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Interplay between synaptic delays and propagation delays in neural field equations. (English) Zbl 1284.34116

Summary: Neural field equations describe the activity of neural populations at a mesoscopic level. Although the early derivation of these equations introduced space-dependent delays coming from the finite speed of signal propagation along axons, there have been few studies concerning their role in shaping the (nonlinear) dynamics of neural activity. This is mainly due to the lack of analytical tractable models. On the other hand, constant delays have been introduced to model the synaptic transmission and the spike initiation dynamics. By incorporating the two kinds of delays into the neural field equations, we are able to find the Hopf bifurcation curves analytically, which produces many Hopf-Hopf interactions. We use normal theory to study two different types of connectivity that reveal a surprisingly rich dynamical portrait. In particular, the shape of the connectivity strongly influences the spatiotemporal dynamics.

MSC:

34K30 Functional-differential equations in abstract spaces
34K17 Transformation and reduction of functional-differential equations and systems, normal forms
34K19 Invariant manifolds of functional-differential equations
45G15 Systems of nonlinear integral equations
45P05 Integral operators
46E35 Sobolev spaces and other spaces of “smooth” functions, embedding theorems, trace theorems
58C40 Spectral theory; eigenvalue problems on manifolds
92B20 Neural networks for/in biological studies, artificial life and related topics
92C20 Neural biology
34K18 Bifurcation theory of functional-differential equations
34K20 Stability theory of functional-differential equations

Software:

dde23
Full Text: DOI