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Sex Differences in the Complexity of Healthy Older Adults’ Magnetoencephalograms

Shumbayawonda, Elizabeth, Abasolo, Daniel, López-Sanz, David, Bruña, Ricardo, Maestu, Fernando and Fernández, Alberto (2019) Sex Differences in the Complexity of Healthy Older Adults’ Magnetoencephalograms Entropy, 21 (8).

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The analysis of resting-state brain activity recording in magnetoencephalograms (MEGs) with new algorithms of symbolic dynamics analysis could help obtain a deeper insight into the functioning of the brain and identify potential differences between males and females. Permutation Lempel-Ziv complexity (PLZC), a recently introduced non-linear signal processing algorithm based on symbolic dynamics, was used to evaluate the complexity of MEG signals in source space. PLZC was estimated in a broad band of frequencies (2–45 Hz), as well as in narrow bands (i.e., theta (4–8 Hz), alpha (8–12 Hz), low beta (12–20 Hz), high beta (20–30 Hz), and gamma (30–45 Hz)) in a sample of 98 healthy elderly subjects (49 males, 49 female) aged 65–80 (average age of 72.71 ± 4.22 for males and 72.67 ± 4.21 for females). PLZC was significantly higher for females than males in the high beta band at posterior brain regions including the precuneus, and the parietal and occipital cortices. Further statistical analyses showed that higher complexity values over highly overlapping regions than the ones mentioned above were associated with larger hippocampal volumes only in females. These results suggest that sex differences in healthy aging can be identified from the analysis of magnetoencephalograms with novel signal processing methods.

Item Type: Article
Divisions : Faculty of Engineering and Physical Sciences > Mechanical Engineering Sciences
Authors :
López-Sanz, David
Bruña, Ricardo
Maestu, Fernando
Fernández, Alberto
Date : 15 August 2019
DOI : 10.3390/e21080798
Copyright Disclaimer : © 2019 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (
Uncontrolled Keywords : Permutation Lempel-Ziv complexity; Magnetoencephalography; Source space; Healthy aging; Sex differences
Additional Information : This article belongs to the Special Issue Entropy Applications in EEG/MEG.
Depositing User : Clive Harris
Date Deposited : 16 Aug 2019 09:04
Last Modified : 20 Aug 2019 14:40

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