aeif_psc_delta_clopath – Adaptive exponential integrate-and-fire neuron ======================================================================= 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 occurred to mimic 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. 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. For implementation details see the `aeif_models_implementation <../model_details/aeif_models_implementation.ipynb>`_ notebook. See also [2]_. Parameters ++++++++++ The following parameters can be set in the status dictionary. =========== ====== =================================================== **Dynamic state variables** ----------------------------------------------------------------------- V_m mV Membrane potential w pA Spike-adaptation current z pA Spike-adaptation current V_th mV Adaptive spike initiation threshold u_bar_plus mV Low-pass filtered Membrane potential u_bar_minus mV Low-pass filtered Membrane potential u_bar_bar mV Low-pass filtered u_bar_minus =========== ====== =================================================== ================== ======= ================================================= **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 tau_u_bar_plus ms Time constant of u_bar_plus tau_u_bar_minus ms Time constant of u_bar_minus tau_u_bar_bar ms Time constant of u_bar_bar ================== ======= ================================================= ========== ====== =================================================== **Spike adaptation parameters** ---------------------------------------------------------------------- a nS Subthreshold adaptation b pA Spike-triggered adaptation Delta_T mV Slope factor tau_w ms Adaptation time constant tau_z ms Spike afterpotential current time constant I_sp pA Depolarizing spike afterpotential current magnitude V_peak mV Spike detection threshold V_th_max mV Value of V_th after a spike V_th_rest mV Resting value of V_th ========== ====== =================================================== ============= ======= ======================================================= **Clopath rule parameters** ----------------------------------------------------------------------------- A_LTD 1/mV Amplitude of depression A_LTP 1/mV^2 Amplitude of facilitation theta_plus mV Threshold for u theta_minus mV Threshold for u_bar_[plus/minus] A_LTD_const boolean 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 real Delay with which u_bar_[plus/minus] are processed to compute the synaptic weights. U_ref_squared real Reference value for u_bar_bar_^2. ============= ======= ======================================================= ======= ====== ============================================================= **Other parameters** ----------------------------------------------------------------------------- t_clamp ms Duration of clamping of Membrane potential after a spike V_clamp mV Value to which the Membrane potential is clamped ======= ====== ============================================================= ============= ======= ========================================================= **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 ++++++++++ .. [1] Clopath et al. (2010). Connectivity reflects coding: a model of voltage-based STDP with homeostasis. Nature Neuroscience 13(3):344-352. DOI: https://doi.org/10.1038/nn.2479 .. [2] Clopath and Gerstner (2010). Voltage and spike timing interact in STDP – a unified model. Frontiers in Synaptic Neuroscience. 2:25 DOI: https://doi.org/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 See also ++++++++ :doc:`Neuron `, :doc:`Adaptive Threshold `, :doc:`Integrate-And-Fire `, :doc:`Clopath Plasticity `, :doc:`Current-Based `