Neurocognitive Development in Typically Developing, At-Risk, and ESL Children

描述（由申请人提供）：项目总结：我们的主要目标是描述语言处理和语言中心的注意力和感觉技能中重要的神经系统和子系统的特性、发育时间历程和相对可塑性（可修改性/脆弱性）。在3-17岁的儿童中，我们将获取行为数据、事件相关脑电位（ERPs），并在6-17岁的儿童中获取大脑的结构和功能磁共振图像（fMRI），以表征参与者在执行旨在操纵感觉、注意力和语言处理的特定方面的任务时神经活动的时间和位置。我们将检验以下假设：(1)在语义处理中重要的系统比在语法和语音处理中重要的系统成熟得早；(2)与高SES儿童相比，低SES儿童发育时间较长的系统更不成熟。鉴于听觉注意和快速听觉处理在语言技能中的核心作用，我们还将评估以下假设：(3)集中听觉注意的神经机制的某些方面至少要到10岁才成熟；(4)这些系统在低社会地位儿童中比高社会地位儿童更不成熟。我们还将评估以下假设：(5)对快速听觉处理至关重要的系统发育缓慢；(6)低社会地位儿童可能比高社会地位儿童更不成熟。我们将检验以下假设：(1)同样的英语作为第二语言的暴露时间导致3-5岁儿童的语言和相关大脑系统比6-8岁儿童更典型；(2)低SES ESL儿童的注意力系统比高SES ESL儿童更不成熟；(3)低SES ESL儿童的英语语言技能熟练程度更低，相关大脑系统更不成熟。在第三个系列的实验中，我们将通过比较3-5岁单语儿童的大脑组织和行为来评估这些系统的相对可修改性，这些儿童在进行8周的专注于语言或注意力技能训练的小组干预之前和之后。我们将测试增加语言和认知输入将导致语义、语法、语音、注意力技能和相关神经系统增加的假设。相关性：由于拟议的研究将提供关于哪些认知和语言技能以及相关的大脑系统最受环境输入改变的证据，这些研究将为典型发展，风险和ESL儿童的教育和干预计划的开发，评估和改进提供具有实际意义的信息。

DESCRIPTION (provided by applicant): Project Summary: Our broad goals are to characterize the identity, developmental timecourse, and relative plasticity (modifiability/vulnerability) of neural systems and subsystems important in language processing and in attentional and sensory skills that are central to language. In children ages 3-17, we will acquire behavioral data, event-related brain potentials (ERPs), and, in the 6-17 year olds, structural and functional magnetic resonance images (fMRI) of the brain to characterize both the timing and the location of neural activity as participants perform tasks designed to manipulate specific aspects of sensory, attentional, and language processing. We will test the hypotheses that (1) systems important in semantic processing mature earlier than those important in grammatical and phonological processing, and that (2) longer developing systems are less mature in lower compared to higher SES children. In view of the central role of auditory attention and rapid auditory processing in language skills, we will also assess the hypotheses that (3) some aspects of the neural mechanisms underlying focused auditory attention are not mature until at least 10 years of age and (4) these systems are less mature in lower than higher SES children. We will also assess the hypotheses that (5) the systems important for rapid auditory processing develop slowly and (6) may be less mature in lower than higher SES children. We will test the hypotheses that (1) the same duration of exposure to English as a second language results in more typical language and related, brain systems at 3-5 years than at 6-8 years, (2) lower SES ESL children have less mature attentional systems than higher SES ESL children, and (3) lower SES ESL children have lower proficiency English language skills, and the related brain systems are less mature. In a third series of experiments we will assess the relative modifiability of these systems by comparing brain organization and behavior of monolingual children aged 3-5 years before and after 8 weeks of a small group intervention focusing on training language or attentional skills. We will test the hypothesis that increased language and cognitive input will lead to increases in semantic, grammatical, phonological, and attentional skills and related neural systems. Relevance: Since the proposed research will provide evidence about which cognitive and language skills and related brain systems are most altered by environmental input, these studies will contribute information of practical significance for the development, evaluation, and refinement of educational and intervention programs for typically developing, at-risk, and ESL children.