Investigating the spectral features of the brain meso-scale structure at rest

• Main Authors: Avanzino, L. (Author), Chiappalone, M. (Author), Iandolo, R. (Author), Mantini, D. (Author), Semprini, M. (Author), Sona, D. (Author)
• Format: Article
• Language: English
• Published: John Wiley and Sons Inc 2021
• Subjects: adult; Adult; article; assortativity; brain; Brain; brain region; Brain Waves; community detection; community structure; connectome; Connectome; controlled study; electroencephalogram; electroencephalography; Electroencephalography; female; Female; frequency-specificity; human; human experiment; Humans; male; Male; meso-scale; nerve cell network; Nerve Net; network neuroscience; neuroscience; physiology; resting state; stochastic model; young adult; Young Adult
• Online Access: View Fulltext in Publisher

 Recent studies provide novel insights into the meso-scale organization of the brain, highlighting the co-occurrence of different structures: classic assortative (modular), disassortative, and core-periphery. However, the spectral properties of the brain meso-scale remain mostly unexplored. To fill this knowledge gap, we investigated how the meso-scale structure is organized across the frequency domain. We analyzed the resting state activity of healthy participants with source-localized high-density electroencephalography signals. Then, we inferred the community structure using weighted stochastic block-model (WSBM) to capture the landscape of meso-scale structures across the frequency domain. We found that different meso-scale modalities co-exist and are diversely organized over the frequency spectrum. Specifically, we found a core-periphery structure dominance, but we also highlighted a selective increase of disassortativity in the low frequency bands (<8 Hz), and of assortativity in the high frequency band (30–50 Hz). We further described other features of the meso-scale organization by identifying those brain regions which, at the same time, (a) exhibited the highest degree of assortativity, disassortativity, and core-peripheriness (i.e., participation) and (b) were consistently assigned to the same community, irrespective from the granularity imposed by WSBM (i.e., granularity-invariance). In conclusion, we observed that the brain spontaneous activity shows frequency-specific meso-scale organization, which may support spatially distributed and local information processing. © 2021 The Authors. Human Brain Mapping published by Wiley Periodicals LLC.