Fig. 3.

Spike-frequency adaptation renders a cell's response to relative input intensity changes largely invariant to baseline input. a–d Maximal change in firing frequency (Δf_max−base) for various baseline currents (I_base; gray scale, as indicated in panel a) and relative current step sizes ((I_step − I_base)/I_base). The four panels show the response of the model with varying degrees of spike-frequency adaptation: none (g_Ca = 0 mS/cm²; a), below the physiological-fit value (g_Ca = 0.2 mS/cm²; b), fit to the underlying physiology (g_Ca = 1 mS/cm²; c), and above the physiological-fit value (g_Ca = 2 mS/cm²; d). The inset in panel d shows response variability (〈σ_Δf〉; see Fig. 2) as a function of g_Ca; in this case, the mean was computed across (I_step − I_base)/I_base