Estévez-Priego Estefanía, Teller Sara, Granell Clara, Arenas Alex, Soriano Jordi
Departament de Física de la Matèria Condensada, Universitat de Barcelona, Barcelona, Spain.
GOTHAM Lab - Institute for Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, Zaragoza, Spain.
Netw Neurosci. 2020 Dec 1;4(4):1160-1180. doi: 10.1162/netn_a_00156. eCollection 2020.
An elusive phenomenon in network neuroscience is the extent of neuronal activity remodeling upon damage. Here, we investigate the action of gradual synaptic blockade on the effective connectivity in cortical networks in vitro. We use two neuronal cultures configurations-one formed by about 130 neuronal aggregates and another one formed by about 600 individual neurons-and monitor their spontaneous activity upon progressive weakening of excitatory connectivity. We report that the effective connectivity in all cultures exhibits a first phase of transient strengthening followed by a second phase of steady deterioration. We quantify these phases by measuring G, the global efficiency in processing network information. We term the sudden strengthening of G upon network deterioration, which increases by 20-50% depending on culture type. Relying on numerical simulations we reveal the role of , an activity-dependent mechanism for synaptic plasticity, in counteracting the perturbative action, neatly reproducing the observed hyperefficiency. Our results demonstrate the importance of synaptic scaling as resilience mechanism.
网络神经科学中一个难以捉摸的现象是损伤后神经元活动重塑的程度。在这里，我们研究了体外逐渐进行突触阻断对皮质网络有效连接性的作用。我们使用两种神经元培养配置——一种由约130个神经元聚集体形成，另一种由约600个单个神经元形成——并在兴奋性连接性逐渐减弱时监测它们的自发活动。我们报告称，所有培养物中的有效连接性都表现出第一阶段的短暂增强，随后是第二阶段的稳定恶化。我们通过测量G（处理网络信息的全局效率）来量化这些阶段。我们将网络恶化时G的突然增强称为“超效率”，根据培养类型，其增加幅度为20% - 50%。依靠数值模拟，我们揭示了一种依赖活动的突触可塑性机制——“稳态可塑性”在抵消扰动作用方面的作用，精确地再现了观察到的超效率。我们的结果证明了突触缩放作为一种弹性机制的重要性。
