Fig. 4

Number of spikes fired as a function of $G_i$ for $G=100$. The blue points show results from direct numerical simulations of (2), (3) while the red and black points show the predictions from equations. Specifically, the red points are derived from (a) equation (21) with $E=1.2$, $I=0.7$ such that $E+I-2EI>0$ and (b) equation (18) with $E=2$, $I=0.7$ such that $E+I-2EI<0$. The same parameter values were used for the black points but the average $(\delta (g_i)+{\delta }_f)/2$ is replaced by $\delta (g_i)$ in equation (21) in (a) and the average $(\delta (g_0)+\delta (g_i))/2$ is replaced by $\delta (g_0)$ in equation (16) in (b).