Towards a dynamical understanding of microstate analysis of M/EEG data

0576873 - ÚI 2024 RIV NL eng J - Journal Article
Jajcay, Nikola - Hlinka, Jaroslav
Towards a dynamical understanding of microstate analysis of M/EEG data.
Neuroimage. Roč. 281, November 2023 (2023), č. článku 120371. ISSN 1053-8119. E-ISSN 1095-9572
R&D Projects: GA ČR(CZ) GA21-32608S
Grant - others:Ministerstvo školství, mládeže a tělovýchovy - GA MŠk(CZ) LM2018140
Institutional support: RVO:67985807
Keywords : Microstates * M/EEG resting-state * Gaussian model * Microstate properties * VAR model
OECD category: Neurosciences (including psychophysiology
Impact factor: 5.7, year: 2022
Method of publishing: Open access
https://dx.doi.org/10.1016/j.neuroimage.2023.120371

One of the interesting aspects of EEG data is the presence of temporally stable and spatially coherent patterns of activity, known as microstates, which have been linked to various cognitive and clinical phenomena. However, there is still no general agreement on the interpretation of microstate analysis. Various clustering algorithms have been used for microstate computation, and multiple studies suggest that the microstate time series may provide insight into the neural activity of the brain in the resting state. This study addresses two gaps in the literature. Firstly, by applying several state-of-the-art microstate algorithms to a large dataset of EEG recordings, we aim to characterise and describe various microstate algorithms. We demonstrate and discuss why the three “classically” used algorithms ((T)AAHC and modified K-Means) yield virtually the same results, while HMM algorithm generates the most dissimilar results. Secondly, we aim to test the hypothesis that dynamical microstate properties might be, to a large extent, determined by the linear characteristics of the underlying EEG signal, in particular, by the cross-covariance and autocorrelation structure of the EEG data. To this end, we generated a Fourier transform surrogate of the EEG signal to compare microstate properties. Here, we found that these are largely similar, thus hinting that microstate properties depend to a very high degree on the linear covariance and autocorrelation structure of the underlying EEG data. Finally, we treated the EEG data as a vector autoregression process, estimated its parameters, and generated surrogate stationary and linear data from fitted VAR. We observed that such a linear model generates microstates highly comparable to those estimated from real EEG data, supporting the conclusion that a linear EEG model can help with the methodological and clinical interpretation of both static and dynamic human brain microstate properties.
Permanent Link: https://hdl.handle.net/11104/0346275


Research data: Supplementary material at publisher, Preprint at BiorXiv.org