University of Mainz Medical Center, Anselm-Franz-von-Bentzel-Weg 3, 55128, Mainz, Germany.
Laboratory for Synaptic Plasticity and Connectivity, RIKEN Center for Brain Science, Wako-shi, Saitama, Japan.
Commun Biol. 2023 Sep 11;6(1):930. doi: 10.1038/s42003-023-05303-1.
Our brains continuously acquire and store memories through synaptic plasticity. However, spontaneous synaptic changes can also occur and pose a challenge for maintaining stable memories. Despite fluctuations in synapse size, recent studies have shown that key population-level synaptic properties remain stable over time. This raises the question of how local synaptic plasticity affects the global population-level synaptic size distribution and whether individual synapses undergoing plasticity escape the stable distribution to encode specific memories. To address this question, we (i) studied spontaneously evolving spines and (ii) induced synaptic potentiation at selected sites while observing the spine distribution pre- and post-stimulation. We designed a stochastic model to describe how the current size of a synapse affects its future size under baseline and stimulation conditions and how these local effects give rise to population-level synaptic shifts. Our study offers insights into how seemingly spontaneous synaptic fluctuations and local plasticity both contribute to population-level synaptic dynamics.
我们的大脑通过突触可塑性不断地获取和存储记忆。然而，自发的突触变化也可能发生，这给维持稳定的记忆带来了挑战。尽管突触大小会发生波动，但最近的研究表明，关键的群体水平突触特性随时间保持稳定。这就提出了一个问题，即局部突触可塑性如何影响全局群体水平突触大小分布，以及经历可塑性的单个突触是否会脱离稳定分布来编码特定的记忆。为了解决这个问题，我们（i）研究了自发进化的棘突，（ii）在观察刺激前后棘突分布的同时，在选定的部位诱导突触增强。我们设计了一个随机模型来描述一个突触的当前大小如何在基线和刺激条件下影响其未来的大小，以及这些局部效应如何导致群体水平的突触转移。我们的研究提供了一些见解，说明看似自发的突触波动和局部可塑性如何共同导致群体水平的突触动力学。
