title: Noise-enhanced coupling between two oscillators with long-term plasticity.
abstract: Spike timing-dependent plasticity is a fundamental adaptation mechanism of the nervous system. It induces structural changes of synaptic connectivity by regulation of coupling strengths between individual cells depending on their spiking behavior. As a biophysical process its functioning is constantly subjected to natural fluctuations. We study theoretically the influence of noise on a microscopic level by considering only two coupled neurons. Adopting a phase description for the neurons we derive a two-dimensional system which describes the averaged dynamics of the coupling strengths. We show that a multistability of several coupling configurations is possible, where some configurations are not found in systems without noise. Intriguingly, it is possible that a strong bidirectional coupling, which is not present in the noise-free situation, can be stabilized by the noise. This means that increased noise, which is normally expected to desynchronize the neurons, can be the reason for an antagonistic response of the system, which organizes itself into a state of stronger coupling and counteracts the impact of noise. This mechanism, as well as a high potential for multistability, is also demonstrated numerically for a coupled pair of Hodgkin-Huxley neurons.
authors.affiliation: Weierstrass Institute for Applied Analysis and Stochastics, Berlin, Germany.
authors.forename: Leonhard
authors.initials: L
authors.lastname: Lücken
authors.affiliation: Institute of Neuroscience and Medicine - Neuromodulation, Jülich Research Center, Jülich, Germany.
authors.forename: Oleksandr V
authors.initials: OV
authors.lastname: Popovych
authors.affiliation: Institute of Neuroscience and Medicine - Neuromodulation, Jülich Research Center, Jülich, Germany.|Department of Neurosurgery, Stanford University, Stanford, California, USA.|Department of Neuromodulation, University of Cologne, Cologne, Germany.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Tass
authors.affiliation: Weierstrass Institute for Applied Analysis and Stochastics, Berlin, Germany.|Institute of Mathematics, Technical University of Berlin, Berlin, Germany.
authors.forename: Serhiy
authors.initials: S
authors.lastname: Yanchuk
mesh_terms: D008959:Models, Neurological; D009473:Neuronal Plasticity; D009474:Neurons / Q000166:cytology*