NEURAL SUBSTRATES OF MEMORY AND SEMANTIC PROCESSING

本提案的主要目标是进一步深入了解 大脑中负责言语中内隐和外显记忆的区域 领域和词汇语义加工。 该项目将利用一个综合的神经心理学和事件相关的 脑电位（ERP）方法来阐明围绕 重复的位置和持续时间以及语义启动效应， 记忆编码和提取的时间过程，以及 概念记忆存储（即，非模态或模态特异性）。我们 以前的研究表明，左和右下颞- 枕叶区域对于视觉词启动是至关重要的。其他结果 证明了下前额叶皮层和邻近的 区域在词汇语义加工中产生显著的损伤 在词汇判断中， 任务 在目前的提案中，我们将研究患有以下疾病的患者群体： 记忆力或语言能力的缺陷。 这些患者具有 局灶性，MRI证实的（1）前额叶皮层，（2） 颞顶交界处，（3）下颞枕纹外 区域，或（4）海马结构。 两组实验是 建议：（1）对照组和患者的行为和ERP研究将 系统地检查了神经解剖学和神经生理学 内隐记忆和外显记忆的基质;（II）行为和ERP 词汇和图片的语义启动研究将比较词汇和图片的语义启动， 和概念加工的能力。这 该项目将提供丰富的神经解剖学数据， 记忆和语义处理的电生理学基础， 对于更好地理解这些操作是如何 受衰老、精神病和神经退行性疾病影响， 神经性的侮辱 大脑中残存的认知能力的模式 这些患者在未来的应用中非常感兴趣， 制定更好的康复战略。

The primary goal of this proposal is to provide further insight into the brain regions responsible for implicit and explicit memory in the verbal domain and lexical-semantic processing at the level of single words. The project will utilize a combined neuropsychological and event-related brain potential (ERP) approach to illuminate controversies surrounding the location and duration of repetition and semantic priming effects, the time course of memory encoding and retrieval, and the nature of conceptual memory stores (i.e., amodal or modality specific). Our previous studies suggested that both left and right inferior temporal- occipital regions are critical for visual word priming. Other results demonstrated that damage to inferior prefrontal cortex and adjacent regions produces significant impairments in lexical-semantic processing and reductions in the amplitude of ERPs observed in a lexical decision task. In the current proposal, we will study groups of patients with defined deficits in memory or language abilities. These patients have focal, MRI-confirmed lesions in subregions of (1) prefrontal cortex, (2) temporal-parietal junction, (3) inferior temporal-occipital extrastriate regions, or (4) hippocampal formation. Two sets of experiments are proposed: (1) Behavioral and ERP studies in controls and patients will systematically examine the neuroanatomical and neurophysiological substrates of implicit and explicit memory; (II) Behavioral and ERP studies of semantic priming for words and pictures will compare lexical and conceptual processing in patients with and without aphasia. This project will provide a wealth of data on the neuroanatomical and elecrophysiological substrates of memory and semantic processing, which are essential for a greater understanding of how these operations are affected by aging, psychiatric and neurodegenerative diseases, and neurological insults. The pattern of spared cognitive abilities in these patients is of great interest with future applications in the development of improved rehabilitation strategies.