Reconstruction of phase-amplitude dynamics from electrophysiological signals
Abstract
We present a novel method of reconstructing the phase-amplitude dynamics directly from measured electrophysiological signals to estimate the coupling between brain regions. For this purpose, we use the recent advances in the field of phase-amplitude reduction of oscillatory systems, which allow the representation of an uncoupled oscillatory system as a phase-amplitude oscillator in a unique form using transformations (parameterizations) related to the eigenfunctions of the Koopman operator. By combining the parameterization method and the Fourier-Laplace averaging method for finding the eigenfunctions of the Koopman operator, we developed a method of assessing the transformation functions from the signals of the interacting oscillatory systems. The resulting reconstructed dynamical system is a network of phase-amplitude oscillators with the interactions between them represented as coupling functions in phase and amplitude coordinates.
Keywords
Cite
@article{arxiv.2406.05073,
title = {Reconstruction of phase-amplitude dynamics from electrophysiological signals},
author = {Azamat Yeldesbay and Gemma Huguet and Silvia Daun},
journal= {arXiv preprint arXiv:2406.05073},
year = {2025}
}