load_file("nrngui.hoc") /* axon morphology */ create axon[6], mfb[5], filext[20] forall { Ra = 100 cm = 1 insert pas g_pas = 0.00001667 /* 0.00001667 */ e_pas = -80 } access axon[0] for i = 0, 5 axon[i] { nseg = 150 diam = 0.4 L = 150 } for i = 0, 4 mfb[i] { nseg = 7 diam = 7 L = 7 } for i = 0, 4 { connect mfb[i](0), axon[i](1) connect axon[i+1](0), mfb[i](1) } for i = 0, 19 filext[i] { nseg = 20 diam = 0.1 L = 20 } j = 0 for i = 0, 4 { j = 4*i connect filext[j](0), mfb[i](0.4) connect filext[j+1](0), mfb[i](0.6) connect filext[j+2](0), mfb[i](0.4) connect filext[j+3](0), mfb[i](0.6) } /* gNa */ forall insert GNa forall vthreshold_GNa = -57 forall ena = 55 forsec "mfb" gnabar_GNa = 0.0447946 /* S/cm^2 */ forsec "filext" gnabar_GNa = 0.0447946 /* S/cm^2 */ forsec "axon" gnabar_GNa = 0.0447946 /* S/cm^2 */ /* gK */ forall insert GK forall vthreshold_GK = -57 forall ek = -100 forsec "mfb" gkbar_GK = 0.00804191 /* S/cm^2*/ forsec "filext" gkbar_GK = 0.00804191 /* S/cm^2*/ forsec "axon" gkbar_GK = 0.00804191 /* S/cm^2*/ /* gCa */ forsec "mfb" insert GCa forsec "mfb" vthreshold_GCa = -57 forsec "mfb" eca = 75 forsec "mfb" gcabar_GCa = 0.0032 /* S/cm^2*/ forsec "filext" insert GCa forsec "filext" vthreshold_GCa = -57 forsec "filext" eca = 75 forsec "filext" gcabar_GCa = 0.0032 /* S/cm^2*/ /* current pulse at proximal axon */ objectvar stim axon[0] stim = new IClamp(0.02) stim.del = 0.5 stim.dur = 0.1 stim.amp = 0.2 /* init and run parameters */ v_init = -80 dt = 0.002 steps_per_ms = 500 tstop = 3