Neuroscience Research Institute, Seoul National University College of Medicine, Seoul, South Korea, 03080.
Department of Neurosurgery, Seoul National University Hospital, Seoul, South Korea, 03080.
eNeuro. 2023 Feb 15;10(2). doi: 10.1523/ENEURO.0252-22.2023. Print 2023 Feb.
Hippocampal neuronal activity at a time preceding stimulus onset affects episodic memory performance. We hypothesized that neuronal activity preceding an event supports successful memory formation; therefore, we explored whether a characterized encoding-associated brain activity, viz. the neuronal activity preceding a stimulus, predicts subsequent memory formation. To address this issue, we assessed the activity of single neurons recorded from the hippocampus in humans, while participants performed word memory tasks. Human hippocampal single-unit activity elicited by a fixation cue preceding words increased the firing rates (FRs) and predicted whether the words are recalled in a subsequent memory test; this indicated that successful memory formation in humans can be predicted by a preceding stimulus activity during encoding. However, the predictive effect of preceding stimulus activity did not occur during retrieval. These findings suggest that the preparative arrangement of brain activity before stimulus encoding improves subsequent memory performance.
在刺激出现之前的时间里，海马体神经元的活动会影响情景记忆的表现。我们假设，在事件发生之前的神经元活动支持成功的记忆形成；因此，我们探索了一种特定的与编码相关的大脑活动，即刺激前的神经元活动，是否可以预测随后的记忆形成。为了解决这个问题，我们评估了人类在进行单词记忆任务时从海马体记录的单个神经元的活动。在单词之前的注视提示引起的人类海马体单个神经元活动增加了发放率（FRs），并预测了单词是否会在随后的记忆测试中被回忆起来；这表明，在人类中，成功的记忆形成可以通过编码过程中之前的刺激活动来预测。然而，在检索过程中，之前的刺激活动的预测作用并没有发生。这些发现表明，在刺激编码之前，大脑活动的预备安排可以提高随后的记忆表现。
