发展性阅读障碍（Developmental Dyslexia, DD）是一种最常见的儿童青少年学习障碍，严重阻碍个体的发展，给家庭、社会和国家带来沉重压力。早期诊断和干预对DD的矫治至关重要，但迄今仍未找到可靠的早期生物学诊断指标。本项目拟从学习阅读障碍这个DD最核心的问题切入，以近期研究及本课题组对成人和儿童（特别是学前儿童）系列研究发现的左半球N170的选择性这个测量书面文字加工专家化的可靠电生理指标为基础，提出以N170作为汉语DD早期生物学诊断指标的假设，采用聚合交叉研究设计，系统考察7-10岁汉语DD儿童书面文字加工N170的发展特点及发展进程，检验学前5-6岁记录的N170反应对儿童阅读发展和阅读障碍的早期预测作用。本项目不仅可以系统评估N170可以作为一个DD早期诊断生物学标志的潜力，而且将为深入理解DD（特别是汉语DD）学习阅读困难的认知神经机制提供新的证据。

Developmental dyslexia (DD) is the most common learning disability in children and adolescents. This disorder severely hinders individual's development and can be an economic burden on family, society and country. Notably, early diagnosis and intervention is critical for improving the reading ability of dyslexic children. However, there is still no reliable biological marker for early diagnosis of dyslexia. The disability of learning to read is the core and most obvious problem of children with DD. Recently, a series of our own studies and those of others on adults and children especially preschool children, revealed that an event-related potential component (termed as N170) is a reliable electrophysiological marker for expertise in reading words. Thus, the current project proposes a novel hypothesis that the N170 component is an objective biological marker for the early diagnosis of Chinese dyslexic children. Through an aggregate cross-design, the project aims to investigate the development of N170 expertise for written words in Chinese dyslexic children of 7 to 10 years. And further, this project will examine how a kindergarten (5 to 6 years) student's N170 response to written words predicts their subsequent reading ability in the first and second grades, together with other typical behavioral predictions from kindergarten. As a benchmark to our predictions based on both N170 and typical behavioral measures, we will contrast this model against prediction based on behavioral measures alone. This project will not only systematically evaluate the potential of N170 as a biological marker for early diagnosis of Chinese children with DD; but also provide new evidence for a deep understanding the cognitive and neural mechanism of the disability of learning to read in dyslexic especially Chinese children.