汇、语义或语音加工的时间进程做出推断。已有研究发现，部分HL儿童存在较长时间的语义干扰；2)即使在区分音素的对比下，也缺乏语音效应，这意味着词汇语义激活时间延长，语音表征不那么细粒度或更少基于听觉。然而，以往的研究结果受到以下因素的制约：1)语音激活的时间进程；2)参与者特征和分心物识别/音素辨别能力对命名的影响；3)视觉语音作为语音知识来源的作用。这项拟议的研究纠正了这些限制。我们将使用听觉和视听版本的图词任务来解决三个具体目标：即：1)3-4岁NH儿童干扰/促进模式的发展变化，这将为解释HL儿童的结果提供信息；2)HL儿童干预/促进模式的发展变化；3)仅听觉输入与视听输入对NH&HL儿童干扰/促进模式的影响。通过将UTD和CID的资源结合在一起，我们有一个独特的机会来探索儿童NH&HL的词汇、语义和语音表征的性质以及语音处理系统的动态。这些知识应该导致改进干预策略，扩大HL儿童的社会、教育和职业机会。

DESCRIPTION (provided by applicant): To learn to communicate, children must abstract and store the meanings and names of words. Auditory input dominates this early lexical learning, which raises an issue about lexical development in children with hearing loss (HL) who use aural/oral communication. Our goal is to explicate the development of word representations and processes in normal hearing (NH) children and children with HL. We hypothesize that HL degrades and filters auditory input, resulting in 1) less rich semantic categorical knowledge, 2) less well specified phonological representations, and 3) slower & less efficient processing. Visual speech assumes a more important role in the acquisition of words, particularly for phonological knowledge. The research will apply a cross modal picture-word task using early-learned words and phonemes to assess the influence of semantically- or phonologically-related speech word-distractors on picture naming. If a to-be-ignored speech distractor slows down or speeds up picture naming, performance is assumed to reflect informational crosstalk between the comprehension and production systems. The patterns of crosstalk provide a basis for hypothesizing about the nature of the representations and processes underlying performance. The timing relation between the onsets of the distractors and pictures, termed stimulus onset asynchrony (SOA), also varies. The patterns of interference/facilitation across SOAs allow one to make inferences about the time course of lexical semantic or phonological processing. Previous results found that 1) some children with HL had a protracted time course of semantic interference and 2) a lack of phonological effects even for discriminated phoneme contrasts, implying prolonged lexical semantic activation and less fine grained or less auditorily based phonological representations. Previous results were constrained, however, by an inability to fully map out 1) the time course of phonological activation, 2) the influence of participant characteristics and distractor recognition/phoneme discrimination abilities on naming, and 3) the role of visual speech as a source of phonological knowledge. The proposed research corrects these constraints. We will apply auditory and audiovisual versions of the picture-word task to address 3 specific aims: namely, to determine 1) developmental change in the patterns of interference/facilitation in NH children between 3-4 yrs of age, which will inform interpretation of results in children with HL, 2) developmental change in the patterns of interference/facilitation in children with HL, and 3) the influence of auditory only versus audiovisual input on the patterns of interference/facilitation in children, NH & HL. By joining together the resources of UTD and CID, we have a unique opportunity to explore the nature of lexical semantic and phonological representations and the dynamics of the speech processing system in children, NH & HL. Such knowledge should lead to improved intervention strategies, expanding social, educational, and vocational opportunities for children with HL.