Quasi-renewal theory for step responses with realistic SAP.

(A–C) Population activity responses (top panels; PSTH from 25,000 repeated simulations in blue, quasi-renewal theory in black) to the step current input as shown in bottom panels (black). The input step size was increased from A to C. The mean first and last interspike interval were 4582 ms and 5042 ms, respectively, in A, 142.10.4 and 2141 ms in B, 93.50.2 and 163.20.5 ms in C. (D) Steady-state activity vs. input current for simulations of 25,000 independent neurons (blue) and quasi-renewal theory (black). The SAP was fixed to [22]. For other model parameters see Models and Methods.