DEVELOPMENT OF LINGUISTIC COMPETENCE: FMRI STUDIES

许多在围产期中风的儿童发育正常或接近正常的语言能力。因此，这些儿童可以作为使用功能磁共振成像（fMRI）研究发育可塑性的良好模型系统。该探索性项目旨在为围产期中风儿童的广泛和长期的基于功能磁共振成像的调查开发一个基础。目的1：探讨在正常儿童中使用现有功能磁共振成像方法的可行性和有效性。大脑活动表征的方法已经发展了好几年，用于正常和异常的成人人群。虽然其中一些方法可以直接应用于儿童，但其他方法则不那么明显地普遍化。Aim1的研究将评估和开发正常儿童和围产期中风儿童的功能磁共振成像研究方法。目标2：开始研究正常儿童的行为特征和相关的大脑激活模式，使用先前描述的语言任务。任务和功能磁共振成像协议，类似于以前在成人研究中使用的处理单个单词的方法，将被测试和修改。最初，研究对象是7-10岁的儿童。这些实验还将扩展到一小群3-6岁的儿童，以确定与研究这个更小的年龄组有关的问题。目的3：探讨使用目的2中开发的语言任务来研究围产期损伤与行为特征和大脑激活模式的关系的可行性。在Aim 2中成功实施的研究将在7-10岁的儿童中进行，这些儿童尽管在围产期经历了局灶性单侧中风，但没有表现出明显的认知或语言后遗症。目标4：开始开发新的任务集，更广泛地解决语言方面的问题。在许多功能性神经成像实验中，包括我们的实验，使用的任务都倾向于关注单个单词的语音和语义。对单字的初步研究。句法过程的初步研究，包括语法形态和句法理解，将在正常成人和正常儿童中开始。

Many children who have had strokes in the perinatal period develop normal or near-normal linguistic abilities. Consequently, these children should serve as an excellent model system for studying developmental plasticity using functional MRI (fMRI). This exploratory project is designed to develop a substrate for an extensive and long-term fMRI-based investigation of children with perinatal stroke. The following specific aims are proposed: Aim 1: To explore the feasibility and validity of using current fMRI methodologies in normal children. Methods for the characterization of brain activity have been developed over several years for use in normal and abnormal adult populations. Whereas some of these methods might be straightforwardly applied to children, others are less obviously generalizable. Studies in Aim1 will assess and develop methodologies for fMRI studies in normal children and children with perinatal stroke. Aim 2: To begin studies, in normal children, of behavioral profiles and associated brain activation patterns using previously characterized language tasks. Tasks and fMRI protocols, similar to those previously employed in adult studies of the processing of single words, will be tested and modified. Initially, children ages 7-10 will be studied. These experiments will also be extended to a small group of children ages 3-6 to identify problems specifically associated with studying this younger age group. Aim 3: To explore the feasibility of using language tasks developed in Aim 2 for the study o f the relationship of perinatal lesion to behavioral profiles and patterns of brain activation. Studies successfully implemented in Aim 2 will then be performed on children ages 7-10 who, despite enduring a focal unilateral stroke in the perinatal period, do not manifest significant cognitive or linguistic sequelae. Aim 4: To begin development of new sets of tasks that address aspects of language more broadly. The tasks that have been used in many functional neuroimaging experiments, including ours, have tended to focus on the phonology and semantics of single words. Preliminary studies of single words. Preliminary studies of syntactic processes, including grammatical morphology and syntactic comprehension, will be initiated in normal adults and normal children.