MesoNet: archived STDP trace parameters

STDP constants + handlers together. find where on_post is attached, not just where the string is defined

Location: base_model/mnistV1.py, the stdp_eqs, stdp_eqs_pre and stdp_eqs_post strings. The prototype uses taupre = taupost = tau, with tau = 1*ms, wmax = 0.01, Apre = 0.01, and Apost = -Apre*taupre/taupost*1.05.

dapre/dt  = -apre/taupre   (event-driven)
dapost/dt = -apost/taupost (event-driven)
pre:  apre += Apre;   w = clip(w + apost, 0, wmax)
post: apost += Apost; w = clip(w + apre,  0, wmax)

This is a compact transcription of the archive, not a newly executed model. Trace decay and event updates need to be considered together when deciding the sign of the effective learning window.

Review issue: the shown connA2B construction attaches stdp_eqs_pre to its two presynaptic event pathways, but the printed block does not visibly attach stdp_eqs_post via on_post. Recover the executable revision and confirm whether postsynaptic trace updates are registered elsewhere. Otherwise, having a string named stdp_eqs_post does not establish that it runs.

Related check: both polarity pathways use the same presynaptic trace update. Specify whether polarity should affect the learning rule or only the downstream state change.

STDP traces and event definitions