Fig. 2.

Period and duty-cycle level sets for the FHN model in the λ–α parameter space. A: period; B: duty cycle. The colored bars code for the values of the corresponding attribute. The red dots refer to point in these maps that are further examined and described (see Level sets in the λ–α parameter space: compensation mechanisms and Fig. 3). We used the canonical parameter values for the v-nullcline (h = 2 and a = 3). Black curves: period level set for T = 100 (A); duty-cycle level set for DC = 0.4 (B); ε = 0.01.