COMMENT //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% // // NOTICE OF COPYRIGHT AND OWNERSHIP OF SOFTWARE // // Copyright 2007, The University Of Pennsylvania // School of Engineering & Applied Science. // All rights reserved. // For research use only; commercial use prohibited. // Distribution without permission of Maciej T. Lazarewicz not permitted. // mlazarew@seas.upenn.edu // //%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% ENDCOMMENT NEURON { POINT_PROCESS fvpre NONSPECIFIC_CURRENT i RANGE gmax, g, i GLOBAL a, b, th, e POINTER vpre } UNITS { (nA) = (nanoamp) (mV) = (millivolt) (uS) = (microsiemens) } PARAMETER { gmax=1e-4 (uS) a=12 (/ms) b=0.1 (/ms) e=-75 (mV) th=0 (mV) } ASSIGNED { vpre (mV) v (mV) i (nA) g (uS)} STATE { s } INITIAL { s = a*F(vpre)/(a*F(vpre)+b) } BREAKPOINT { SOLVE state METHOD cnexp g = gmax * s i = g*(v - e) } DERIVATIVE state { s' = a*F(vpre)*(1-s) - b*s } FUNCTION F (v1 (mV)) { F = 1/(1 + exp(-(v1-th)/2(mV))) }