GeNN  3.3.0
GPU enhanced Neuronal Networks (GeNN)
NeuronModels::Izhikevich Class Reference

Izhikevich neuron with fixed parameters [1]. More...

#include <newNeuronModels.h>

Inheritance diagram for NeuronModels::Izhikevich:
NeuronModels::Base NewModels::Base Snippet::Base NeuronModels::IzhikevichVariable

Public Types

typedef Snippet::ValueBase< 4 > ParamValues
 
typedef NewModels::VarInitContainerBase< 2 > VarValues
 
typedef NewModels::VarInitContainerBase< 0 > PreVarValues
 
typedef NewModels::VarInitContainerBase< 0 > PostVarValues
 
- Public Types inherited from Snippet::Base
typedef std::function< double(const std::vector< double > &, double)> DerivedParamFunc
 
typedef std::vector< std::string > StringVec
 
typedef std::vector< std::pair< std::string, std::string > > StringPairVec
 
typedef std::vector< std::pair< std::string, std::pair< std::string, double > > > NameTypeValVec
 
typedef std::vector< std::pair< std::string, DerivedParamFunc > > DerivedParamVec
 

Public Member Functions

virtual std::string getSimCode () const override
 Gets the code that defines the execution of one timestep of integration of the neuron model. More...
 
virtual std::string getThresholdConditionCode () const override
 Gets code which defines the condition for a true spike in the described neuron model. More...
 
virtual StringVec getParamNames () const override
 Gets names of of (independent) model parameters. More...
 
virtual StringPairVec getVars () const override
 Gets names and types (as strings) of model variables. More...
 
- Public Member Functions inherited from NeuronModels::Base
virtual std::string getResetCode () const
 Gets code that defines the reset action taken after a spike occurred. This can be empty. More...
 
virtual std::string getSupportCode () const
 Gets support code to be made available within the neuron kernel/funcion. More...
 
virtual NewModels::Base::StringPairVec getExtraGlobalParams () const
 
virtual NewModels::Base::NameTypeValVec getAdditionalInputVars () const
 
- Public Member Functions inherited from NewModels::Base
size_t getVarIndex (const std::string &varName) const
 Find the index of a named variable. More...
 
- Public Member Functions inherited from Snippet::Base
virtual ~Base ()
 
virtual DerivedParamVec getDerivedParams () const
 

Static Public Member Functions

static const NeuronModels::IzhikevichgetInstance ()
 

Additional Inherited Members

- Static Protected Member Functions inherited from NewModels::Base
static size_t getVarIndex (const std::string &varName, const StringPairVec &vars)
 

Detailed Description

Izhikevich neuron with fixed parameters [1].

It is usually described as

\begin{eqnarray*} \frac{dV}{dt} &=& 0.04 V^2 + 5 V + 140 - U + I, \\ \frac{dU}{dt} &=& a (bV-U), \end{eqnarray*}

I is an external input current and the voltage V is reset to parameter c and U incremented by parameter d, whenever V >= 30 mV. This is paired with a particular integration procedure of two 0.5 ms Euler time steps for the V equation followed by one 1 ms time step of the U equation. Because of its popularity we provide this model in this form here event though due to the details of the usual implementation it is strictly speaking inconsistent with the displayed equations.

Variables are:

  • V - Membrane potential
  • U - Membrane recovery variable

Parameters are:

  • a - time scale of U
  • b - sensitivity of U
  • c - after-spike reset value of V
  • d - after-spike reset value of U

Member Typedef Documentation

◆ ParamValues

◆ PostVarValues

◆ PreVarValues

◆ VarValues

Member Function Documentation

◆ getInstance()

static const NeuronModels::Izhikevich* NeuronModels::Izhikevich::getInstance ( )
inlinestatic

◆ getParamNames()

virtual StringVec NeuronModels::Izhikevich::getParamNames ( ) const
inlineoverridevirtual

Gets names of of (independent) model parameters.

Reimplemented from Snippet::Base.

Reimplemented in NeuronModels::IzhikevichVariable.

◆ getSimCode()

virtual std::string NeuronModels::Izhikevich::getSimCode ( ) const
inlineoverridevirtual

Gets the code that defines the execution of one timestep of integration of the neuron model.

The code will refer to for the value of the variable with name "NN". It needs to refer to the predefined variable "ISYN", i.e. contain , if it is to receive input.

Reimplemented from NeuronModels::Base.

◆ getThresholdConditionCode()

virtual std::string NeuronModels::Izhikevich::getThresholdConditionCode ( ) const
inlineoverridevirtual

Gets code which defines the condition for a true spike in the described neuron model.

This evaluates to a bool (e.g. "V > 20").

Reimplemented from NeuronModels::Base.

◆ getVars()

virtual StringPairVec NeuronModels::Izhikevich::getVars ( ) const
inlineoverridevirtual

Gets names and types (as strings) of model variables.

Reimplemented from NewModels::Base.

Reimplemented in NeuronModels::IzhikevichVariable.


The documentation for this class was generated from the following file: