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Synapse not located in a section? Arghhhh

Posted: Sun Jan 21, 2007 6:57 am
by epokh
I builded a pyramidal cell with the cell builder (it's a reduced model of the cat visual cortex layer5).

The public members are:

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public soma, BasalTrunk, basal1, basal2, ApicalTrunk, Apical1, Apical2
public Obliques
public all, Basals
public AMPAinL,NMDAinL,AMPAinR,AMPAinL
public GABAin

objref synlist
objectvar AMPAinL,NMDAinL,AMPAinR,NMDAinR //the synapse objects
objectvar GABAin
The init function is as usual

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proc init() {
  topol()
  subsets()
  geom()
  biophys()
  geom_nseg()
  synlist = new List()
  synapses()
  NMDAinit()
  
  x = y = z = 0 // only change via position
}
The synapses are added in the following way:

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proc synapses() {
//synapse on the left basal dendrite
basal1(1) AMPAinL = new ExpSyn() synlist.append(AMPAinL)
basal1(1) AMPAinL{
tau=2 //decay time is 2ms
e=0 //reverse potential is 0 mV
}


//synapses on the right basal dendrite
basal2(1) AMPAinR = new ExpSyn() synlist.append(AMPAinR)
basal2(1) AMPAinR{
tau=2 //decay time is 2ms
e=0 //reverse potential is 0 mV
}

//a GABA synapse on the soma
soma(1) GABAin=new ExpSyn() synlist.append(GABAin)
soma(1) GABAin{
  tau=10 //decay time is 10ms
  e=-70 //the reverse potential for inhibitory synapses is -70mV

}
}
The problem happen when I try to connect with the NetStim!

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load_file("nrngui.hoc")
xopen("PyrCell5.tem")

// load the template
objectvar pyr
pyr=new PyrCell5()

//a current injection into the soma

objectvar iinject
pyr.soma iinject = new IClamp(.5)
// note: for older versions of neuron, use PulseStim instead of IClamp
iinject.del = 2   //start at 2msecond
iinject.dur = 10	// 10 ms of duration
iinject.amp = 3   //3 nanoampere of current


// a spiking activity into the basals
objectvar inspike,incon
inspike=new NetStim()
inspike {
interval=1
number=100
start=2
noise=0
}

//connect the input to the synapse
// the weight is the peak conductance a low level at the beginning
// like 3 nanosiemes
gmaxAMPA=1e-9
incon=new NetCon(inspike,pyr.AMPAinL,0,0,gmaxAMPA)

access pyr.soma
The console says:
ExpSyn[0] point process not located in a section
I tried also

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incon=new NetCon(inspike,pyr.synlist.obj(0),0,0,gmaxAMPA)
And the same error!
I can't find the problem! I think it's a really stupid error, but spent 1 day trying and trying!

Posted: Tue Jan 23, 2007 7:55 pm
by ted
The best way to learn how to do something new in programming is to first try it on a toy
problem. So make yourself a really simple toy cell class that has just one section and one
synapse, and then try using a NetCon to attach a NetStim to the synapse.