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arXiv 0906.4549q-bio.NCcond-mat.dis-nn
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可塑性整合-激发神经元网络的平均场理论

Mean-field theory of a plastic network of integrate-and-fire neurons

Chun-Chung Chen, David Jasnow

摘要:

我们考虑一个噪声驱动的集成和火灾神经元网络。网络的发展是神经元活动遵循尖峰时间依赖可塑性规则的结果。我们应用自洽的平均场理论的系统,以获得系统的平均活动水平作为平均突触权重的函数,它预测一个一阶过渡和滞后之间的噪声占主导地位的制度和制度的持久性神经活动。假设神经元的泊松放电统计,平均场环境影响下的突触的可塑性动力学可以映射到突触权重空间中的非对称随机游走的动力学。使用一个主方程的小步骤,我们预测一个狭窄的分布的突触权重的规模与平方根的可塑性率的稳定状态的系统给出合理的生理参数值描述神经传输和可塑性。分布对平均场环境的突触权重的依赖性允许我们自洽地确定平均突触权重。也被认为是在总突触电导和可塑性步长的波动的影响。这样的波动导致平滑的一阶过渡为每个神经元的传入突触的数量少,突触的权重分布的加宽,分别。

英文摘要:

We consider a noise driven network of integrate-and-fire neurons. The network evolves as result of the activities of the neurons following spike-timing-dependent plasticity rules. We apply a self-consistent mean-field theory to the system to obtain the mean activity level for the system as a function of the mean synaptic weight, which predicts a first-order transition and hysteresis between a noise-dominated regime and a regime of persistent neural activity. Assuming Poisson firing statistics for the neurons, the plasticity dynamics of a synapse under the influence of the mean-field environment can be mapped to the dynamics of an asymmetric random walk in synaptic-weight space. Using a master-equation for small steps, we predict a narrow distribution of synaptic weights that scales with the square root of the plasticity rate for the stationary state of the system given plausible physiological parameter values describing neural transmission and plasticity. The dependence of the distribution on the synaptic weight of the mean-field environment allows us to determine the mean synaptic weight self-consistently. The effect of fluctuations in the total synaptic conductance and plasticity step sizes are also considered. Such fluctuations result in a smoothing of the first-order transition for low number of afferent synapses per neuron and a broadening of the synaptic weight distribution, respectively.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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