title: Altered cross-frequency coupling in resting-state MEG after mild traumatic brain injury.
abstract: Cross-frequency coupling (CFC) is thought to represent a basic mechanism of functional integration of neural networks across distant brain regions. In this study, we analyzed CFC profiles from resting state Magnetoencephalographic (MEG) recordings obtained from 30 mild traumatic brain injury (mTBI) patients and 50 controls. We used mutual information (MI) to quantify the phase-to-amplitude coupling (PAC) of activity among the recording sensors in six nonoverlapping frequency bands. After forming the CFC-based functional connectivity graphs, we employed a tensor representation and tensor subspace analysis to identify the optimal set of features for subject classification as mTBI or control. Our results showed that controls formed a dense network of stronger local and global connections indicating higher functional integration compared to mTBI patients. Furthermore, mTBI patients could be separated from controls with more than 90% classification accuracy. These findings indicate that analysis of brain networks computed from resting-state MEG with PAC and tensorial representation of connectivity profiles may provide a valuable biomarker for the diagnosis of mTBI.
authors.affiliation: Digital Image and Signal Processing Laboratory, School of Electronic and Computer Engineering, Technical University of Crete, Chania 73100, Greece. Electronic address: mantonakakis@isc.tuc.gr.
authors.forename: Marios
authors.initials: M
authors.lastname: Antonakakis
authors.affiliation: Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University School of Medicine, Cardiff, United Kingdom; Cardiff University Brain Research Imaging Center (CUBRIC), School of Psychology, Cardiff University, Cardiff, United Kingdom; Artificial Intelligence and Information Analysis Laboratory, Department of Informatics, Aristotle University, Thessaloniki 54124, Greece; Neuroinformatics Group, Department of Informatics, Aristotle University of Thessaloniki, Thessaloniki, Greece. Electronic address: http://www.neuroinformatics.gr.
authors.forename: Stavros I
authors.initials: SI
authors.lastname: Dimitriadis
authors.affiliation: Digital Image and Signal Processing Laboratory, School of Electronic and Computer Engineering, Technical University of Crete, Chania 73100, Greece.
authors.forename: Michalis
authors.initials: M
authors.lastname: Zervakis
authors.affiliation: L. Widen Laboratory, School of Medicine, University of Crete, Greece.
authors.forename: Sifis
authors.initials: S
authors.lastname: Micheloyannis
authors.affiliation: Department of Pediatrics, Division of Clinical Neurosciences, University of Tennessee Health Science Center, Memphis, TN, USA; Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, TN, USA.
authors.forename: Roozbeh
authors.initials: R
authors.lastname: Rezaie
authors.affiliation: Department of Pediatrics, Division of Clinical Neurosciences, University of Tennessee Health Science Center, Memphis, TN, USA; Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, TN, USA; Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA.
authors.forename: Abbas
authors.initials: A
authors.lastname: Babajani-Feremi
authors.affiliation: Basque Center on Cognition, Brain and Language (BCBL), Paseo Mikeletegi 69, 20009 Donostia-San Sebastián, Spain; Biomedical Imaging Lab, Departments of Engineering Technology, Computer Science, Biomedical Engineering, and Electrical and Computer Engineering, University of Houston, Houston, TX 77204, USA.
authors.forename: George
authors.initials: G
authors.lastname: Zouridakis
authors.affiliation: Department of Pediatrics, Division of Clinical Neurosciences, University of Tennessee Health Science Center, Memphis, TN, USA; Neuroscience Institute, Le Bonheur Children's Hospital, Memphis, TN, USA; Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, USA.
authors.forename: Andrew C
authors.initials: AC
authors.lastname: Papanicolaou
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology*; D000070642:Brain Injuries, Traumatic / Q000503:physiopathology*; D001931:Brain Mapping; D058256:Brain Waves / Q000502:physiology*; D005260:Female; D023261:Glasgow Outcome Scale; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D012146:Rest; D055815:Young Adult
keywords: Biomarkers; Cross-frequency coupling; Magnetoencephalography (MEG); Mild traumatic brain injury; Tensors