Mikkelsen Kaare, Imparato Alberto, Torcini Alessandro
Department of Physics and Astronomy, University of Aarhus, Ny Munkegade, Building 1520, DK-8000 Aarhus C, Denmark.
Department of Physics and Astronomy, University of Aarhus, Ny Munkegade, Building 1520, DK-8000 Aarhus C, Denmark and CNR-Consiglio Nazionale delle Ricerche-Istituto dei Sistemi Complessi, via Madonna del Piano 10, I-50019 Sesto Fiorentino, Italy and INFN Sez. Firenze, via Sansone 1, I-50019 Sesto Fiorentino, Italy.
Phys Rev E Stat Nonlin Soft Matter Phys. 2014 Jun;89(6):062701. doi: 10.1103/PhysRevE.89.062701. Epub 2014 Jun 2.
The collective dynamics of excitatory pulse-coupled neural networks with spike-timing-dependent plasticity (STDP) is studied. Depending on the model parameters stationary states characterized by high or low synchronization can be observed. In particular, at the transition between these two regimes, persistent irregular low frequency oscillations between strongly and weakly synchronized states are observable, which can be identified as infraslow oscillations with frequencies ≃0.02-0.03 Hz. Their emergence can be explained in terms of the Sisyphus effect, a mechanism caused by a continuous feedback between the evolution of the coherent population activity and of the average synaptic weight. Due to this effect, the synaptic weights have oscillating equilibrium values, which prevents the neuronal population from relaxing into a stationary macroscopic state.
研究了具有脉冲时间依赖可塑性（STDP）的兴奋性脉冲耦合神经网络的集体动力学。根据模型参数，可以观察到以高同步或低同步为特征的稳态。特别是，在这两种状态之间的转变处，可以观察到强同步和弱同步状态之间持续的不规则低频振荡，其可被识别为频率约为0.02 - 0.03Hz的超慢振荡。它们的出现可以用西西弗斯效应来解释，这是一种由相干群体活动的演化与平均突触权重之间的连续反馈引起的机制。由于这种效应，突触权重具有振荡平衡值，这阻止了神经元群体松弛到静止的宏观状态。
