Figure 2. Spike timing precision with GABA_A or GABA_B inhibition.

In (A–G), the failure probability is P _failure = 0.5. (A): Spike rasterplot for GABA_A coupling. The peak GABA_A conductance is g_a = 1 nS. The frequency of the network oscillation is F ∼20 Hz. (B) Spike rasterplot for GABA_B coupling (g_b = 0.1 nS, F ∼10 Hz). (C,D) Temporal evolution of the spike time jitter σ(n), where n is the index of the oscillatory cycle. Convergence is reached in about 3 cycles, i.e., 300 ms with GABA_B and 150 ms with GABA_A. The initial condition is the desynchronized state (see Methods). (E,F) Same conventions as in (C–D), except that the initial condition is now the synchronized state. (G) Spike time jitter σ obtained at convergence (σ(n) averaged over the last two oscillatory cycles) as a function of the mean inhibitory drive 〈k〉 received by the neurons (the number of neurons N scales from 50 to 400). (H) σ as a function of the failure probability P _failure. In (C–H), the stars represent the spike time jitter estimated from simulations (see Methods, means and standard deviations estimated over 10 runs). The solid curves are for theoretical values obtained from Equation 1 (in C–F) or from Equation 2 (in G–H).