vogels_sprekeler_synapse – Synapse type for symmetric spike-timing dependent plasticity with constant depression
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Description
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``vogels_sprekeler_synapse`` is a connector to create synapses with symmetric
spike time dependent plasticity and constant depression (as defined in [1]_).
The learning rule is symmetric, that is, the synapse is strengthened
irrespective of the order of the pre- and postsynaptic spikes. Each
pre-synaptic spike also causes a constant depression of the synaptic weight
which differentiates this rule from other classical STDP rules.

.. warning::

   This synaptic plasticity rule does not take
   :ref:`precise spike timing <sim_precise_spike_times>` into
   account. When calculating the weight update, the precise spike time part
   of the timestamp is ignored.

Parameters
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======  ======  =========================================================
 tau    ms      Time constant of STDP window, potentiation
 Wmax   real    Maximum allowed weight
 eta    real    Learning rate
 alpha  real    Constant depression (= 2 * tau * target firing rate in
                [1]_)
======  ======  =========================================================

Transmits
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SpikeEvent

References
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.. [1] Vogels et al. (2011). Inhibitory plasticity balances excitation and
       inhibition in sensory pathways and memory networks. Science,
       334(6062):1569-1573. DOI: https://doi.org/10.1126/science.1211095


Examples using this model
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.. listexamples:: vogels_sprekeler_synapse