Lead/Lag directionality is not generally equivalent to causality in nonlinear systems: Comparison of phase slope index and conditional mutual information
Language English Country United States Media print-electronic
Document type Journal Article, Research Support, Non-U.S. Gov't, Comparative Study
PubMed
38631615
DOI
10.1016/j.neuroimage.2024.120610
PII: S1053-8119(24)00105-8
Knihovny.cz E-resources
- Keywords
- Conditional mutual information, Coupling directionality, Cross-frequency coupling, EEG, Nonlinear systems, Phase slope index,
- MeSH
- Electroencephalography * methods MeSH
- Humans MeSH
- Models, Neurological MeSH
- Brain physiology MeSH
- Nonlinear Dynamics * MeSH
- Computer Simulation MeSH
- Signal Processing, Computer-Assisted MeSH
- Animals MeSH
- Check Tag
- Humans MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Comparative Study MeSH
Applications of causal techniques to neural time series have increased extensively over last decades, including a wide and diverse family of methods focusing on electroencephalogram (EEG) analysis. Besides connectivity inferred in defined frequency bands, there is a growing interest in the analysis of cross-frequency interactions, in particular phase and amplitude coupling and directionality. Some studies show contradicting results of coupling directionality from high frequency to low frequency signal components, in spite of generally considered modulation of a high-frequency amplitude by a low-frequency phase. We have compared two widely used methods to estimate the directionality in cross frequency coupling: conditional mutual information (CMI) and phase slope index (PSI). The latter, applied to infer cross-frequency phase-amplitude directionality from animal intracranial recordings, gives opposite results when comparing to CMI. Both metrics were tested in a numerically simulated example of unidirectionally coupled Rössler systems, which helped to find the explanation of the contradictory results: PSI correctly estimates the lead/lag relationship which, however, is not generally equivalent to causality in the sense of directionality of coupling in nonlinear systems, correctly inferred by using CMI with surrogate data testing.
References provided by Crossref.org
