Asymmetric two-trace model for STDP

ECHEVESTE, RODRIGO; GROS, CLAUDIUS

Congreso; DPG-Frühjahrstagung (German Physical Society Meeting) 2014, Condensed Matter Section; 2014

In the present work we propose a simple model formulating synapticpotentiation and depression in terms of two interacting traces, rep-resenting the fraction of open NMDA receptors and the Ca 2+ con-centration in the post-synaptic neuron, respectively. These two tracesthen determine the evolution of the synaptic weight. We first test thatthe standard STDP curve for low frequency trains of pairs of pre- andpost-synaptic spikes is obtained and we then evaluate high frequencyeffects. Secondly, we study triplets. In this case, we are interested innon-linear effects and, in particular, in possible asymmetric responseto pre-post inversion.Having a low number of parameters and composed of only polyno-mial differential equations, the model is able nonetheless to reproducekey features of LTP and LTD. Moreover, since the parameters of themodel are easily related to the dynamical properties of the synapse, itpermits to make a connection between the observed synaptic weightchange and the behaviour of the underlying traces.