Our brains create new memories by capturing the ‘who/what’, ‘where’ and ‘when’ of everyday experiences. On a neuronal level, mechanisms facilitating a successful transfer into episodic memory are still unclear. We investigated this by measuring single neuron activity in the human medial temporal lobe during encoding of item-location associations. While previous research has found predictive effects in population activity in human MTL structures, we could attribute such effects to two specialized sub-groups of neurons: concept cells in the hippocampus, amygdala and entorhinal cortex (EC), and a second group of parahippocampal location-selective neurons. In both item- and location-selective populations, firing rates were significantly higher during successfully encoded trials. These findings are in line with theories of hippocampal indexing, since selective index neurons may act as pointers to neocortical representations. Overall, activation of distinct populations of neurons could directly support the connection of the ‘what’ and ‘where’ of episodic memory.

我们的大脑通过捕捉日常经历的“人物/事件”、“地点”和“时间”来创造新的记忆。在神经元水平上，促进情景记忆成功转移的机制仍不清楚。我们通过测量人类内侧颞叶在项目-位置关联编码期间的单个神经元活动来研究这一点。虽然之前的研究已经发现人类 MTL 结构中群体活动的预测效应，但我们可以将这种效应归因于两个专门的神经元亚群：海马体、杏仁核和内嗅皮层 (EC) 中的概念细胞，以及第二组海马旁位置的细胞-选择性神经元。在项目选择性和位置选择性群体中，在成功编码的试验中，放电率显着更高。这些发现与海马索引理论一致，因为选择性索引神经元可能充当新皮质表征的指针。总体而言，不同神经元群的激活可以直接支持情景记忆的“内容”和“地点”的联系。