Wu Yujie, Maass Wolfgang
Department of Computing, The Hong Kong Polytechnic University, Hong Kong, SAR, China.
Institute of Theoretical Computer Science, Graz University of Technology, Graz, Austria.
Nat Commun. 2025 Jan 2;16(1):342. doi: 10.1038/s41467-024-55563-6.
Recent experimental studies in the awake brain have identified a rule for synaptic plasticity that is instrumental for the instantaneous creation of memory traces in area CA1 of the mammalian brain: Behavioral Time scale Synaptic Plasticity. This one-shot learning rule differs in five essential aspects from previously considered plasticity mechanisms. We introduce a transparent model for the core function of this learning rule and establish a theory that enables a principled understanding of the system of memory traces that it creates. Theoretical predictions and numerical simulations show that our model is able to create a functionally powerful content-addressable memory without the need for high-resolution synaptic weights. Furthermore, it reproduces the repulsion effect of human memory, whereby traces for similar memory items are pulled apart to enable differential downstream processing. Altogether, our results create a link between synaptic plasticity in area CA1 of the hippocampus and its network function. They also provide a promising approach for implementing content-addressable memory with on-chip learning capability in highly energy-efficient crossbar arrays of memristors.
近期对清醒大脑的实验研究确定了一种突触可塑性规则,该规则有助于在哺乳动物大脑的CA1区域瞬间创建记忆痕迹:行为时间尺度突触可塑性。这种一次性学习规则在五个基本方面与先前考虑的可塑性机制不同。我们为该学习规则的核心功能引入了一个透明模型,并建立了一种理论,能够对其创建的记忆痕迹系统进行有原则的理解。理论预测和数值模拟表明,我们的模型能够创建一个功能强大的内容可寻址存储器,而无需高分辨率的突触权重。此外,它再现了人类记忆的排斥效应,即相似记忆项目的痕迹被拉开,以便进行差异化的下游处理。总之,我们的结果在海马体CA1区域的突触可塑性与其网络功能之间建立了联系。它们还为在具有高能效的忆阻器交叉阵列中实现具有片上学习能力的内容可寻址存储器提供了一种有前景的方法。