标题： 星形胶质细胞介导的突触可塑性的高级控制 显示英文标题

标题： Astrocyte-Mediated Higher-Order Control of Synaptic Plasticity

摘要： 高阶拓扑信号的动力学日益被视为复杂系统活动的关键方面。一个典型的例子是突触动力学：突触效能随时间变化，由不同的机制驱动。除了传统的节点驱动的短期可塑性机制外，通过高阶相互作用在所谓的三元突触中，星形胶质细胞调节的作用正日益受到重视。然而，节点驱动机制与高阶机制之间的竞争和相互作用尚未被考虑。在这里，我们引入了一个简单的三元突触高阶模型，考虑了短期可塑性中的星形胶质细胞-突触-神经元相互作用。在该模型中，星形胶质细胞的胶质递质释放和突触前内在促进机制共同调节突触处神经递质释放的概率，推广了之前的短期可塑性模型。我们研究了这种机制在一个最小的循环模式中的影响——三个兴奋性漏电积分-发放神经元的有向环，其中一个神经元接收外部刺激并通过电路传播。由于其强烈的循环性，该电路极易产生自我维持的活动，这可能使其对外部输入不敏感。通过星形胶质细胞调节不同突触之间的高阶相互作用，我们表明高阶调节能够稳健地稳定电路动力学，并扩展支持刺激驱动活动的参数空间。我们的发现表明了一种可能的机制，通过这种机制，星形胶质细胞可以通过高阶结构相互作用重塑有效连接并增强信息处理能力——即使是在最简单的循环电路中。 显示英文摘要

摘要： The dynamics of higher-order topological signals are increasingly recognized as a key aspect of the activity of complex systems. A paradigmatic example are synaptic dynamics: synaptic efficacy changes over time driven by different mechanisms. Beyond traditional node-driven short-term plasticity mechanisms, the role of astrocyte modulation through higher-order interactions, in the so-called tripartite synapse, is increasingly recognized. However, the competition and interplay between node-driven and higher-order mechanisms have yet to be considered. Here, we introduce a simple higher-order model of the tripartite synapse accounting for astrocyte-synapse-neuron interactions in short-term plasticity. In the model, astrocyte gliotransmission and pre-synaptic intrinsic facilitation mechanisms jointly modulate the probability of neurotransmitter release at the synapse, generalizing previous short-term plasticity models. We investigate the implications of such mechanisms in a minimal recurrent motif -- a directed ring of three excitatory leaky integrate-and-fire neurons -- where one neuron receives external stimulation that propagates through the circuit. Due to its strong recurrence, the circuit is highly prone to self-sustained activity, which can make it insensitive to external input. By introducing higher-order interactions among different synapses through astrocyte modulation, we show that higher-order modulation robustly stabilizes circuit dynamics and expands the parameter space that supports stimulus-driven activity. Our findings highlight a plausible mechanism by which astrocytes can reshape effective connectivity and enhance information processing through higher-order structural interactions -- even in the simplest recurrent circuits.