2026-06-27T23:19:40Zhttps://docta.ucm.es/rest/oai/request
oai:docta.ucm.es:20.500.14352/949792025-03-18T15:17:32Zcom_20.500.14352_14col_20.500.14352_15
Docta Complutense author Shumbayawonda, Elizabeth author López Sanz, David author Bruña Fernández, Ricardo author Serrano Martínez, Noelia author Fernández Lucas, Alberto Amable author Maestu Unturbe, Fernando author Abásolo, Daniel 2024-01-24T09:27:45Z 2024-01-24T09:27:45Z 2020-02 1388-2457 10.1016/j.clinph.2019.11.023 https://hdl.handle.net/20.500.14352/94979 https://www.sciencedirect.com/science/article/pii/S1388245719313203 Objective To analyse magnetoencephalogram (MEG) signals with Lempel-Ziv Complexity (LZC) to identify the regions of the brain showing changes related to cognitive decline and Alzheimeŕs Disease (AD). Methods LZC was used to study MEG signals in the source space from 99 participants (36 male, 63 female, average age: 71.82 ± 4.06) in three groups (33 subjects per group): healthy (control) older adults, older adults with subjective cognitive decline (SCD), and adults with mild cognitive impairment (MCI). Analyses were performed in broadband (2–45 Hz) and in classic narrow bands (theta (4–8 Hz), alpha (8–12 Hz), low beta (12–20 Hz), high beta (20–30 Hz), and, gamma (30–45 Hz)). Results LZC was significantly lower in subjects with MCI than in those with SCD. Moreover, subjects with MCI had significantly lower MEG complexity than controls and SCD subjects in the beta frequency band. Lower complexity was correlated with smaller hippocampal volumes. Conclusions Brain complexity – measured with LZC – decreases in MCI patients when compared to SCD and healthy controls. This decrease is associated with a decrease in hippocampal volume, a key feature in AD progression. Significance This is the first study to date characterising the changes of brain activity complexity showing the specific spatial pattern of the alterations as well as the morphological correlations throughout preclinical stages of AD. eng Complexity changes in preclinical Alzheimer’s disease: An MEG study of subjective cognitive decline and mild cognitive impairment journal article 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URL https://docta.ucm.es/bitstreams/100eb57a-680a-4b7a-b92f-d3d3e2a1b055/download File MD5 563dd3576adfde1cbf3bb130b5fdc02e 557793 application/pdf Complexity changes submitted version.pdf URL https://docta.ucm.es/bitstreams/f1bc51c4-3e81-4af2-9e14-2971e3c6ed53/download File MD5 db3554e495012c7aa8839321279376f7 48414 text/plain Complexity changes submitted version.pdf.txt