Werner-Reichardt Centre for Integrative Neuroscience, Otfried-Müller-str. 25, 72076 Tübingen, Germany; Graduate Training Centre of Neuroscience-IMPRS, 72074 Tübingen, Germany.
Werner-Reichardt Centre for Integrative Neuroscience, Otfried-Müller-str. 25, 72076 Tübingen, Germany; Institute of Ophthalmic Research, University of Tübingen, Tübingen, Germany.
Cell Rep. 2018 Apr 3;23(1):32-38. doi: 10.1016/j.celrep.2018.03.031.
Learning critically depends on the ability to rapidly form and store non-overlapping representations of the external world. In line with their postulated role in episodic memory, hippocampal place cells can undergo a rapid reorganization of their firing fields upon contextual manipulations. To explore the mechanisms underlying such global remapping, we juxtacellularly stimulated 42 hippocampal neurons in freely moving mice during spatial exploration. We found that evoking spike trains in silent neurons was sufficient for creating place fields, while in place cells, juxtacellular stimulation induced a rapid remapping of their place fields to the stimulus location. The occurrence of complex spikes was most predictive of place field plasticity. Our data thus indicate that plasticity-inducing stimuli are able to rapidly bias place cell activity, simultaneously suppressing existing place fields. We propose that such competitive place field dynamics could support the orthogonalization of the hippocampal map during global remapping.
学习能力主要依赖于快速形成和存储外部世界非重叠表示的能力。与它们在情景记忆中的假定作用一致，海马体位置细胞可以在上下文操作时迅速重新组织其放电场。为了探索这种全局重映射背后的机制，我们在自由移动的小鼠进行空间探索时，通过细胞外刺激了 42 个海马体神经元。我们发现，在沉默神经元中引发尖峰序列足以产生位置场，而在位置细胞中，细胞外刺激会迅速将其位置场重新映射到刺激位置。复杂尖峰的出现最能预测位置场的可塑性。因此，我们的数据表明，诱导可塑性的刺激能够快速改变位置细胞的活动，同时抑制现有的位置场。我们提出，这种竞争性位置场动力学可以支持在全局重映射期间海马体图谱的正交化。
