Copyright © 2012 Junfeng Sun et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
Functional neural connectivity is drawing increasing
attention in neuroscience research. To infer functional connectivity
from observed neural signals, various methods have been
proposed. Among them, phase synchronization analysis is an
important and effective one which examines the relationship
of instantaneous phase between neural signals but neglecting
the influence of their amplitudes. In this paper, we review the
advances in methodologies of phase synchronization analysis. In
particular, we discuss the definitions of instantaneous phase, the
indexes of phase synchronization and their significance test, the
issues that may affect the detection of phase synchronization
and the extensions of phase synchronization analysis. In practice,
phase synchronization analysis may be affected by observational
noise, insufficient samples of the signals, volume conduction,
and reference in recording neural signals. We make comments
and suggestions on these issues so as to better apply phase
synchronization analysis to inferring functional connectivity from
neural signals.