Word Encoding and Recognition in Schizophrenia

描述(由申请人提供)：拟议研究的目标是 使用功能磁共振成像(FMRI)来验证两个主要假设 关于精神分裂症患者记忆障碍的本质。第一个是 精神分裂症的情节记忆受损与语义功能障碍有关 加工，反映在未能激活左额下回(LIFG) 在单词编码和识别期间。第二个假设是，这个LIFG 功能障碍主要是由于患者的受控加工能力受损 语义信息，而不是退化的语义记忆 知识或自动联想过程。 第一个假设将在实验1和实验2中检验。实验1将 采用宾夕法尼亚大学单词识别测试(PWRT)，这将使我们能够复制 既往正电子发射断层扫描发现情节记忆受损 与单词编码和提取过程中的LIFG功能障碍有关。实验二 将采用浅/深单词编码和识别范例，这将 允许我们测试自生成的组织策略在 精神分裂症患者的语义加工困难及相关生活事件相关功能障碍。 第二个主要假设将在最后两个实验中进行检验。 实验3将采用线索语义语言流畅范式，该范式将 使我们能够调查减少受控加工需求对 语言流畅性和LIFG功能。最后的实验将使用未提示的 口语流畅的设计，将允许逐一试验考试 受控加工与自动加工对LIFG功能的影响 这一系列研究有望揭示受损的基本机制 语义加工与相关情景记忆和LIFG缺陷 精神分裂症。建立这一机制将为未来奠定基础 成像研究，有助于为认知能力的发展提供理论基础 旨在纠正语义加工和词汇记忆的干预措施 精神分裂症患者的缺陷，以改善功能结果。

DESCRIPTION (provided by applicant): The goal of the proposed research is to use functional magnetic resonance imaging (fMRI) to test two primary hypotheses about the nature of memory impairments in schizophrenia. The first is that impaired episodic memory in schizophrenia is related to dysfunctional semantic processing, reflected in failure to activate left inferior frontal gyrus (LIFG) during word encoding and recognition. The second hypothesis is that this LIFG dysfunction is primarily due to patients' impaired controlled processing of semantic information, rather than degradation of their semantic memory knowledge or automatic associative processes. The first hypothesis will be tested in experiments 1 & 2. Experiment one will employ the Penn Word Recognition Test (PWRT) which will allow us to replicate previous Positron Emission Tomography findings that impaired episodic memory is related to LIFG dysfunction during word encoding and retrieval. Experiment 2 will employ a shallow/deep word encoding and recognition paradigm that will permit us to test the role of self-generated organizational strategies in the semantic processing difficulties and related LIFG dysfunction in schizophrenia. The second primary hypothesis will be tested in the final two experiments. Experiment 3 will employ a cued semantic verbal fluency paradigm that will allow us to investigate the effect of reducing controlled processing demands on verbal fluency and LIFG function. The final experiment will use an uncued verbal fluency design that will permit a trial-by-trial examination of the effect of controlled versus automatic processing on LIFG function. This series of studies promises to uncover fundamental mechanisms of impaired semantic processing and related episodic memory and LIFG deficits in schizophrenia. Establishing this mechanism will lay the groundwork for future imaging studies and can help provide a rationale for developing cognitive interventions designed to remediate semantic processing and verbal memory deficits in schizophrenia in order to improve functional outcome.