Re: [Pcsim-users] noisy DA modulated STDP synapses - how to add OU noise to a neuron?

[Pecevski D. <de...@ig...>]

Robert Ioiart wrote:
> Hello,
>
> I am a newcomer to PCSIM and as exercise I started implementing the 
> simulations from [LegensteinPecevskiMaass2008].
>
> I got stuck when I tried to define the neuron model, let me explain why.
>
> The simulations in [LegensteinPecevskiMaass2008] use LIF neurons with 
> conductance based synapses subjected to short term dynamics and DA 
> modulated STDP.
>
> My first guess was to use the following built-in types:
> DARecvCbLifNeuron - for the neurons
> DAModStdpDynamicCondExpSynapse - for the synapses
>
> The neurons also receive Ornstein-Uhlenbeck noise as conductance 
> input, but I could not find a built-in neuron or synapse model that 
> incorporates all the above mentioned processes AND noise as well.
>
> My best guess at the moment (after studying the c++ class reference 
> and source code) is that in order to have a OU-noisy DARecvCbLifNeuron 
> I have to extend PCSIM by implementing a class that extends both 
> DARecvCbLifNeuron and OUNoiseGenerator and that implements the virtual 
> method conductanceNoiseInput.
> Something like:
>
> class DARecvCbLifOUNoisyNeuron : public DARecvCbLifNeuron, public 
> OUNoiseGenerator
> {
>  
> SIMOBJECT( CbLifNeuron, AdvancePhase::One )
>
> public:
> ...the constructor taking all the parameters...
>
> virtual double conductanceNoiseInput(){
>    OUNoiseGenerator::advance();
>    return OUNoiseGenerator::getValue();
> }
>
> virtual int reset(double dt){
> return (OUNoiseGenerator::reset(dt) || DARecvCbLifNeuron::reset(dt));
> }
>
> virtual int adjust(double dt){
> return (OUNoiseGenerator::adjust(dt) || DARecvCbLifNeuron::adjust(dt));
> }
>
> }//class
>
> Is this the correct aproach? Is there a simpler way to add noise to a 
> neuron?
Hi Robert,

the following code will add the corresponding excitatory and inhibitory 
parts of the
Ornstein-Uhlenbeck Noise in the DARecvCbLifNeuron:

net.mount(OUNoiseSynapse(0.012e-6, 0.003e-6, 2.7e-3, 0.0), neuron_id_array)
net.mount(OUNoiseSynapse(0.057e-6, 0.0066e-6, 10.5e-3,-75e-3), 
neuron_id_array)

The OUNoiseSynapse if attached/mounted to a neuron injects OU noise in 
the neuron.

cheers!
Dejan
>