Memory, Attention, and Default Mode Processes in Human Posteromedial Cortex

描述（由申请人提供）：人类思维的特点是在处理来自物理环境的信息和处理来自长期记忆的自发产生的信息之间不断相互作用，这些信息以当前关注、未来计划、愿望和回忆的形式出现。这项提议旨在探索这种相互作用是如何通过特定的大脑结构实现的。为此，我们建议研究人类后内侧皮层（PMC）的功能，并确定其与侧顶叶皮层（LPC）和内侧颞叶（MTL）结构的相互作用，这些结构已知是控制注意力和记忆的。PMC是大脑结构的一个重要组成部分，它在执行外部定向注意力任务时表现出活动减少，而在受试者不参与任何外部互动和走神的休息状态时表现出较高的活动。迄今为止，PMC功能在人脑中的神经生理学相关性，包括其解剖学和时间特异性，仍未被探索。我们将通过直接监测和可逆地改变有意识的人类受试者在注意力和记忆的认知任务中的PMC活动来解决这一知识空白，这些受试者被植入颅内电极，作为常规手术前癫痫评估的一部分。提议的工作将是第一个

DESCRIPTION (provided by applicant): Human mind is hallmarked by a continuous interplay between processing information from the physical environment and processing spontaneously generated information from long-term memory in the form of current concerns, future plans, wishes and recollections. This proposal aims to explore how this interplay is made possible by specific brain structures. For this purpose, we propose to study the function of the human posteromedial cortex (PMC) and determine its interaction with lateral parietal cortex (LPC) and medial temporal lobe (MTL) structures known to subserve attention and memory. The PMC is an important part of the brain structures that demonstrate reduced activity during the performance of externally directed attention tasks, while demonstrating higher activity during resting states when subjects are not engaged in any external interactions and when their minds wander. To date, the neurophysiological correlates of PMC function in the human brain, including its anatomical and temporal specificity, remain unexplored. We will address this gap of knowledge by directly monitoring and reversibly altering the activity of the PMC during cognitive tasks of attention and memory in conscious human subjects who are implanted with intracranial electrodes, as part of routine presurgical epilepsy evaluation. The proposed work will be the first to combine direct electrocorticography (ECoG) and electrical brain stimulation (EBS) in the human PMC. The neurophysiological activity of each PMC subregion will be directly recorded with high temporal resolution and individual subject anatomical precision, and will be altered to test the effect of 'transient lesions' in each subregion of the PMC during attention and memory conditions. Our overarching framework is that two PMC subregions, namely the posterior cingulated cortex (PCC) and the retrosplenial cortex (RSC), have non-overlapping roles and selective interactions with the networks of attention and memory, respectively. The resulting progress promises to shed light on the deficits associated with PMC dysfunction, in patients with attention deficit disorders, autism, epilepsy, and dementia.