COMMENT Since this is an electrode current, positive values of i depolarize the cell and in the presence of the extracellular mechanism there will be a change in vext since i is not a transmembrane current but a current injected directly to the inside of the cell. n pulses of amp and dur starting at del with interval del1 between them. ENDCOMMENT NEURON { POINT_PROCESS NIClamp RANGE del, dur, amp, del1, n, i ELECTRODE_CURRENT i } UNITS { (nA) = (nanoamp) } PARAMETER { del = 1(ms) <0,1e9> dur = .1(ms) <0,1e9> amp (nA) del1 = 2(ms) <1e-9,1e9> :time between pulses (off to on) n = 3 <0,1e9> : number of pulses } ASSIGNED { i (nA) tev (ms) cnt on a(nA)} INITIAL { i = 0 cnt = 0 tev = del on = 0 state() } BREAKPOINT { SOLVE state METHOD cvode_t i = a } PROCEDURE state() { if (cnt < n) { if (at_time(tev)) { if (on == 0) { : turn on a = amp on = 1 : printf("cnt=%g a=%g t=%g t-tev=%g\n", cnt+1, a, t, t-tev) tev = tev + dur at_time(tev) : notify system of the new value of tev }else{ : turn off a = 0 on = 0 : printf("cnt=%g a=%g t=%g t-tev=%g\n", cnt+1, a, t, t-tev) tev = tev + del1 at_time(tev) : notify system of the new value of tev cnt = cnt + 1 } } } }