that produces bursts dependent on two additional variables analog to the implementation of dynamical synapses: see Kaske&Bertschinger "Traveling wave patterns..."


A nonstandard leaky-integrate-and-fire neuron model is implemented where the membrane potential Vm of a neuron is given by

\begin{displaymath}\tau_m \frac{d V_m}{dt} = -(V_m-V_{resting}) + R_m \cdot (I_{syn}(t)+I_{inject}+I_{noise}) \end{displaymath}

where $\tau_m=C_m\cdot R_m$ is the membrane time constant, 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. Vreset is modulated by u and r to produce spiking dependent on the previous spike pattern At time t=0 Vm ist set toVinit . If Vm exceeds the threshold voltageVthresh it is reset to Vreset and hold there for the length Trefract of the absolute refractory period.


The exponential Euler method is used for numerical integration.

Read/writable Fields

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 default voltage to reset Vm to after a spike.
VBthresh (V) :
spike pattern dependent treshold 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.
uB :
internal parameter uB - recovery from spike facilitation with time constant FB
rB :
internal parameter rB - recovery from spike depression with time constant DB
FB :
FB time constant for recovery from facilitation of spike generation.
DB :
DB time constant for recovery from depression of spike generation.
UB :
UB constant for onset of facilitation of spike generation.
type :
Type (e.g. inhibitory or excitatory) of the neuron

Readonly Fields

Vm (V) :
The membrane voltage Vm
Isyn :
synaptic input current
nIncoming :
Number of incoming synapses
nOutgoing :
Number of outgoing synapses

(C) 2003, Thomas Natschläger last modified 07/10/2006