LIF.cpp

/**********************************************************************
** This program is part of 'MOOSE', the
** Messaging Object Oriented Simulation Environment.
**           Copyright (C) 2003-2007 Upinder S. Bhalla. and NCBS
** It is made available under the terms of the
** GNU Lesser General Public License version 2.1
** See the file COPYING.LIB for the full notice.
**********************************************************************/

#include "../basecode/header.h"
#include "../basecode/ElementValueFinfo.h"
#include "../biophysics/CompartmentBase.h"
#include "../biophysics/Compartment.h"
#include "IntFireBase.h"
#include "LIF.h"

using namespace moose;

const Cinfo* LIF::initCinfo()
{
    static string doc[] =
    {
        "Name", "LIF",
        "Author", "Upi Bhalla",
        "Description", "Leaky Integrate-and-Fire neuron"
    };
    static Dinfo< LIF > dinfo;
    static Cinfo lifCinfo(
        "LIF",
        IntFireBase::initCinfo(),
        0, 0,
        &dinfo,
        doc,
        sizeof(doc)/sizeof(string)
    );

    return &lifCinfo;
}

static const Cinfo* lifCinfo = LIF::initCinfo();

//////////////////////////////////////////////////////////////////
// Here we put the Compartment class functions.
//////////////////////////////////////////////////////////////////

LIF::LIF()
{
    ;
}

LIF::~LIF()
{
    ;
}

//////////////////////////////////////////////////////////////////
// LIF::Dest function definitions.
//////////////////////////////////////////////////////////////////

void LIF::vProcess( const Eref& e, ProcPtr p )
{
    fired_ = false;
    if ( p->currTime < lastEvent_ + refractT_ )
    {
        Vm_ = vReset_;
        A_ = 0.0;
        B_ = 1.0 / Rm_;
        sumInject_ = 0.0;
        VmOut()->send( e, Vm_ );
    }
    else
    {
        // activation can be a continous variable (graded synapse).
        // So integrate it at every time step, thus *dt.
        // For a delta-fn synapse, SynHandler-s divide by dt and send activation.
        // See: http://www.genesis-sim.org/GENESIS/Hyperdoc/Manual-26.html#synchan
        //          for this continuous definition of activation.
        Vm_ += activation_ * p->dt;
        activation_ = 0.0;
        if ( Vm_ > threshold_ )
        {
            Vm_ = vReset_;
            lastEvent_ = p->currTime;
            fired_ = true;
            spikeOut()->send( e, p->currTime );
            VmOut()->send( e, Vm_ );
        }
        else
        {
            Compartment::vProcess( e, p );
        }
    }
}

void LIF::vReinit(  const Eref& e, ProcPtr p )
{
    activation_ = 0.0;
    fired_ = false;
    lastEvent_ = -refractT_; // Allow it to fire right away.
    Compartment::vReinit( e, p );
}