aeif_psc_alpha – Current-based exponential integrate-and-fire neuron model

Description

aeif_psc_alpha is the adaptive exponential integrate and fire neuron according to Brette and Gerstner (2005). Synaptic currents are modelled as alpha-functions.

This implementation uses the embedded 4th order Runge-Kutta-Fehlberg solver with adaptive step size to integrate the differential equation.

The membrane potential is given by the following differential equation:

\[C dV/dt= -g_L(V-E_L)+g_L\cdot\Delta_T\cdot\exp((V-V_T)/\Delta_T) - w(t) + I_syn(t) + I_e\]

and

\[\tau_w \cdot dw/dt= a(V-E_L) - w\]
\[I_{syn}(t) ~ \sum_k (t-t^k) \exp((t-t^k)/\tau_{syn})H(t - t^k) .\]

Here \(H(t)\) is the Heaviside step function and k indexes incoming spikes.

For implementation details see the aeif_models_implementation notebook.

See also [1].

Parameters

The following parameters can be set in the status dictionary.

Dynamic state variables:

V_m

mV

Membrane potential

I_ex

pA

Excitatory synaptic current

dI_ex

pA/ms

First derivative of I_ex

I_in

pA

Inhibitory synaptic current

dI_in

pA/ms

First derivative of I_in

w

pA

Spike-adaptation current

g

pA

Spike-adaptation current

Membrane Parameters

C_m

pF

Capacity of the membrane

t_ref

ms

Duration of refractory period

V_reset

mV

Reset value for V_m after a spike

E_L

mV

Leak reversal potential

g_L

nS

Leak conductance

I_e

pA

Constant external input current

Spike adaptation parameters

a

nS

Subthreshold adaptation

b

pA

Spike-triggered adaptation

Delta_T

mV

Slope factor

tau_w

ms

Adaptation time constant

V_th

mV

Spike initiation threshold

V_peak

mV

Spike detection threshold

Synaptic parameters

tau_syn_ex

ms

Rise time of excitatory synaptic conductance (alpha function)

tau_syn_in

ms

Rise time of the inhibitory synaptic conductance (alpha function)

Integration parameters

gsl_error_tol

real

This parameter controls the admissible error of the GSL integrator. Reduce it if NEST complains about numerical instabilities

Sends

SpikeEvent

Receives

SpikeEvent, CurrentEvent, DataLoggingRequest

References

See also

iaf_psc_alpha, aeif_cond_exp

Examples using this model

None