Front bifurcations in an excitatory neural network
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Published version
Author(s)
Bressloff, Paul C
Folias, Stefanos E
Type
Journal Article
Abstract
We show how a one-dimensional excitatory neural network can exhibit a symmetry breaking front bifurcation analogous to that found in reaction diffusion systems. This occurs in a homogeneous network when a stationary front undergoes a pitchfork bifurcation leading to bidirectional wave propagation. We analyze the dynamics in a neighborhood of the front bifurcation using perturbation methods, and we establish that a weak input inhomogeneity can induce a Hopf instability of the stationary front, leading to the formation of an oscillatory front or breather. We then carry out a stability analysis of stationary fronts in an exactly solvable model and use this to derive conditions for oscillatory fronts beyond the weak input regime. In particular, we show how wave propagation failure occurs in the presence of a large stationary input due to the pinning of a stationary front; a subsequent reductionin the strength of the input then generates a breather via a Hopf instability of the front. Finally, we derive conditions for the locking of a traveling front to a moving input, and we show how locking depends on both the amplitude and velocity of the input.
Date Issued
2004-01
Date Acceptance
2004-05-12
Citation
SIAM Journal on Applied Mathematics, 2004, 65 (1), pp.131-151
ISSN
0036-1399
Publisher
Society for Industrial and Applied Mathematics
Start Page
131
End Page
151
Journal / Book Title
SIAM Journal on Applied Mathematics
Volume
65
Issue
1
Copyright Statement
Copyright © 2004 Society for Industrial and Applied Mathematics.
Identifier
http://dx.doi.org/10.1137/s0036139903434481
Publication Status
Published
Date Publish Online
2004-09-24