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Izhi_Neuron Class Reference

#include <izhi_neuron.h>

Inheritance diagram for Izhi_Neuron:

List of all members.

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Detailed Description

A canonical bursting and spiking neuron.

see Izhikevich E. "Simple model of Spiking Neurons"

Model

A canonical neuron model is implemented where the membrane potential of a neuron is given by

, is the membrane resistance, is the current supplied by the synapses, is a non-specific background current and is a Gaussion random variable with zero mean and a given variance noise.

At time ist set to . If exceeds the threshold voltage it is reset to and hold there for the length of the absolute refractory period.

Implementation

The simple Euler method is used for numerical integration.

Public Member Functions

• virtual int updateInternal (void)

  Recalculate exp. Euler constants.
  
  

• virtual void reset (void)

  Reset the leaky I&F neuron.
  
  

• virtual double nextstate (void)

  Calculate the new membrane voltage and check wheter Vm exceeds the threshold V_thresh.
  
  

• virtual int isRefractory (void)

  Returns 1 (0) if the neuron is (not) in its absolute refractory period.
  
  

Public Attributes

• float Cm

  The membrane capacity [range=(0,1); units=F;].
  
  

• float Rm

  The membrane resistance [units=Ohm; range=(0,1e30)].
  
  

• float Vthresh

  If exceeds a spike is emmited. [units=V; range=(-10,100);].
  
  

• float Vresting

  The resting membrane voltage. [units=V; range=(-1,1);].
  
  

• float Vreset

  The voltage to reset to after a spike. [units=V; range=(-1,1);].
  
  

• float Vinit

  The initial condition for at time . [units=V; range=(-1,1);].
  
  

• float Trefract

  The length of the absolute refractory period. [units=sec; range=(0,1);].
  
  

• float Inoise

  The standard deviation of the noise to be added each integration time constant. [range=(0,1); units=A;].
  
  

• float Iinject

  A constant current to be injected into the LIF neuron. [units=A; range=(-1,1);].
  
  

• float a

  A constant (0.02, 01) describing the coupling of variable u to Vm;.
  
  

• float b

  A constant controlling sensitivity og u.
  
  

• float c

  A constant controlling reset of Vm (1000*Vreset).
  
  

• float d

  A constant controlling reset of u.
  
  

Protected Attributes

• double Vm

  The membrane voltage [readonly; units=V;].
  
  

• double Vb

  The membrane voltage in millivolt.
  
  

• double Vint

  The membrane voltage in millivolt.
  
  

• double u

  internal variable
  
  

• double ub

  The internal variable u adapted to millivolt and millisecond.
  
  

• float Isyn

  synaptic input current
  
  

Private Attributes

• int nStepsInRefr

  If positive then this counter tells us how many time steps we are still in the absolute refractory period.
  
  

• double C1

  Internal constants for the exponential Euler integration of Vm.
  
  

• double C2

  Internal constants for the exponential Euler integration of Vm.
  
  

• double I0

  Internal constants for the exponential Euler integration of Vm.
  
  

Friends

• class csimClassInfoDB

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