Cortical neurons are typically driven by several thousand synapses. The precise spatiotemporal pattern formed by these inputs can modulate the response of a post-synaptic cell. In this work, we explore how the temporal structure of pre-synaptic inhibitory and excitatory inputs impact the post-synaptic firing of a conductance-based integrate and fire neuron. Both the excitatory and inhibitory input was modeled by renewal gamma processes with varying shape factors for modeling regular and temporally random Poisson activity. We demonstrate that the temporal structure of mutually independent inputs affects the post-synaptic firing, while the strength of the effect depends on the firing rates of both the excitatory and inhibitory inputs. In a second step, we explore the effect of temporal structure of mutually independent inputs on a simple version of Hebbian learning, i.e., hard bound spike-timing-dependent plasticity. We explore both the equilibrium weight distribution and the speed of the transient weight dynamics for different mutually independent gamma processes. We find that both the equilibrium distribution of the synaptic weights and the speed of synaptic changes are modulated by the temporal structure of the input. Finally, we highlight that the sensitivity of both the post-synaptic firing as well as the spike-timing-dependent plasticity on the auto-structure of the input of a neuron could be used to modulate the learning rate of synaptic modification.
Keywords: spike train, auto-structure, STDP, temporal correlations, integrate and fire, non-Poissonian
Citation: Scheller B, Castellano M, Vicente R and Pipa G (2011) Spike train auto-structure impacts post-synaptic firing and timing-based plasticity. Front. Comput. Neurosci. 5:60. doi: 10.3389/fncom.2011.00060
Received: 17 November 2010;
Accepted: 29 November 2011;
Published online: 16 December 2011.
Edited by:Hava T. Siegelmann, Rutgers University, USA
Reviewed by:Markus Diesmann, RIKEN Brain Science Institute, Japan
Copyright: © 2011 Scheller, Castellano, Vicente and Pipa. This is an open-access article distributed under the terms of the Creative Commons Attribution Non Commercial License, which permits non-commercial use, distribution, and reproduction in other forums, provided the original authors and source are credited.
*Correspondence: Gordon Pipa, Institute of Cognitive Science, University of Osnabrück, Albrechtstraße 28, 49069 Osnabrück, Germany. e-mail: firstname.lastname@example.org
†Bertram Scheller and Marta Castellano have contributed equally to this work.