DEVELOPMENT OF CEREBRAL SPECIALIZATIONS

这个应用程序的长期目标是评估角色 感官和语言经验在功能发展中的作用 专门的神经系统。不同的泛函概念 视觉系统和语言系统的组织将是 在正常成年人的研究中进行了测试，以及改变输入对 这些系统的发展将通过研究确定 具有特定性质和性质改变的个体的群体 感觉和/或语言体验的时机。事件相关脑 电位(ERPs)将被记录在多个大脑区域，如 首次接触的单语和双语听力受试者 英语发生在不同的年龄，先天失聪和听力障碍。 首次接触ASL的年龄不同的人， 执行旨在激活感官特定方面的任务 语言功能。 拟议的六个系列实验中的每一个的具体目标 是：i.检验背侧和腹侧加工假设 视觉系统内的视流受到不同的影响 从出生起就被剥夺了听力。二、评估假设 语法信息与人脸在时间上的重合 在ASL中的表达导致更大的左半球表现 聋人和听力正常的本地手语者的脸。三、探索 假设语义和语法信息的处理 在英语中是由不同的神经系统和不同的 关键时期，并进一步区分规则和约束 在语法子系统内。四、探索以下假设： (A)调节ASL和ASL的神经系统存在重叠 英语，(B)类似的子系统可以在每个子系统中识别， 独立于情态和(C)情态约束产生 调节语法加工的神经系统的差异 英语和美国手语。V.探索相似神经的假设 具有相似关键时间段的系统协调处理 英语和美国手语的语音信息。VI.利用掩蔽 对比语言自动加工和控制加工的范式 和非语言材料，并检验自动 功能更容易受到早期体验改变的影响 加工的受控方面。 从长远来看，这些研究应该有助于 开发、提炼和评估的现实意义 聋人和语言障碍者的康复和教育计划 个人。因为这些研究将评估 当改变的体验具有最大的影响时的发展， 结果也将对何时具体的教育产生影响 这些计划将优化听力正常儿童的发育。

The long-term objectives of this application are to assess the roles of sensory and language experience in the development of functionally specialized neural systems. Different conceptions of the functional organization of the visual system and the language system will be tested in studies of normal adults and the effects of altered input on the development of these systems will be determined through the study of groups of individuals with specific alterations in the nature and timing of sensory and/or language experience. Event-related brain potentials (ERPs) will be recorded from over several brain regions as monolingual and bilingual hearing subjects whose first exposure to English occurred at different ages, and congenitally deaf and hearing individuals whose first exposure to ASL occurred at different ages, perform tasks designed to activate specific aspects of sensory and language functions. The specific aims of each of the six series of proposed experiments are: I. To test the hypothesis that the dorsal and ventral processing streams within the visual system are differentially affected by auditory deprivation since birth. II. To assess the hypothesis that the temporal coincidence between grammatical information and facial expression in ASL results in greater left hemisphere representation of faces in deaf and hearing native signers. III. To explore the hypothesis that the processing of semantic and grammatical information in English is mediated by different neural systems with different critical periods and to further differentiate rules and constraints within the grammatical subsystem. IV. To explore the hypothesis that (a) there is overlap in the neural systems that mediate ASL and English, (b) similar subsystems can be identified within each that are independent of modality and (c) modality constraints produce differences in the neural systems that mediate grammatical processing in English and ASL. V. To explore the hypothesis that similar neural systems with similar critical periods mediate the processing of phonological information in English and ASL. VI. To utilize masking paradigms to contrast automatic and controlled processing of language and non-language material and to test the hypothesis that automatic functions are more vulnerable to altered early experience than are controlled aspects of processing. In the long run these studies should contribute information of practical significance for developing, refining and evaluating rehabilitative and educational programs for deaf and language impaired individuals. Since these studies will evaluate the periods in development when altered experience has its greatest impact, the results will also have implications for when specific educational programs would optimize development in normal hearing children.