Differential influence of sinusoidal and noisy inputs on synaptic connections in a network with STDP

¹ Institute for Theoretical Physics and Astrophysics, University of Kiel - 24098 Kiel, Germany, EU
² Institute of Medical Psychology and Behavioral Neurobiology, University of Tübingen 72074 Tübingen, Germany, EU
³ Institute for Neuroendocrinologie, University of Lübeck - 23562 Lübeck, Germany, EU
⁴ Institute for Neuro- and Bioinformatics, University of Lübeck - 23538 Lübeck, Germany, EU
⁵ Graduate School for Computing in Medicine and Life Science, University of Lübeck 23538 Lübeck, Germany, EU

^a ngo@inb.uni-luebeck.de

Received: 18 October 2011
Accepted: 24 April 2012

Abstract

We hypothesize that the type of cortical network activation influences synaptic connectivity in the network, eventually expressed in an altered responsiveness to external stimuli. Our predictions are based on a time discrete canonical model of spike-time–dependent plasticity. The results show that, at a given synaptic connection strength in the network, sinusoidal input to the network can decrease synaptic potentiation whereas uncorrelated noise increases synaptic potentiation, implying that these opposing effects manifest themselves in respective decreases and increases of the network response to an external stimulus. These predictions are in qualitative agreement with visually evoked responses obtained in humans after 9 hour periods of visual deprivation (used to increase sinusoidal EEG alpha-activity in cortical networks) or normal daytime vision (as an approximate of noise input).