: $Id: MyExp2SynNMDABB.mod,v 1.4 2010/12/13 21:28:02 samn Exp $ NEURON { : THREADSAFE POINT_PROCESS MyExp2SynNMDABB RANGE tau1, tau2, e, i, iNMDA, s, sNMDA, r, tau1NMDA, tau2NMDA, Vwt, smax, sNMDAmax NONSPECIFIC_CURRENT i, iNMDA } UNITS { (nA) = (nanoamp) (mV) = (millivolt) (uS) = (microsiemens) } PARAMETER { tau1 = 0.1 (ms) <1e-9,1e9> tau2 = 10 (ms) <1e-9,1e9> tau1NMDA = 15 (ms) tau2NMDA = 150 (ms) e = 0 (mV) mg = 1 r = 1 smax = 1e9 (1) sNMDAmax = 1e9 (1) Vwt = 0 : weight for inputs coming in from vector } ASSIGNED { v (mV) i (nA) iNMDA (nA) s (1) sNMDA (1) mgblock (1) factor (1) factor2 (1) etime (ms) } STATE { A (1) B (1) A2 (1) B2 (1) } INITIAL { LOCAL tp Vwt = 0 : testing if (tau1/tau2 > .9999) { tau1 = .9999*tau2 } A = 0 B = 0 tp = (tau1*tau2)/(tau2 - tau1) * log(tau2/tau1) factor = -exp(-tp/tau1) + exp(-tp/tau2) factor = 1/factor if (tau1NMDA/tau2NMDA > .9999) { tau1NMDA = .9999*tau2NMDA } A2 = 0 B2 = 0 tp = (tau1NMDA*tau2NMDA)/(tau2NMDA - tau1NMDA) * log(tau2NMDA/tau1NMDA) factor2 = -exp(-tp/tau1NMDA) + exp(-tp/tau2NMDA) factor2 = 1/factor2 } BREAKPOINT { SOLVE state METHOD cnexp : Jahr Stevens 1990 J. Neurosci mgblock = 1.0 / (1.0 + 0.28 * exp(-0.062(/mV) * v) ) s = B - A sNMDA = B2 - A2 if (s >smax) {s =smax }: saturation if (sNMDA>sNMDAmax) {sNMDA=sNMDAmax}: saturation i = s * (v - e) iNMDA = sNMDA * (v - e) * mgblock } DERIVATIVE state { A' = -A/tau1 B' = -B/tau2 A2' = -A2/tau1NMDA B2' = -B2/tau2NMDA } NET_RECEIVE(w (uS)) {LOCAL ww ww=w :printf("NMDA Spike: %g\n", t) if(r>=0){ : if r>=0, g = AMPA + NMDA*r A = A + factor *ww B = B + factor *ww A2 = A2 + factor2*ww*r B2 = B2 + factor2*ww*r }else{ if(r>-1000){ : if r>-1, g = NMDA*r A2 = A2 - factor2*ww*r B2 = B2 - factor2*ww*r } : if r<0 and r<>-1, g = 0 } }