LinearPoissonNeuron.cpp

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#include "LinearPoissonNeuron.h"

#include <cmath>

ThreadSpecificRandomDistribution< NormalDistribution > LinearPoissonNeuron::noise_gen;
ThreadSpecificRandomDistribution< UniformDistribution > LinearPoissonNeuron::spike_gen;

int LinearPoissonNeuron::reset( double dt )
{
    SingleOutputSpikeSender::reset();
    noise_gen.set( NormalDistribution(0.0, 1.0) );
    spike_gen.set( UniformDistribution(0.0,1.0) );
    nStepsInRefr   = -1;        /* we are not refractory at the begining     */
    Twindow = dt;    
    //cerr << "LifNeuron::reset\n\n";
    clearSynapticInput();
    return 0;
}


int LinearPoissonNeuron::advance(AdvanceInfo const & ai)
{
    bool register hasFired = false;
    double spikeT = 0.0;

    if (nStepsInRefr > 0) {
        --nStepsInRefr;
    } else  {
        
        double Itot = Isyn + Iinject;

        if ( Inoise > 0.0 ) {
            Itot += ( noise_gen() * Inoise );
        }
        
        Vm = Itot / ( Gsyn + 1.0/ Rm );

        double Rate = Vm * C;

        if ( spike_gen() < Rate * Twindow ) {
            // Note that the neuron has fired!
            hasFired = true;

            // calculate the spike time ( for exact spike timing )
            spikeT = (ai.dt.in_sec() - Twindow) + Twindow * spike_gen();

            // calc number of steps how long we are refractory and the last time window for exact spike timing 
            nStepsInRefr = int( (Trefract - (ai.dt.in_sec() - spikeT) ) / ai.dt.in_sec() );
            Twindow = ai.dt.in_sec() - (Trefract - (ai.dt.in_sec() - spikeT) - nStepsInRefr * ai.dt.in_sec() );
        } 
        else 
                Twindow = ai.dt.in_sec();
    }

    // clear synaptic input for next time step
    clearSynapticInput();

    // Return proper value
    if( hasFired ) {
        out_port.setSpike( ai, spikeT + ai.t.in_sec() );
        return ADVANCEFLAG_HASSPIKED;
    } else {
        return 0;
    }
}



void LinearPoissonNeuron::clearSynapticInput(void)
{
    Isyn = Gsyn = 0;
}

void LinearPoissonNeuron::currentInput( double i )
{
    Isyn += i;
}


void LinearPoissonNeuron::conductanceInput( double g, double Erev )
{
    Gsyn += g;
    Isyn += (g*Erev);
}
 

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