New York University, Center for Neural Science, New York, NY 10003, USA; Graduate Program in Neuroscience and Physiology, New York University Langone Medical Center, New York, NY 10016, USA.
New York University, Center for Neural Science, New York, NY 10003, USA; Neuroscience Institute at the NYU Langone Medical Center, New York, NY 10016, USA; SUNY Downstate, Brooklyn, NY 11203, USA.
Neuron. 2018 May 16;98(4):832-845.e5. doi: 10.1016/j.neuron.2018.04.018. Epub 2018 May 3.
The dentate gyrus (DG) is crucial for behaviorally discriminating similar spatial memories, predicting that DG place cells change ("remap") their relative spatial tuning ("place fields") for memory discrimination. This prediction was never tested, although DG place cells remap across similar environments without memory tasks. We confirm this prior finding but find that DG place fields do not remap across spatial tasks that require DG-dependent memory discrimination. Instead of remapping, place-discriminating discharge is observed transiently among DG place cells, particularly when memory discrimination is most necessary. The DG network may signal memory discrimination by expressing distinctive sub-second network patterns of co-firing at memory discrimination sites. This involves increased coupling of discharge from place cells and interneurons, as was observed during successful, but not failed, behavioral expression of memory discrimination. Instead of remapping, these findings indicate that memory discrimination is signaled by sub-second patterns of correlated discharge within the dentate network.
齿状回（DG）对于行为上区分相似的空间记忆至关重要，这表明 DG 位置细胞会改变（“重映射”）其相对的空间调谐（“位置场”）以进行记忆区分。尽管 DG 位置细胞在没有记忆任务的情况下会在相似的环境中重映射，但这一预测从未得到过验证。我们证实了这一先前的发现，但发现 DG 位置场不会在需要 DG 依赖性记忆区分的空间任务中重映射。相反，在 DG 位置细胞中观察到位置区分放电的短暂出现，特别是在最需要记忆区分时。DG 网络可能通过在记忆区分部位表达独特的亚秒级网络共激活模式来发出记忆区分信号。这涉及到来自位置细胞和中间神经元的放电的耦合增加，正如在成功但不是失败的记忆区分行为表达期间观察到的那样。这些发现表明，记忆区分是由齿状回网络内的亚秒级相关放电模式来发出信号的，而不是重映射。
