NEUROBEHAVIORAL DEVELOPMENT--NORMAL, LI & DEAF CHILDREN

描述(改编自调查人员的摘要)：提案 广泛的目标是描述分化的时间过程 神经系统在正常情况下对语言和感觉加工很重要 发育中的3个月至8岁的儿童。拟议的研究将 测试以下假设--显示最大程度的 发育可塑性在更长的时间段内发生分化 那些不太容易修改的。语言高危儿童的研究 语言障碍(LTS)和诊断为语言障碍的儿童 将观察到减损(LI)。来检验这样一种假设 在多个系统中可以导致LI，可以预测LI，并且 被干预计划改变了。先天聋儿的研究 习得ASL探索特定类型感觉输入的作用 被认为是语言系统发展的中心 麦片。像往常一样，事件相关电位会被记录在几个大脑区域，李， 失聪儿童处理刺激旨在激活特定方面的 感觉和语言功能。我们将检验六个具体的假设： (1)到了30个月，不同的神经系统在词汇和词汇之间起中介作用 语法处理；这些系统表现出越来越大的差异性 直到8年。(2)儿童会表现出语音的事件相关电位证据 在6个月时启动，但相关的神经系统将继续 在整个童年中期发展。(3)加工过程中的重要系统 快速呈现的非语言听觉刺激沿 比语言相关的神经系统和背部更早的时间进程 视觉通路比腹侧通路分化的时间更长 视频流。(4)最早答复的时间和组织 用言语和非言语刺激来预测哪些学习障碍儿童会赶上 这将成为李的未来。(5)在一些人中，李产生于 在感觉处理方面的缺陷，而在其他方面的缺陷是 语言上的。(6)语言系统在生物上的不变作用 左脑在口语和手语上都遵循类似的时间进程 语言。

DESCRIPTION (adapted from the investigator's abstract): The proposal's broad goals are to characterize the time-course of differentiation of neural systems important in language and sensory processing in normally developing children ages 3 months to 8 years. The proposed research will test the following hypothesis--systems that display the greatest degree of developmental plasticity differentiate over longer time periods than do those that are less modifiable. Studies of children at risk for language impairment (Late Talkers, LTs) and children with a diagnosis of language impairment (LI) will be observed. to test the hypothesis that alterations in multiple systems can lead to LI, can be predictive of LI, and are altered by intervention programs. Studies of congenitally deaf children acquiring ASL explore the role of specific types of sensory input hypothesized to be central to the development of the language systems of the bran. ERPs will be recorded over several brain regions as normal, LI, and deaf children process stimuli designed to activate specific aspects of sensory and language functions. Six specific hypothesis will be tested: (1) By 30 months, distinct neural systems mediate lexical versus grammatical processing; these systems display increasing differentiation until 8 years. (2) Children will show ERP evidences of phonological priming at 6 months, but the associated neural systems will continue to develop throughout middle childhood. (3) Systems important in processing rapidly presented non-language auditory stimuli differentiate along an earlier time-course than language-relevant neural systems, and the dorsal visual pathway differentiates along a longer time-course than the ventral visual stream. (4) The timing and organization of the earliest responses to speech and non-speech stimuli predict which LT children will catch up and which will go on to become LI. (5) In some individuals, LI arises from deficits in sensory processing while in others the deficit is specifically linguistic. (6) The biologically invariant role of language systems in the left hemisphere follows a similar time-course for both spoken and signed languages.