Spike-timing-dependent synaptic plasticity can form “zero lag links” for cortical oscillations.

Abstract

We study the impact of spike-timing-dependent synaptic plasticity (STDP) on coherent gamma activity between distant cortical regions with reciprocal projections. Our simulation network consists of two areas and includes a STDP model re ecting e cacy suppression between pre/ postsynaptic spike pairs as found in recent experiments during stimulation with spike trains (Nature 416 (2002) 433). We ÿnd that STDP in conjunction with oscillatory common input strengthens synapses with delays around multiples of the oscillation period. As a result, intrinsic excitatory interactions between the areas express in gamma waves with zero lag synchrony (instead of unphysiological anti-phase synchrony without STDP). We discuss the impact of e cacy suppression on learning convergence and robustness.

Stimulus-dependent synchronization in delayed-coupled neuronal networks

“…In this study we have shown that a network of neuronal oscillators with delayed connections can switch between synchronous network oscillations and incoherent firing activity, when the input to the network changes. Different aspects of synchronization of neuronal oscillators have been extensively studied in recent decades and the possible role of the type of synapses 77 78 , synaptic plasticity 79 80 81 82 83 , and effect of transmission delays 84 85 have been explored. It is well-known that the role of the synaptic connections in synchronizing the neuronal oscillators can be identified once the phase resetting curve of the neurons, inter-spike intervals and the time delay are known 55 86 87 .…”

Dendritic and Axonal Propagation Delays Determine Emergent Structures of Neuronal Networks with Plastic Synapses

“…Early studies on the effect of STDP showed that it enhances network synchronization through promoting causal links263536. However, it has been shown that considering propagation delays in the models, firing in synchrony induces long-term depression (LTD) and decouples the neurons373839. Later, an intermediate effect has been reported showing that in the presence of propagation delays, STDP promotes the self-organization of recurrent networks into mixture states at the border between randomness and synchrony12.…”

Zero delay synchronization of chaos in coupled map lattices

“…From the form of analytical estimates in Eqns. (19,21) and (24), it might appear as though z-CML has no role to play in synchronizing the coupled dynamics. The contribution of z-CML enters the x-and y-CML through the mutual coupling terms with the delay k.…”

“…A variant of this scheme has been used to propose a method for bidirectional secure communication using delay coupled oscillators [18]. Simultaneously, the modeling and analysis of zero lag synchronization maintained over large distances in neurons is beginning to take shape [19].…”