This Connection class implements the Tsodyks Markram synapse model [1] for short-term plasticity. See sim_epsp_stp for an example.

STPConnection * con = new STPConnection(poisson,neuron,w,1.0,GLUT);

is the standard usage to set up a connection object between the presynaptic SpikingGroup poisson and the postsynaptic NeuronGroup neuron. In the example the connection assumes random sparse connectivity with weight w and the sparseness=1.0 which targets glutamate receptors (cf. TransmitterType).

Setting up the model parameters is illustrated in the following example where we assume a synapse with U=0.2, tau_d=200ms and tau_f=50ms (for details on the meanings of the different time parameters see [2]). Note, however, that the U parameter is split in this implementation so that one can combine a different spike-triggered jump with a different resting value of the u variable in the model.

// Sets STP parameters (depression dominated)
double U = 0.2;
double taud = 200e-3; // s
double tauf = 50e-3;  // s
 
// Passes the parameters to the connection instance
con->set_tau_d(taud);
con->set_tau_f(tauf);
con->set_ujump(U);
con->set_urest(U);

[1] Markram, H., Wang, Y., Tsodyks, M., 1998. Differential signaling via the same axon of neocortical pyramidal neurons. Proc Natl Acad Sci U S A 95, 5323–5328.

[2] Mongillo, G., Barak, O., Tsodyks, M., 2008. Synaptic Theory of Working Memory. Science 319, 1543–1546. doi:10.1126/science.1150769

Notes on parallelizing short-term plasticity