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Fig. 2 | Biology Direct

Fig. 2

From: Onset, timing, and exposure therapy of stress disorders: mechanistic insight from a mathematical model of oscillating neuroendocrine dynamics

Fig. 2

Nonlinear g c (c) and bistability of fast variables. a The stable states of the decoupled system in Eq. 22 can be visualized as the intersection of the two functions q g c (c) (dashed curve) and q 2 c (gray line). For a given Hill-type function g c (c), Eq. 22 can admit one or two stable states (solid circles), depending on function parameters. The unstable steady state is indicated by the open circle. b Bifurcation diagram of the decoupled system (Eq. 22) with q as the bifurcation parameter. Solid and dashed segments represent stable and unstable steady states of the fast variables, respectively. L and U label basins of attraction associated with the lower and upper stable branches of the c-nullcline. Left and right bifurcation points (q L,c L) and (q R,c R) are indicated. Fixed points of c appear and disappear through saddle node bifurcations as q is varied between q L and q R

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