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arXiv · 1605.07977

Instability to a heterogeneous oscillatory state in randomly connected recurrent networks with delayed interactions

Abstract

Oscillatory dynamics are ubiquitous in biological networks. Possible sources of oscillations are well understood in low-dimensional systems, but have not been fully explored in high-dimensional networks. Here we study large networks consisting of randomly coupled rate units. We identify a novel type of bifurcation in which a continuous part of the eigenvalue spectrum of the linear stability matrix crosses the instability line at non-zero-frequency. This bifurcation occurs when the interactions are delayed and partially anti-symmetric, and leads to a heterogeneous oscillatory state in which oscillations are apparent in the activity of individual units, but not on the population-average level.

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Célian Bimbard, Erwan Ledoux, Srdjan Ostojic. 2016-05-25. Instability to a heterogeneous oscillatory state in randomly connected recurrent networks with delayed interactions. https://doi.org/10.1103/physreve.94.062207

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