Human data collected using noninvasive imaging techniques have established the importance of parietal regions towards episodic memory retrieval, including the angular gyrus and posterior cingulate cortex. Such regions comprise part of a putative core episodic retrieval network. In free recall, comparisons between contextually appropriate and inappropriate recall events (i.e. prior list intrusions) provide the opportunity to study memory retrieval networks supporting veridical recall, and existing findings predict that differences in electrical activity in these brain regions should be identified according to the accuracy of recall. However, prior iEEG stud- ies, utilizing principally subdural grid electrodes, have not fully characterized brain activity in parietal regions during memory retrieval and have not examined connectivity between core recollection areas and the hippocampus or prefrontal cortex. Here, we employed a data set obtained from 100 human patients implanted with stereo EEG electrodes for seizure mapping purposes as they performed a free recall task. This data set allowed us to separately analyze activity in midline versus lateral parietal brain regions, and in anterior versus posterior hippocampus, to identify areas in which retrieval-related activity predicted the recollection of a correct versus an incorrect memory. With the wide coverage afforded by the stereo EEG approach, we were also able to examine interregional connectivity. Our key findings were that differences in gamma band activity in the angular gyrus, precuneus, posterior temporal cortex, and posterior (more than anterior) hippocampus discriminated accurate versus inaccurate recall as well as active retrieval versus memory search. The left angular gyrus exhibited a significant power decrease preceding list intrusions as well as unique phase-amplitude coupling properties, whereas the prefrontal cortex was unique in exhibiting a power increase during list intrusions. Analysis of connectivity revealed significant hemispheric asymmetry, with relatively sparse left-sided functional connections compared to the right hemisphere. One exception to this finding was elevated connectivity between the prefrontal cortex and left angular gyrus. This finding is interpreted as evidence for the engagement of prefrontal cortex in memory monitoring and mnemonic decision-making.

中文翻译：

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直接的大脑记录可识别海马和皮质网络，以区分成功与失败的情景记忆检索

使用非侵入性成像技术收集的人类数据已经确定了顶区域对于阵发性记忆检索的重要性，包括角回和后扣带回皮层。这样的区域包括假定的核心情节检索网络的一部分。在自由召回中，根据上下文适当和不适当的召回事件（即先前的列表入侵）之间的比较提供了研究支持垂直召回的记忆检索网络的机会，并且现有发现预测应根据准确度来识别这些大脑区域的电活动差异召回。但是，以前的iEEG研究主要利用硬膜下格栅电极，在记忆恢复过程中尚未充分表征顶叶区域的大脑活动，也未检查核心记忆区与海马或前额叶皮层之间的连通性。在这里，我们采用了从100名植入立体脑电图电极的人类患者获得的数据集，用于癫痫发作映射，因为他们执行了免费的召回任务。该数据集使我们能够分别分析中线与外侧顶脑区域以及前海马与后海马的活动，以识别与检索相关的活动预测正确记忆与不正确记忆的回忆的区域。在立体脑电图方法提供的广泛覆盖范围内，我们还能够检查区域间的连通性。我们的主要发现是，角回，前胎，后颞叶皮层和海马后部（比前部更多）区分准确召回与不准确召回以及主动检索与记忆检索。左角回在列表入侵之前表现出显着的功率降低，并且具有独特的相位-幅度耦合特性，而前额叶皮层在列表入侵期间表现出功率增加，因此是独特的。连接性分析显示出明显的半球不对称性，与右侧半球相比，左侧功能连接相对稀疏。这一发现的一个例外是前额叶皮层和左角回之间的连通性升高。这一发现被解释为前额叶皮层参与记忆监测和助记符决策的证据。后海马和前海马（比前海马）区分准确召回与不准确召回，以及主动检索与记忆检索。左角回在列表入侵之前表现出显着的功率降低，并且具有独特的相位-幅度耦合特性，而前额叶皮层在列表入侵期间表现出功率增加，因此具有独特性。连接性分析显示出明显的半球不对称性，与右侧半球相比，左侧功能连接相对稀疏。这一发现的一个例外是前额叶皮层和左角回之间的连通性升高。这一发现被解释为前额叶皮层参与记忆监测和助记符决策的证据。后海马和前海马（比前海马）区分准确召回与不准确召回，以及主动检索与记忆检索。左角回在列表入侵之前表现出显着的功率降低，并且具有独特的相位-幅度耦合特性，而前额叶皮层在列表入侵期间表现出功率增加，因此具有独特性。连接性分析显示出明显的半球不对称性，与右侧半球相比，左侧功能连接相对稀疏。这一发现的一个例外是前额叶皮层和左角回之间的连通性升高。这一发现被解释为前额叶皮层参与记忆监测和助记符决策的证据。