A calcium-based simplified model for a large diversity of spike-timing dependent plasticity

Spike-timing dependent plasticity (STDP) is a form of synaptic modification, which depends on relative timings of presynaptic and postsynaptic spikes. In this paper, a novel calcium-based simple STDP model is presented, where the model is described by an ordinary differential equation having only two state variables: one represents intracellular calcium density and the other represents fraction of open state NMDARs. It is shown that, in spite of the simplicity of the model, it can reproduce STDP characteristics that are experimentally observed in various brain areas (e.g., layer 2/3, 5 visual cortical slices and hippocampal cultures) with respect to various patterns of presynaptic and postsynaptic spikes. In addition, comparisons to other STDP models are given, and advantages and significances of the presented model are clarified.