Figure 5

Power spectral densities (PSD) of the TPSI given a presynaptic population of 200 stationary Poisson neurons. PSD of the TPSI of a depressing synapse ((i) and (ii)) and a facilitating synapse ((iii) and (iv)), when the firing rate of the presynaptic neurons is 10 Hz ((i) and (iii)) and 100 Hz ((ii) and (iv)), predicted by the first- and second-order MF (blue and red lines respectively) compared microscopic simulations (black line). Each PSD is averaged over 5000 simulations and further smoothed using a moving average. Parameters for the depressing synapse: \(\tau _{D}=0.1\text{ s}\), \(\tau _{F}=0.05\text{ s}\), \(U=U_{0}=0.5\). Parameters for the facilitating synapse: \(\tau _{D}=0.1\text{ s}\), \(\tau _{F}=0.7\text{ s}\), \(U=U_{0}=0.1\). A in the upper panel is binned with bin size 0.005 ms