aeif_cond_alpha_astro – Conductance based exponential integrate-and-fire neuron model with support for neuron-astrocyte interactions

Description

aeif_cond_alpha_astro is an adaptive exponential integrate-and-fire neuron (AdEx) that can receive inputs from astrocytes, in addition to receiving synaptic inputs from other neurons. It is adapted from the standard NEST implementation of AdEx neurons (aeif_cond_alpha). The connection with astrocytes is established through sic_connection, which sends slow inward current (SIC) from an astrocyte to aeif_cond_alpha_astro.

The membrane potential is given by the following differential equation (adapted from aeif_cond_alpha):

\[\begin{split}C_m \frac{dV}{dt} = -g_L(V-E_L)+g_L\Delta_T\exp\left(\frac{V-V_{th}}{\Delta_T}\right) - g_e(t)(V-E_e) \\ -g_i(t)(V-E_i)-w +I_e + I_{\text{SIC}}\end{split}\]

and

\[\tau_w \frac{dw}{dt} = a(V-E_L) - w\]

Here, \(I_{\text{SIC}}\) is the sum of slow inward currents received from all astrocytes connected to the neuron. The other parameters and variables are the same as in aeif_cond_alpha.

For implementation details of the adaptive exponential integrate-and-fire neuron model, 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
g_ex	nS	Excitatory synaptic conductance
dg_ex	nS/ms	First derivative of g_ex
g_in	nS	Inhibitory synaptic conductance
dg_in	nS/ms	First derivative of g_in
w	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
E_ex	mV	Excitatory reversal potential
tau_syn_ex	ms	Rise time of the excitatory synaptic conductance (alpha function)
E_in	mV	Inhibitory reversal potential
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, SICEvent

References

[1]

Brette R and Gerstner W (2005). Adaptive exponential integrate-and-fire model as an effective description of neuronal activity. Journal of Neurophysiology. 943637-3642 DOI: https://doi.org/10.1152/jn.00686.2005

See also

Neuron, Integrate-And-Fire, Adaptive Threshold, Conductance-Based, Astrocyte

Examples using this model

• A small neuron-astrocyte network

• A tripartite interaction between two neurons and one astrocyte

• Random balanced network with astrocytes