PET ACTIVATION STUDIES OF WORDS

本研究的主要目的是利用现代 在正常受试者中进行功能神经成像以表征大脑 与语言处理的特定方面有关的领域。 这 目前的建议将重点从整个语言缩小到 在三个方面进行单字水平的实验： 1)旨在确定大脑区域参与规则的实验- 基于与基于联想记忆的语言处理。 许多最近 认知心理学的研究集中在区分 在语言过程之间， 基于规则的机制，以及那些基于存储的 协会. 许多研究，包括我们自己的一些工作， 这表明这些不同类型的过程涉及不同的 大脑区域。 提出了解决以下问题的实验： 这种分离的普遍性和使用的程度 不同类型的过程可以通过实验进行操作。 2)旨在探索大脑区域语音的实验 流程. 病变行为和功能成像研究 提出了特定大脑区域之间的特定联系 和不同的语音过程（包括声学， 发音和单词发音过程）。 目前约有 研究之间有趣的重叠，以及一些有趣的 分离 建议的研究将使我们能够进一步 探索不同的参与过程的性质 语音任务，并解决所扮演的不同角色， 颞叶和额叶 3)探索与语义过程相关的特定领域。 一些研究表明，左中颞叶和 额叶区域可以被包括一些形式的任务激活， 语义分析（semantic analysis） 拟议的实验 在以前研究的基础上，通过研究诸如 作为输入的形式，语义信息主体的类型 以及这些信息是如何被访问的 大脑区域的激活。 虽然这项建议的重点是语言过程正常 从这些研究中获得的知识应该是相关的 一系列的健康问题。 例如语言 损伤是中风最悲惨的后果之一， 影像学研究，因为这些可以提供相关的信息， 理解行为缺陷 同样，更深层次的 了解正常功能应提供更有针对性的 未来的康复策略。 从最广泛的意义上说， 正常语言功能的研究，使用所有可用的途径， 包括功能性神经成像，应该会导致更深层次的 有关问题的认识，并采取更好的办法 他们的解决方案。

The major goal of the proposed research is to employ modern functional neuroimaging in normal subjects to characterize brain areas related to specific aspects of language processing. This current proposal narrows the focus from language as a whole to experiments at the level of single words in three areas: 1) experiments designed to identify brain regions involved in rule- based vs. associative memory based language processes. Many recent cognitive psychological studies have focused upon the distinction between language processes which produce transformations using rule-based mechanisms, and those which are based upon stored associations. Many studies, including some of our own work, suggest these different types of processes involve distinct sets of brain regions. Experiments are proposed which address the generality of this dissociation and the extent to which the use of the different types of processes can be experimentally manipulated. 2) experiments designed to explore brain regions to phonological processes. Both lesion-behavior and functional imaging studies have suggested specific correlations between specific brain regions and different phonological processes (including acoustic, articulatory, and word-sound processes). There are currently some intriguing overlaps between studies, as well as some interesting dissociations. The proposed studies will allow us to further explore the nature of the processes involved in different phonological tasks, and to address the different roles played by temporal and frontal regions. 3) to explore specific areas related to semantic processes. Several studies have suggested both left middle temporal and frontal regions may be activated by tasks which include some form of semantic (word meaning) analysis. The proposed experiments build upon previous studies by examining the effect of factors such as the modality of input, the type of semantic information subjects are required to analyze, and how that information is accessed on the activation of brain regions. While this proposal focuses on language processes in normal subjects, the knowledge gained from such studies should be relevant across a wide range of health issues. For example, language impairment is one of the most tragic consequences of stroke, and imaging studies as these may provide information relevant to understanding behavioral deficits. Likewise, a deeper understanding of normal function should provide more targeted rehabilitative strategies in the future. In the broadest sense, studies of normal language function, using all avenues available to us, including functional neuroimaging, should lead to a deeper understanding of the related problems, and to better approaches to their solution.