Fig. 1

Responses of system (1) to a current injection of $I_{\mathrm{app}}=20\mu {\text{A/cm}}^2$. The current injection is applied from $t=50$ to $t=53$. Overlaid are the responses corresponding to different values of the maximal conductance $g_{\mathrm{SI}}$ (in mS/cm²) of the slow inward current, namely, $g_{\mathrm{SI}}=0.1$, $g_{\mathrm{SI}}=0.5$ and $g_{\mathrm{SI}}=0.6$, which are examples of responses with no ADP, with ADP and a three-spike burst with ADP, respectively.