Command: aeif_psc_delta_clopath

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Name:
aeif_psc_delta_clopath - Exponential integrate-and-fire neuron
model according to Clopath et al. (2010).
Description:
aeif_psc_delta_clopath is an implementation of the neuron model as it is used
in [1]. It is an extension of the aeif_psc_delta model and capable of
connecting to a Clopath synapse.

Note that there are two points that are not mentioned in the paper but
present in a MATLAB implementation by Claudia Clopath [3]. The first one is the
clamping of the membrane potential to a fixed value after a spike occured to
mimik a real spike and not just the upswing. This is important since the finite
duration of the spike influences the evolution of the convolved versions
(u_bar_[plus/minus]) of the membrane potential and thus the change of the
synaptic weight. Secondly, there is a delay with which u_bar_[plus/minus] are
used to compute the change of the synaptic weight.
Parameters:
The following parameters can be set in the status dictionary.

Dynamic state variables:
V_m double - Membrane potential in mV.
w double - Spike-adaptation current in pA.
z double - Spike-adaptation current in pA.
V_th double - Adaptive spike initiation threshold in mV.
u_bar_plus double - Low-pass filtered Membrane potential in mV.
u_bar_minus double - Low-pass filtered Membrane potential in mV.
u_bar_bar double - Low-pass filtered u_bar_minus in mV.

Membrane 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.
tau_plus double - Time constant of u_bar_plus.
tau_minus double - Time constant of u_bar_minus.
tau_bar_bar double - Time constant of u_bar_bar.

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_peak double - Spike detection threshold in mV.
V_th_max double - Value of V_th afer a spike in mV.
V_th_rest double - Resting value of V_th in mV.

Clopath rule parameters:
A_LTD double - Amplitude of depression in 1/mV.
A_LTP double - Amplitude of facilitation in 1/mV^2.
theta_plus double - threshold for u in mV.
theta_minus double - threshold for u_bar_[plus/minus] in mV.
A_LTD_const bool - Flag that indicates whether A_LTD_ should
be constant (true, default) or multiplied by
u_bar_bar^2 / u_ref_squared (false).
delay_u_bars double - Delay with which u_bar_[plus/minus] are processed
to compute the synaptic weights.
U_ref_squared double - Reference value for u_bar_bar_^2.

Other parameters:
t_clamp double - Duration of clamping of Membrane potential after a spike
in ms.
V_clamp double - Value to which the Membrane potential is clamped in mV.

Integration parameters:
gsl_error_tol double - This parameter controls the admissible error of the
GSL integrator. Reduce it if NEST complains about
numerical instabilities.

Note:

Neither the clamping nor the delayed processing of u_bar_[plus/minus] are
mentioned in [1]. However, they are part of an reference implementation
by Claudia Clopath et al. that can be found on ModelDB [3]. The clamping is
important to mimic a spike which is otherwise not described by the aeif neuron
model.
Require:
HAVE_GSL
Receives:
SpikeEvent, CurrentEvent, DataLoggingRequest
Sends:
SpikeEvent
References:
[1] Clopath et al. (2010) Connectivity reflects coding:
a model of voltage-based STDP with homeostasis.
Nature Neuroscience 13:3, 344--352
[2] Clopath and Gerstner (2010) Voltage and spike timing interact
in STDP – a unified model. Front. Synaptic Neurosci. 2:25
doi: 10.3389/fnsyn.2010.00025
[3] Voltage-based STDP synapse (Clopath et al. 2010) on ModelDB
https://senselab.med.yale.edu/ModelDB/showmodel.cshtml?model=144566&file=%2f
modeldb_package%2fVoTriCode%2faEIF.m
Author:
Jonas Stapmanns, David Dahmen, Jan Hahne
SeeAlso:
Source:
/usr/src/packages/BUILD/models/aeif_psc_delta_clopath.h
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