DEVELOPMENT OF SKILLED READING: FMRI STUDIES

描述（由申请人提供）：本提案的重点是在阅读技能的发展习得过程中必须磨练的正字法和语音过程的神经基础。当一个年轻的读者获得书面文字的经验时，这些过程的变化就会随着发展而出现。从行为上看，成年人在处理字母比视觉上相似的字母物体，以及合法字母串比非字母串或非法字母串方面表现出优势（即速度和/或准确性提高），但在儿童中不那么明显。这种处理优势表明，不断增加的经验使读者能够提取有关构成字母和单词的视觉特征的具体、正字法信息。与此同时，大量证据表明语音加工为阅读发展提供了重要的支持，其与正字法过程的相互作用随着技能的发展而变化。关于阅读技能的发展习得如何与大脑中假定的正字法和语音处理区域相关的信息，应该为理解典型（和非典型）阅读发展提供重要的神经生物学基础，并为未来更有针对性的教育和补救策略提供信息。第一个具体目标是测试大脑的视觉处理区域将随着阅读技能的发展而显示出越来越多的专业化的假设。第二个具体目的是验证一个假设，即随着阅读技能和正字法专业化的提高，对语音加工机制的依赖会减少。第三个具体目标是使用功能连接MRI和图论分析来表征成人和儿童阅读网络的发展差异。其他建议的分析包括纵向成分，其中一组受试者在五年的时间内重复扫描，使用多元方法结合阅读/认知技能与成像和扫描仪内性能参数的稳定测量来探索个体差异，以及探索发育性差异。公共卫生相关性：本建议侧重于正字法和语音过程的神经基质，这些过程必须在阅读技能的发展习得中得到磨练。关于阅读技能的发展习得如何与大脑中假设的正字法和语音处理区域相关的信息，应该为理解典型（和非典型）阅读发展提供重要的神经生物学基础，这些基础知识可以用来为更有针对性的未来教育和补救策略提供信息。

DESCRIPTION (provided by applicant): This proposal focuses on neural substrates of orthographic and phonological processes that must be honed in the developmental acquisition of reading skill. Changes in these processes emerge through development as a young reader gains experience with written words. Behaviorally, adults show processing advantages (i.e. increased speed and/or accuracy), less evident in children, for letters over visually similar letter-like objects, and for legal letter strings over non-letter strings or illegal letter strings. This processing advantage suggests that increasing experience enables a reader to extract specific, orthographic information about the visual features that form letters and words. In concert, extensive evidence suggests that phonological processing provides important support for reading development, and that its interplay with orthographic processes varies as skill develops. Information about how the developmental acquisition of reading expertise relates to putative orthographic and phonological processing regions in the brain should provide an important neurobiological foundation for understanding typical (and atypical) reading development, and inform more targeted future education and remediation strategies. The first specific aim tests the hypothesis that visual processing regions of the brain will show increasing specialization with the developmental acquisition of reading skill. The second specific aim tests the hypothesis that concomitant with increasing reading skill and orthographic specialization comes decreasing reliance on phonological processing mechanisms. The third specific aim uses functional connectivity MRI and graph theory analysis to characterize developmental differences in reading networks between adults and children. Additional proposed analyses include a longitudinal component where a cohort of subjects have repeated scans over a five year period, exploration of individual differences using a multivariate approach combining stable measures of reading/cognitive skill with imaging and in-scanner performance parameters, and an exploration of developmental sex differences. PUBLIC HEALTH RELEVANCE: This proposal focuses on neural substrates of orthographic and phonological processes that must be honed in the developmental acquisition of reading skill. Information about how the developmental acquisition of reading expertise relates to putative orthographic and phonological processing regions in the brain should provide an important neurobiological foundation for understanding typical (and atypical) reading development, and this basic knowledge can be used to inform more targeted future education and remediation strategies.