Fig. 4: Activator-inhibitor reaction diffusion (AIRD) model of local striatal interaction between CINs and DA axons.
From: Acetylcholine waves and dopamine release in the striatum
a Circuit diagram of the reciprocal interaction between CINs and DA axons, as well as between CINs and GINs, and the dynamical variables use to denote the various elements, including the nAChRs. b Proposed inverted-U-shape dependence of nAChR activation on ACh concentration. The 1–10 µM range, indicated in gray, is hypothesized to be the physiological range, wherein an increase in concentration leads to a reduction in activation. c Extended AIRD model where the reciprocal interaction between CINs and GINs is subsumed into the variable u(x,t), and the DA is represented by v(x,t) (Eqs. 4–6). v is governed by an inverted-U dependence on u, and u is governed by an inverted-N dependence on itself.
