Open-source tools for dynamical analysis of Liley's mean-field cortex model

Highlights

• A parallel open-source implementation of Liley's mean-field cortex model, in PETSc.

• We implement fully implicit time integration of nonlinear and variational equations.

• We perform equilibrium continuation, with computation of inhomogeneous eigenmodes.

• We compute periodic solutions with Newton–Krylov iteration.

Abstract

Mean-field models of the mammalian cortex treat this part of the brain as a two-dimensional excitable medium. The electrical potentials, generated by the excitatory and inhibitory neuron populations, are described by nonlinear, coupled, partial differential equations that are known to generate complicated spatio-temporal behaviour. We focus on the model by Liley et al. (Network: Computation in Neural Systems 13 (2002) 67–113). Several reductions of this model have been studied in detail, but a direct analysis of its spatio-temporal dynamics has, to the best of our knowledge, never been attempted before. Here, we describe the implementation of implicit time-stepping of the model and the tangent linear model, and solving for equilibria and time-periodic solutions, using the open-source library PETSc. By using domain decomposition for parallelization, and iterative solving of linear problems, the code is capable of parsing some dynamics of a macroscopic slice of cortical tissue with a sub-millimetre resolution.