Development of Word-Level Reading and the N400 Component of the ERP

描述（由申请人提供）：根据美国政府的统计数据，只有大约三分之一的美国四年级学生阅读达到熟练水平。四年级是小学的关键一年，因为课程通常要求学生从学习如何阅读的基础知识转向以成人的方式使用既定的阅读技能，以获得和建立新的知识。行为数据表明，上下文无关的识别简单，高频词是自动的四年级在典型的发展中的读者，但神经数据是稀缺的。这项研究对三、四、五年级学生进行了研究，研究对象包括各种阅读技能（拼写、语音、语义和理解）的标准化行为测量，以及神经文字处理的测量，即事件相关电位（ERP）波形的N400分量。在以前的成人研究中，N400已经被证明可以索引词汇语义和更高层次的文字处理方面。这里，N400将被记录为简单的真实的单词（例如，床），伪词（例如，BEM），不可发音的字母串（例如，MBE），以及字母状刺激的字符串（例如，BEM）以列表形式呈现。据预测，只有正字法和语音学上的法律的刺激（单词和假词）将引起N400在年龄较大的儿童/更好的读者，而所有类型的刺激可能会引起N400在年幼的儿童/较穷的读者谁还没有自动化较低级别的过程相关的阅读;与此一致，大脑和行为措施之间的相关性预计会随着发展时间的变化。这种模式的研究结果表明，神经认知的文字处理系统，是更开放的语言的可能性和较少的选择性处理字符串作为候选字在年幼的儿童/较贫穷的读者，表明一些儿童在小学后期确实可能还没有处理单词和单词样的刺激类似于成人。这些见解可能对课堂教学产生影响，特别是对许多在小学后期面临风险和难以阅读的儿童。从长远的角度来看，这种对儿童和成人的神经和行为测量的文字处理研究将提供收敛和限制性的证据，从而更好地，多层次地理解作为阅读技能核心的文字处理系统的发展。 公共卫生相关性：阅读能力差的儿童有可能辍学，最终学业失败，导致其他公共卫生风险。从大脑和行为两个方面对阅读技能的发展进行基础研究，可以更好地理解阅读技能的发展过程。这种理解的科学进步最终可以在课堂上用于更好的教学和学习，并为贫困读者设计补救计划。

DESCRIPTION (provided by applicant): According to U.S. Government statistics, only about one-third of American fourth-graders are reading at a proficient level. Fourth grade is a pivotal year in elementary school as the curriculum typically requires students to shift from learning the basics of how to read to using established reading skills in an adult-like manner, to gain and build new knowledge. Behavioral data suggest that context-free recognition of simple, high frequency words is automatic by the fourth grade in typically developing readers but neural data are scarce. The proposed research with groups of third-, fourth-, and fifth-graders uses both standardized behavioral measures of various reading skills (orthographic, phonological, semantic, and comprehension) and a measure of neural word processing, the N400 component of the event-related potential (ERP) waveform. In previous studies with adults, the N400 has been shown to index both lexicosemantic and higher-level aspects of word processing. Here, the N400 will be recorded to simple real words (e.g., bed), pseudowords (e.g., bem), nonpronounceable letter strings (e.g., mbe), and strings of letter-like stimuli (e.g., BEM) presented in list form. It is predicted that only orthographically and phonologically legal stimuli (words and pseudowords) will elicit an N400 in older children/better readers, while all types of stimuli may elicit an N400 in younger children/poorer readers who have not yet automatized lower-level processes related to reading; consistent with this, correlations between the brain and behavioral measures are predicted to change over developmental time. This pattern of findings would indicate a neurocognitive word processing system that is more open to linguistic possibility and less selective in processing strings as word candidates in younger children/poorer readers, showing that some children in late elementary school indeed may not yet be processing word and word-like stimuli similarly to adults. Such insights might have implications for teaching and learning in the classroom, particularly for the many children at risk and struggling to read in late elementary school. In a broad, long-term view, such investigations of word-level processing using both neural and behavioral measures in children and adults will provide converging and constraining evidence that will lead to a better, multilevel understanding of the development of word processing systems that are at the core of reading skills. PUBLIC HEALTH RELEVANCE: Children who are poor readers are at risk for disengagement from school and eventual school failure, leading to other public health risks. Basic research that investigates the development of word reading skills in terms of both brain and behavior, as proposed here, can lead to a better understanding of the developmental course of reading skills. Such scientific advances in understanding can eventually be used in the classroom for better teaching and learning, and for design of remediation programs for poor readers.