Fig. 13

Firing threshold manifolds: dynamic vs. static inhibition. Firing threshold manifolds of dynamic inhibition and static inhibition are here plotted together. Recall the firing threshold manifolds for dynamic inhibition are the nonsingular canards, here shown for odd values of ${\tau }_s$ between 1–15 (solid purple). The firing threshold manifold for static inhibition is the stable manifold of ${\mathbf{eq}}_2$ (orange dashed) shown earlier in Fig. 12. For decreasing values of ${\tau }_s$ (darker shades of purple), the nonsingular canards more closely resemble the static inhibition threshold manifold. Note each system (dynamic or static inhibition) used to calculate a threshold manifold required the reduction $\tilde{x}={\tilde{x}}_{\mathrm{\infty }}(v)$, for $x=m,h,n$, to allow calculation along repelling manifolds