Fig. 14

A: Bifurcation diagram of the stable limit cycle of (10) with respect to parameter \(g_{M}\). Stable limit cycles are represented by solid curves, while unstable limit cycles are drawn as dashed curves. The stable limit cycle at \(g_{M}=1.5\) mS/cm² continues as \(g_{M}\) decreases and terminates at \(g_{M}^{*} \approx0.67\) mS/cm² (phase delay limit cycles, top branch of stable limit cycles). The bottom branch of stable limit cycles corresponds to \(1:1\) phase-locking when the I-cell fires consistently before the E-cell (phase advance limit cycles). B: Simulation of (10) with units when \(g_{M}=0.65\) mS/cm². The stable limit cycle is on the bottom branch of the stable limit cycles in the bifurcation diagram in A. The I-cell does \(1:1\) phase-lock to the E-cell. However, I-cell consistently spikes before the E-cell does, not immediately after the E-cell’s spikes. The voltage trace of the I-cell is in blue. The external pulses are in red