Simulations predict that the burst mode dwell time, rather than latency to burst, determines the stimulation-rate dependence of I_sus. The figure illustrates the effect on I_sus of changing the burst mode exit rates (open circles, 10^–6 ms^–1; dashes, 10^–5 ms^–1; filled diamonds, 10^–4 ms^–1) with fixed entry rates. In each panel, computations are shown for fast (interpulse interval, 20 milliseconds, left) and slow (interpulse interval, 1 second, right) stimulation rates (protocol described in Figure 8 legend). I_sus at the end of each depolarization pulse (I_susn) is plotted as a percentage of I_sus at the end of the first pulse (I_sus1). The pulse-dependent reduction of I_sus for each burst mode exit rate is unchanged regardless of the fixed entry rate (10^–4 ms^–1 in a, 10^–5 ms^–1 in b, and 10^-6 ms^–1 in c).