Subsections
Izhi_Neuron
see Izhikevich E. "Simple model of Spiking Neurons"
A canonical neuron model is implemented where the membrane potential Vm of a neuron is given by
, Rm is the membrane resistance, Isyn(t) is the current supplied by the synapses, Iinject is a non-specific background current and Inoise is a Gaussion random variable with zero mean and a given variance noise.
At time t=0 Vm ist set to Vinit . If Vm exceeds the threshold voltage Vthresh it is reset to Vreset and hold there for the length Trefract of the absolute refractory period.
The simple Euler method is used for numerical integration.
- Cm (F) :
- The membrane capacity Cm
- Rm (Ohm) :
- The membrane resistance Rm
- Vthresh (V) :
- If Vm exceeds Vthresh a spike is emmited.
- Vresting (V) :
- The resting membrane voltage.
- Vreset (V) :
- The voltage to reset Vm to after a spike.
- Vinit (V) :
- The initial condition for Vm at time t=0.
- Trefract (sec) :
- The length of the absolute refractory period.
- Inoise (A) :
- The standard deviation of the noise to be added each integration time constant.
- Iinject (A) :
- A constant current to be injected into the LIF neuron.
- a :
- A constant (0.02, 01) describing the coupling of variable u to Vm;.
- b :
- A constant controlling sensitivity og u.
- c :
- A constant controlling reset of Vm (1000*Vreset).
- d :
- A constant controlling reset of u.
- type :
- Type (e.g. inhibitory or excitatory) of the neuron
- Vm (V) :
- The membrane voltage Vm
- Vb :
- The membrane voltage in millivolt.
- Vint :
- The membrane voltage in millivolt.
- u :
- internal variable
- ub :
- The internal variable u adapted to millivolt and millisecond.
- Isyn :
- synaptic input current
- nIncoming :
- Number of incoming synapses
- nOutgoing :
- Number of outgoing synapses