iaf_cond_exp_sfa_rr

iaf_cond_exp_sfa_rr - Conductance based leaky integrate-and-fire model with spike-frequency adaptation and relative refractory mechanisms

Description

iaf_cond_exp_sfa_rr is an implementation of a spiking neuron using integrate-and-fire dynamics with conductance-based synapses, with additional spike-frequency adaptation and relative refractory mechanisms as described in [2], page 166.

Incoming spike events induce a post-synaptic change of conductance modelled by an exponential function. The exponential function is normalised such that an event of weight 1.0 results in a peak current of 1 nS.

Outgoing spike events induce a change of the adaptation and relative refractory conductances by q_sfa and q_rr, respectively. Otherwise these conductances decay exponentially with time constants tau_sfa and tau_rr, respectively.

References

[1]

Meffin H, Burkitt AN, Grayden DB (2004). An analytical model for the large, fluctuating synaptic conductance state typical of neocortical neurons in vivo. Journal of Computational Neuroscience, 16:159-175. DOI: https://doi.org/10.1023/B:JCNS.0000014108.03012.81

[2]

Dayan P, Abbott LF (2001). Theoretical neuroscience: Computational and mathematical modeling of neural systems. Cambridge, MA: MIT Press. https://pure.mpg.de/pubman/faces/ViewItemOverviewPage.jsp?itemId=item_3006127

See also

aeif_cond_alpha, aeif_cond_exp, iaf_chxk_2008

Parameters

Name	Physical unit	Default value	Description
V_th	mV	-57.0mV	Threshold potential
V_reset	mV	-70.0mV	Reset potential
refr_T	ms	0.5ms	Duration of refractory period
g_L	nS	28.95nS	Leak conductance
C_m	pF	289.5pF	Membrane capacitance
E_exc	mV	0mV	Excitatory reversal potential
E_inh	mV	-75.0mV	Inhibitory reversal potential
E_L	mV	-70.0mV	Leak reversal potential (aka resting potential)
tau_syn_exc	ms	1.5ms	Synaptic time constant of excitatory synapse
tau_syn_inh	ms	10.0ms	Synaptic time constant of inhibitory synapse
q_sfa	nS	14.48nS	Outgoing spike activated quantal spike-frequency adaptation conductance increase
q_rr	nS	3214.0nS	Outgoing spike activated quantal relative refractory conductance increase
tau_sfa	ms	110.0ms	Time constant of spike-frequency adaptation
tau_rr	ms	1.97ms	Time constant of the relative refractory mechanism
E_sfa	mV	-70.0mV	spike-frequency adaptation conductance reversal potential
E_rr	mV	-70.0mV	relative refractory mechanism conductance reversal potential
I_e	pA	0pA	constant external input current

State variables

Name	Physical unit	Default value	Description
V_m	mV	E_L	membrane potential
refr_t	ms	0ms	Refractory period timer
is_refractory	boolean	false
g_sfa	nS	0nS	inputs from the sfa conductance
g_rr	nS	0nS	inputs from the rr conductance

Equations

\[\frac{ dg_{sfa} } { dt }= \frac{ -g_{sfa} } { \tau_{sfa} }\]

\[\frac{ dg_{rr} } { dt }= \frac{ -g_{rr} } { \tau_{rr} }\]

\[\frac{ dV_{m} } { dt }= \frac 1 { C_{m} } \left( { (-I_{L} + I_{e} + I_{stim} - I_{syn,exc} - I_{syn,inh} - I_{sfa} - I_{rr}) } \right)\]

Source code

The model source code can be found in the NESTML models repository here: iaf_cond_exp_sfa_rr.

Characterisation