Subtypes of Schizophrenia: ERPs During Memory Processing

描述(申请人提供)：精神分裂症患者及其亲属存在工作记忆和情景记忆障碍，提示这可能代表精神分裂症的一种“认知表型”。本项目建议使用脑事件相关电位(ERPs)和行为测量来研究精神分裂症患者对单词和面部的工作记忆和识别记忆。事件相关电位的精细时间分辨率将有助于确定与这些记忆测试中的异常相关的特定处理阶段(编码、存储和提取)。在单词序列位置测试中的初步ERP发现表明，精神分裂症患者与短期单词存储相关的左额叶慢波减少，单词识别记忆测试中的异常早在刺激开始后100到200毫秒就很明显。记录文字和面部的事件相关电位将提供有关精神分裂症患者记忆功能异常和大脑偏侧的材料特异性的额外信息。60名未服药的精神分裂症患者、60名服用非典型抗精神病药物的患者和60名健康对照的ERP将在连续的位置测试和识别记忆测试中被记录下来，这些测试包括文字和面部刺激。患者和对照组还将接受标准的注意力神经认知测试(CPT)、学习记忆测试(WMS-R)和问题解决测试(WCST)。未服用药物的患者、服用药物的患者和健康对照组将进行比较，以确定他们在这些测试中的表现和大脑ERP的差异是否与药物状态有关。此外，还将对患者亚组和对照的事件相关电位和行为数据进行比较，以帮助识别和验证具有更同质临床和生物学特征的“认知亚型”。一系列研究已经确定了一组患者，他们在注意力和音调感知的筛查测试中表现与健康成年人一样好，但在言语记忆方面存在选择性缺陷(鉴别器，Dsz)，而第二组患者，在筛查测试中表现不佳，显示出普遍认知缺陷的证据(非鉴别器，NDsz)。该项目旨在通过测试假设的材料特定记忆功能的差异、记忆处理不同阶段的ERP异常、标准神经认知测试的缺陷和症状特征来进一步验证这些亚组。

DESCRIPTION (provided by applicant): Working memory and episodic memory impairments are present in patients with schizophrenia and their relatives, suggesting that it may represent a "cognitive phenotype" of schizophrenia. This project proposes to use brain event-related potentials (ERPs) and behavioral measures to study both working memory and recognition memory for words and faces in patients with schizophrenia. The fine temporal resolution of ERPs will aid in determining the specific stages of processing (encoding, storage and retrieval) associated with abnormalities on these memory tests. Preliminary ERP findings during a word serial position test suggest that a left-frontal slow wave associated with short-term storage of words is reduced in schizophrenia patients, and abnormalities during a word recognition memory test are evident as early as 100 to 200 milliseconds after stimulus onset. Recording ERPs to both words and faces will provide additional information concerning material-specificity of abnormalities of memory function and cerebral laterality in schizophrenia. ERPs of 60 unmedicated schizophrenic patients, 60 patients receiving an atypical antipsychotic, and 60 healthy controls will be recorded during serial position tests and recognition memory tests with word and face stimuli. Patients and controls will also be tested on standard neurocognitive tests of attention (CPT), learning and memory (WMS-R), and problem solving (WCST). Unmedicated patients, medicated patients and healthy controls will be compared to determine whether differences in their performance and brain ERPs on these tests are related to medication status. In addition, ERP and behavioral data for patient subgroups and controls will be compared so as to contribute toward the identification and validation of "cognitive subtypes" with more homogeneous clinical and biological characteristics. A series of studies has identified a subgroup of patients who perform as well as healthy adults on a screening test of attention and tonal perception, but who have a selective deficit in verbal memory (discriminators, Dsz), while a second subgroup of patients, who perform poorly on the screening test, show evidence of a generalized cognitive deficit (non-discriminators, NDsz). The project aims to further validate these subgroups by testing hypothesized differences in their material-specific memory function, ERP abnormalities during different phases of memory processing, deficits on standard neurocognitive tests, and symptom features.