Multimodal Neuroimaging Distinguishes Developmental and Disordered Phenotypes in Speech Sound Disorders

总结 言语产生的发展是一个复杂的过程， 大脑中的躯体感觉、运动和语音系统。减值 这些系统中的任何一个都可能导致语音产生的错误， 不仅对语言发展，而且对语言，识字和社会情感的影响 发展目前诊断言语声音障碍（SSD）的临床实践， 评估其严重性的重点是音素水平的准确性，一个孩子的讲话 制作时，往往以单字标准化评估为基础。然而，纵向 研究表明，仅仅测量音素产生的准确性是不够的， 充分表征SSD。具体来说，那些坚持"发展"的孩子 言语错误（错误类型被认为是年幼儿童的典型错误）更有可能 与那些犯更多非典型错误的人相比， 不一致的错误或声音失真（称为"无序"错误）。在这个项目中，我们将 使用多模态神经成像（功能磁共振成像，结构分析， 脑磁图），以评估先验听觉、躯体感觉、言语 运动和语音网络的5岁儿童与SSD谁使主要 "发展性"言语错误，主要是"紊乱性"言语错误的儿童， 年龄-性别匹配的典型发育（TD）对照组和一组较年轻的TD对照组。 我们预计，"发展"错误将与功能和结构有关， 支持语音处理的大脑机制不成熟。相比之下，"无序" 错误与语音加工中的功能和结构异常有关 区域，沿着这些区域和大脑机制之间的连接中断， 听觉和躯体感觉运动功能。这些研究的结果将提供 一个清晰区分语音背后的大脑机制的基础 疾病，并提供基础，为今后的干预研究，针对 具体网络中的缺陷被确定。

SUMMARY The development of speech production is a complex process that depends on auditory, somatosensory, motor, and phonological (representational) systems in the brain. Impairment in any of these systems could result in errors of speech sound production and have long term consequences not only for speech development but language, literacy, and social-emotional development. Current clinical practice for diagnosis of speech sound disorders (SSDs) and assessment of their severity focuses on the phoneme-level accuracy of a child’s speech production, often based on single word standardized assessment. However, longitudinal studies have shown that measures of phoneme production accuracy alone are insufficient to adequately characterize SSDs. Specifically, children who make persistent “developmental” speech errors (error types considered to be typical errors in younger children) are more likely to demonstrate a resolution to their SSD compared to those who make more atypical errors, inconsistent errors, or distortion of sounds (termed “disordered” errors). In this project, we will use multimodal neuroimaging (functional magnetic resonance imaging, structural analysis, and magnetoencephalography) to assess engagement of a priori auditory, somatosensory, speech motor and phonological networks in 5-year-old children with SSDs who make predominately “developmental” speech errors, children who make predominately “disordered” speech errors, age- gender-matched typically developing (TD) controls, and a cohort of younger TD controls. We expect that “developmental” errors will be associated with functional and structural immaturity in brain mechanisms supporting phonological processing. In contrast, “disordered” errors will be associated with functional and structural abnormalities in phonological processing regions, along with disrupted connectivity between these regions and brain mechanisms for auditory perception, and somatosensory-motor function. The results of these studies will provide a foundation by which to clearly differentiate the brain mechanisms underlying speech sound disorders and provide a foundation on which to build for future intervention studies targeting the specific networks in which deficits are identified.