Causes and Consequences of Lexical Activation

描述（申请人提供）：理解语言是人类最基本的认知能力之一。它在人的正常发育中起着重要的作用，是许多领域获取信息的主要手段。许多心理障碍（如精神分裂症）可破坏该系统通常令人印象深刻的功能，大大加剧了这些障碍的负面后果。心理语言学家在阐明语言理解的结构和过程方面取得了重大进展。尽管取得了这些进展，但关于单词在人的“心理词汇库”中是如何表现的，还有很多有待研究。这个领域的关键问题围绕着词汇表示和词汇访问的问题。理论必须说明一个口语单词的呈现是如何导致一个特定的词汇表征被激活的，以及这种激活的影响是什么：一个活跃的词汇表征对其他的词汇表征有什么影响，对其他层次表征的单位有什么影响？

DESCRIPTION (provided by applicant): Understanding language is one of the most fundamental human cognitive abilities. It plays an important role in normal development, and is the major means for acquiring information in many domains. A number of psychological disorders (e.g., schizophrenia) can disrupt the normally impressive functioning of this system, greatly exacerbating the negative consequences of these disorders. Psycholinguists have made significant progress in clarifying the structures and processes that underlie language comprehension. Despite this progress, much remains to be learned about how words are represented in a person's "mental lexicon". Critical remaining issues in this area revolve around questions of lexical representation, and lexical access. Theories must specify how the presentation of a spoken word leads to a particular lexical representation becoming activated, and what the effects of such activation are: What effect does one active lexical representation have on others, and on units at other levels of representation? The current proposal includes a large set of theoretically-driven empirical studies of lexical activation. The empirical investigations are organized into three interlocking groups of experiments. One set of studies examines how phonetic variation can affect lexical access, and can even change the lexical representations themselves. Such variation can have surprisingly powerful effects on how words are represented in the lexicon. A second set of studies examines even more fundamental changes in the lexicon: How do adults add new items to their mental lexicons, and what are the consequences of such changes? The third set of experiments investigates the dynamics of lexical competition: How does the activation of one lexical item affect the activation levels of other lexical entries? The product of the proposed research will be a much better understanding of the architecture of the system that accomplishes language comprehension. These studies will provide a much more detailed picture of how the mental lexicon changes over both the short term, and the longer term. Such an understanding is critical to our understanding language processing. In turn, because language is such a fundamental cognitive ability, progress in describing language processing will enhance our understanding of human cognition, under both normal and disordered conditions.