Sustained activity with low firing rate in a recurrent network regulated by spike-timing-dependent plasticity

In order to study roles of spike-timing-dependent plasticity (STDP) at the network level, we applied STDP to a model of the cortical recurrent network. We found that STDP brought self-organization of a bistable neural activity that is essential for the working memory function. Furthermore, our simulations showed that the typical two ring patterns during the persistent activity were achieved, which depend on the time window of STDP; the short time window (∼10 ms) yielded an asynchronous ring activity, whereas the longer one (¿20 ms) produced a synchronous spike packet propagating along a chain of cell assemblies. c © 2002 Elsevier Science B.V. All rights reserved.