Fig. 4

Bifurcation diagram with respect to z shifts with I. The curve of average x, \(\langle x \rangle\), starts at HB to the left of the frame and terminates at SNIC. Colors correspond to \(I=0.18, 3, 6, 9\), left to right. The trajectories evolve closely around the intersection points of the average curves and the z-nullcline (cyan). \(\bar{x} = -1.1\) and \(s=22\) for all I