Network attacks on multi-layer and multi-frequency functional connectivity graphs of magnetoencephalographic recordings from patients with Mild traumatic brain injuries
Το work with title Network attacks on multi-layer and multi-frequency functional connectivity graphs of magnetoencephalographic recordings from patients with Mild traumatic brain injuries by Koutalaki Maria-Eleni is licensed under Creative Commons Attribution 4.0 International
Bibliographic Citation
Maria-Eleni Koutalaki, "Network attacks on multi-layer and multi-frequency functional connectivity graphs of magnetoencephalographic recordings from patients with Mild traumatic brain injuries", Diploma Work, School of Electrical and Computer Engineering, Technical University of Crete, Chania, Greece, 2024
https://doi.org/10.26233/heallink.tuc.101576
Functional connectivity networks describe the relationships between different brain regions that work together to perform specific functions. The concept of "attacks" in these networks refers to controlled interventions conducted in experimental settings, aiming to study their resilience. These interventions involve reducing the weights of the connections between regions. The present study examines the impact of attacks on functional connectivity networks on brain source time series from magnetoencephalography (MEG) recordings of individuals with mild traumatic brain injury (mTBI). The study focuses on the creation and analysis of multi-layer and multi-frequency graphs to highlight differences between brain networks in individuals with mTBI and in healthy individuals. Amplitude Envelope Correlation (AEC) is used as a connectivity estimator for generating the relevant networks and the Orthogonal Minimum Spanning Tree (OMST) method is used to reduce non-significant network connections. The Small-World structure of brain networks is extracted, and scenarios of targeted and random attacks on network nodes are applied to assess the resilience and efficiency of brain connections. Attack analysis revealed that functional connectivity networks in individuals with mTBI show increased vulnerability compared to networks of healthy individuals, in both random and targeted network node attacks. Targeted attacks, particularly in the α, β, and γ2 frequency bands, caused a notable reduction in global efficiency (GE) in mTBI individuals, indicating an increased sensitivity to connectivity disruptions. The findings of this study make a significant contribution to understanding the structural and functional sensitivity of the brain subsequent to mTBI, providing new evidence for the importance of enhancing the resilience of brain connections.