Long and short-term synaptic plasticity and the formation of working memory: A case study

摘要

We study the collective behaviour of recurrent networks of integrate-and-fire neurons, connected by synapses whose efficacies are subjected to a spike-driven, and rate sensitive, Hebbian LTP and a homosynaptic depression, as well as a short-term, frequency dependent Depression (STD). Through a mean field analysis, and numerical simulations of the couled Neural and synaptic dynamics, we show how repeated stimulations of the network can Dynamically produce a synaptic structure supporting persistent, collective, stimulus-selective Activity, that have been proposed since long as a substrate for 'working memory'. We discuss Contraints relevant to the stability of the 'learning' process, and the related role of long-term Synaptic depression as well as the effects of inclusion of STD.