Fig. 9.

The Oster et al. (2015) model replicates SK block-induced bursting (A) and explains entry into depolarization block using separation of time scales (B). The steepness of the right stable branch of the nullcline is determined by the reversal potential of Na⁺ at 55 mV. (Same as published parameters for Fig. 4, except: i₁ = 0.6, h_a = 0.72, h_a2 = −45, h_a3 = 14, h_b1 = 1.44, h_b2 = −10, p₁ = 0.9, p₂ = −7, p₃ = 19, g_KDR = 17, g_Na = 150, gpers_Na = 0, g_L = 0.3, e_L = −59, K₁ = 370, and g_CAB = 0.02 in the same units as reported previously.) Also the equation for L-type channel closing should have been multiplied by a factor of 0.05.