Brain Mechanisms underlying skilled reading in deaf and hard of hearing (DHH) children with different communication modes

项目总结 许多聋重听(DHH)儿童在阅读方面有困难，有些儿童的阅读障碍很严重 孩子随着年龄的增长而增加。尽管如此，我们对成功阅读的大脑机制知之甚少。 DHH儿童，或者对某些机制的依赖是否因沟通模式而异。我们不知道为什么 一些东华三院的孩子是好读者，而另一些则不是。我们利用了巨大的个体差异 阅读技能，以确定更好的阅读如何依赖于不同的机制，以及这是否因 沟通方式。该项目使用功能性磁共振成像(FMRI)对10至15岁的儿童进行听力检查。 手语占主导地位、口语占主导地位或双峰的儿童以及DHH儿童 语言。创新的纵向方法在两年后对儿童进行跟踪调查，并允许调查 阅读能力的提高与大脑随时间的变化以及这种变化是否随年龄变化有关。最重要的理论是 阅读习得是三角模型，它有三个表征系统，包括拼法(拼写)、 语音(声音)和语义(意义)，以及在这些系统之间映射的路径。一个 该项目的基本优势是将成熟的三角形模型扩展为第一个 DHH儿童阅读的神经认知模型。我们的项目测试三角模型的关键假设，包括 正字法表征的性质、正字法到语音映射和正字法到语义的关系 映射。我们测试了这些成分与DHH儿童随时间的技能和发育变化的关系 具有不同的通信模式。该项目的另一个创新方面是使用“本地化”功能磁共振成像任务 独立识别语音过程中颞顶皮质中与语音机制相关的区域 阅读、手语和口语音系学，以及中间与语义机制相关的区域 颞叶回。独立本地化程序任务的使用为我们理解 DHH儿童熟练阅读的潜在神经机制。孩子们还完成了两次阅读功能磁共振成像 任务，一项涉及押韵判断，另一项涉及对视觉呈现的单词的意义判断。不 我们只研究语音和语义机制与阅读的关系，但我们的新方法还 检查这些区域与参与正字法处理的梭形皮质的连通性。除 FMRI测量，所有儿童都完成了广泛的最先进的行为测试 语言、口语和阅读。该项目的重点是单词解码的个体差异，因为这是 这是阅读的关键组成部分，但我们也考察了阅读理解中的行为差异。

PROJECT SUMMARY Many deaf and hard-of-hearing (DHH) children struggle with reading and the severity of the impairment for some children increases with age. Despite this, we know very little about the brain mechanisms for successful reading in DHH children, or whether reliance on certain mechanisms differs with communication mode. We do not know why some DHH children are good readers and other are not. We take advantage of the large individual differences in reading skill to determine how better reading relies on different mechanisms and whether this varies with communication modes. This project uses functional magnetic resonance imaging (fMRI) in 10- to 15-year-old hearing children as well as in DHH children with predominant signed language, predominant oral language, or bimodal language. The innovative longitudinal approach follows children two years later and allows an investigation of how reading gains are related to brain changes over time and whether this varies with age. The overarching theory of reading acquisition is the Triangle Model which has three representational systems, including orthography (spelling), phonology (sound) and semantics (meaning), as well as pathways for mapping between these systems. A fundamental strength of this project is extending the well-developed Triangle Model to formulate the first neurocognitive model of reading in DHH children. Our project tests critical assumptions of the Triangle Model including the nature of orthographic representations, of orthographic to phonological mapping and of orthographic to semantic mapping. We test how these components are related to skill and developmental change over time in DHH children with different communication modes. Another innovative aspect of the project is the use of `localizer' fMRI tasks to independently identify regions associated with phonological mechanisms in temporo-parietal cortex during speech reading, signed language and spoken phonology, as well as regions associated with semantic mechanisms in middle temporal gyrus. The use of independent localizer tasks provides fundamental advances in our understanding of the underlying neural mechanisms involved in skilled reading in DHH children. Children also complete two reading fMRI tasks, one involving rhyming judgments and the other involving meaning judgments to words presented visually. Not only do we examine how phonological and semantic mechanisms are related to reading, but our novel approach also examines connectivity of these regions with fusiform cortex involved in orthographic processing. In addition to the fMRI measures, all children complete an extensive battery of state-of-the-art behavioral tests measuring signed language, oral language and reading. The focus of the project is on individual differences on word decoding as this is a critical building block to reading, but we also examine behavioral differences in reading comprehension.