//This is the mahon et al 2000 model as implemented by Kevin Biddell
// all questions should be directed to Kevin at kevin.biddell@gmail.com
// 7/7/06
// this experimental paradigm is trying to replicate fig 2A
load_file("nrngui.hoc")
create soma
celsius =37 // the value from mahon et al 2000
access soma
soma{
nseg = 3
diam= 5.6419 // from gruber c_cell this gives SA=100 uM^2
L = 5.6419 // from gruber c_cell this gives SA=100 uM^2
insert Nam
insert Km
insert Leakm
insert Kirm
insert KAfm
insert KAsm
insert Krpm
insert NaPm
insert NaSm
}
// create an electrode in the soma that creates two current pulses (200 ms in duration) 200ms apart
objectvar stim1,stim2
stim1 = new IClamp(0.5)
stim1.del = 100
stim1.dur = 200
stim1.amp = 0.00167 //From Fig2Ab correct only for SA=100 uM
stim2 = new IClamp(0.5)
stim2.del = 500
stim2.dur = 200
stim2.amp = 0.00167 //From Fig2Ab correct only for SA=100 uM
tstop = 800
v_init = -77.4 //11/13/06
// create an "artificial" synaptic input current
//THIS IS USED INSTEAD OF THE SECOND CURRENT INJECTED PULSE
objref Asynm
Asynm = new AlphaSynapse(0.1)
Asynm.onset = 2000 //this is set at 1400 to keep it from going to include make 500
Asynm.tau = 15
Asynm.gmax = 0.0000345 // this is in mhos in the article it is 0.0345 mS
Asynm.e = 0
// the background noise input only use during synaptic input
objref mnoise
mnoise= new NetStim(0.1)
mnoise.interval=7
mnoise.number=6
mnoise.start=2000 //this is set at 1400 to keep it from going, to include make 500
mnoise.noise=1
// creating the input point
objectvar syn
soma syn= new ExpSyn(0) // 15 ms is the decay time
syn.tau=15 // this tau is for each spike of voltage
syn.e=0
// creating the connection between mnoise and syn
objref bridge
mnoise bridge = new NetCon(mnoise,syn,-77.4,0.1,0.000004) //turn up or down change weight (last variable)
// if ths is not satisfactory maybe you could input the noise into the created alpha synapse