Fig. 1.

(A) State variable for MS model affected by pacemaker behaviour. (B) Nullclines (green: left branch, $v_{\mathrm{m}}^{-}$; red: right branch, $v_{\mathrm{m}}^{+}$) and phase portrait for MS model affected by pacemaker behaviour. Parameter values are reported in the Table 2 of example 2. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)