N=1201; % total simulation time, ms (+1 to take into account the last bin)
sw=1200; % duration of one sweep
dsw=1200; % change of the sweep
av=round(N/sw); % number of sweeps
dt=0.1; %ms
% model parameters
c=217; i=0; gl=12.8;
el=-55.144; vt=-56.252;
delta=0.77; vreset=-68;
a=35.4; tauw=7.5; b=323;
% parameters for external biexponential intput
Am=100; % pA, optimal for inhibition
taus1=1.5; % ms, rise constant
taus2=10; % ms, decay constant
ts=600; % STIMULUS TIME!
% number of spikes
A(1)=0;
tT=20; % delta bin, ms
bin=20; % initial size of a bin, ms
vspike=0;
Ihold=-90;
sigma=3;
corr=2;
temp=0;
j=0;
k=0;
v(1)=-57;
w(1)=0;
input(1)=Ihold;
% t(1)=0;
% zero initial conditions for external stimuli
in(1)=0;
m(1)=0;
tt(1)=1;
time=0;
% bassin of attraction
vb=importdata('vb-90.mat');
wb=importdata('wb-90.mat');
for i=2:1:round(N/dt)
t(i)=(i-1)*dt;
% additional stimulus
% delta function approximation
if t(i)==ts
stim(i)=1/dt;
else
stim(i)=0;
end;
% generate external stimuli
m(i)=dt/taus1/taus2*(Am*(1-in(i-1))*stim(i)/K(1/taus1,1/taus2)-in(i-1)-(taus1+taus2)*m(i-1)) + m(i-1);
in(i)=m(i)*dt + in(i-1);
% generate the noise and the whole stimulus
temp=temp-dt/corr*temp + sqrt(2*dt/corr)*random('normal',0,1,1,1);
input(i)=Ihold + temp*sigma + in(i);
% no dendrite
v(i)=dt/c*(-gl*(v(i-1)-el)+gl*delta*exp((v(i-1)-vt)/delta)-w(i-1)+input(i)) + v(i-1);
w(i)=dt/tauw*(a*(v(i-1)-el)-w(i-1)) + w(i-1);
if v(i)>vspike
v(i-1)=0; % add sticks to the previous step
v(i)=vreset;
w(i)=w(i) + b;
end
% binning
if t(i)>=bin;
bin=bin + tT;
j=j+1; % come to the next bin
if k == 0
A(j)=time;
else
A(j)=A(j) + time;
end;
tt=0; % reset time after each bin
time=0;
end;
% sweep
if t(i)>=sw;
ts=ts+dsw;
sw=sw + dsw;
j=0; % reset the bin number
k=1; % marker for the first sweep
% v(i)=-57; % reset for init. cond. after each sweep
% w(i)=0;
end;
% if belongs to the bassin of attraction
if inpolygon(v(i),w(i),vb,wb) == 1
tt=tt+1; % time inside of the attraction bassin for one bin
time=tt*dt;
end
end
% normalization
A=A/tT/av;
%save psth100000.mat
% plot(ttt,v,ttt,in/10-85,ttt,(input-in)/10-95)