Command: aeif_cond_exp

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Membrane
Name:
 aeif_cond_exp - Conductance based exponential integrate-and-fire neuron model according to Brette and Gerstner (2005).
Description:
 

aeif_cond_exp is the adaptive exponential integrate and fire neuron
according to Brette and Gerstner (2005), with post-synaptic
conductances in the form of truncated exponentials.

This implementation uses the embedded 4th order Runge-Kutta-Fehlberg
solver with adaptive stepsize 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*Delta_T*exp((V-V_T)/Delta_T)-g_e(t)(V-E_e) -g_i(t)(V-E_i)-w +I_e

and

tau_w * dw/dt= a(V-E_L) -W


Note that the spike detection threshold V_peak is automatically set to
V_th+10 mV to avoid numerical instabilites that may result from
setting V_peak too high.
Parameters:
 
The following parameters can be set in the status dictionary.

Dynamic state variables:
  V_m        double - Membrane potential in mV
  g_ex       double - Excitatory synaptic conductance in nS.
  g_in       double - Inhibitory synaptic conductance in nS.
  w          double - Spike-adaptation current in pA.
Parameters:
  C_m        double - Capacity of the membrane in pF
  t_ref      double - Duration of refractory period in ms. 
  V_reset    double - Reset value for V_m after a spike. In mV.
  E_L        double - Leak reversal potential in mV. 
  g_L        double - Leak conductance in nS.
  I_e        double - Constant external input current in pA.

Spike adaptation parameters:
  a          double - Subthreshold adaptation in nS.
  b          double - Spike-triggered adaptation in pA.
  Delta_T    double - Slope factor in mV
  tau_w      double - Adaptation time constant in ms
  V_t        double - Spike initiation threshold in mV
  V_peak     double - Spike detection threshold in mV.

Synaptic parameters
  E_ex       double - Excitatory reversal potential in mV.
  tau_syn_ex double - Rise time of excitatory synaptic conductance in ms (exp function).
  E_in       double - Inhibitory reversal potential in mV.
  tau_syn_in double - Rise time of the inhibitory synaptic conductance in ms (exp function).

Integration parameters
  gsl_error_tol  double - This parameter controls the admissible error of the GSL integrator.
                          Reduce it if NEST complains about numerical instabilities.
Author:
 Adapted from aeif_cond_alpha by Lyle Muller
Sends:
 SpikeEvent
Receives:
 SpikeEvent, CurrentEvent, DataLoggingRequest
References:
 Brette R and Gerstner W (2005) Adaptive Exponential Integrate-and-Fire Model as 
            an Effective Description of Neuronal Activity. J Neurophysiol 94:3637-3642
SeeAlso:iaf_cond_exp aeif_cond_alpha
Source:
 /home/abuild/rpmbuild/BUILD/nest-2.4.1/models/aeif_cond_exp.h

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