STP

STP(tau_rec=100.0, tau_facil=0.01, U=0.5)

Synapse exhibiting short-term facilitation and depression.

Implemented using the model of Tsodyks, Markram et al.:

Tsodyks, Uziel and Markram (2000) Synchrony Generation in Recurrent Networks with Frequency-Dependent Synapses. Journal of Neuroscience 20:RC50

Note that the time constant of the post-synaptic current is set in the neuron model, not here.

Equivalent code:

STP = ann.Synapse(
    parameters = dict(
        tau_rec = 100.0,
        tau_facil = 0.01,
        U = 0.5,
    ),
    equations = [
        ann.Variable('dx/dt = (1 - x)/tau_rec', init = 1.0, method='event-driven'),
        ann.Variable('du/dt = (U - u)/tau_facil', init = 0.5, method='event-driven'),
    ],
    pre_spike="""
        g_target += w * u * x
        x *= (1 - u)
        u += U * (1 - u)
    """
)

Parameters

Name	Type	Description	Default
tau_rec		depression time constant (ms).	100.0
tau_facil		facilitation time constant (ms).	0.01
U		use parameter.	0.5