SOURCE MEMORY AND HUMAN PREFRONTAL CORTEX

人类记忆的许多方面在功能上和神经解剖学上已经被 分离例如，在情景记忆领域， 会话的内容（项目存储器）可能比 谁做了评论的记忆（源记忆）。来源记忆和项目 记忆在功能上与额叶和大脑皮层相关， 内侧颞叶。然而，直接 这种假设的神经解剖学证据是有限的。该项目将 比较（1）的电生理和神经解剖基底5 单侧脑梗死患者源记忆和项目记忆 前额皮质的损伤试点研究将在年轻和 老年对照受试者检查口语单词的项目记忆， 语音的源存储器。然后，事件相关脑电位（ERP）， 磁共振成像（MRI），并将获得行为数据 来自患有和不患有失语症的额叶患者组，并与 数据来自年龄匹配的对照组。这项研究将提供 关于所观察到的ERP效应的神经基质的信息。我们 以前的研究结果表明，下前额叶皮层和邻近的 失语性中风患者受损的区域（前和前 颞尖）是产生晚期正电位的关键 在词汇判断任务中观察到的。此外，我们还将研究 项目和源记忆过程的时间，通过相关的ERP与 行为表现最近的控制试验数据表明， 源记忆和项目记忆分别与不同的神经系统结合， 时间特征在目前的建议中，我们将研究 左或右前额叶亚区MRI定义的损伤患者 皮层指导性的理论框架是， 源记忆的作用大于项目记忆，而中间记忆在源记忆中的作用大于项目记忆。 颞叶更多地参与项目记忆而不是源记忆。未来 研究将进一步评估这一假设在患者的损害， 内侧颞区包括前丘和内嗅皮质。这 结合ERP，病变和行为方法将研究的贡献 与言语记忆处理的不同方面， 特别是用于上下文存储器（源存储器）和用于内容的存储器 (item内存）。

Many aspects of human memory have been functionally and neuroanatomically dissociated. In the realm of episodic memory, for example, memory for the content of a conversation (item memory) may be more persistent than the memory of who made the comments (source memory). Source memory and item memory have been functionally correlated with the frontal lobes and the medial temporal lobes, respectively. However, the amount of direct neuroanatomical evidence for this hypothesis is limited. This project will compare the electrophysiological and neuroanatomical substrate5 of (1) source memory and (2) item memory in neurological patients with unilateral lesions of prefrontal cortex. Pilot studies will be run in young and elderly control subjects to examine item memory for spoken words and source memory for voice. Then, event-related brain potential (ERP), magnetic resonance imaging (MRI), and behavioral data will be obtained from groups of frontal patients with and without apha5ia and compared to data from age-matched controls. This line of research will provide information on the neural substrates of the observed ERP effects. Our previous results demonstrated that inferior prefrontal cortex and adjacent regions damaged in aphasic stroke patients (the insula and anterior temporal tip) are critical for generating the late positive potentials observed in a lexical decision task. Additionally, we will look at the timing of item and source memory processes by correlating ERPs with behavioral performance. Recent pilot data from controls suggest that source and item memory engage separate neural systems with different temporal characteristics. In the current proposal, we will study groups of patients with MRI-defined damage in subregions of left or right prefrontal cortex. The guiding theoretical framework is that prefrontal cortex plays a greater role in source memory than in item memory, while the medial temporal lobes are more involved in item than source memory. Future research will further evaluate this hypothesis in patients with damage to medial temporal areas including hippocampu5 and entorhinal cortex. This combined ERP, lesion, and behavioral approach will study the contributions of prefrontal cortex to different aspects of verbal memory processing, specifically memory for context (source memory) and memory for content (item memory).