Fundamental dynamical modes underlying human brain synchronization.
Little is known about the long-term dynamics of widely interacting cortical and subcortical networks during the wake-sleep cycle. Using large-scale intracranial recordings of epileptic patients during seizure-free periods, we investigated local- and long-range synchronization between multiple brain regions over several days. For such high-dimensional data, summary information is required for understanding and modelling the underlying dynamics. Here, we suggest that a compact yet useful representation is given by a state space based on the first principal components. Using this representation, we report, with a remarkable similarity across the patients with different locations of electrode placement, that the seemingly complex patterns of brain synchrony during the wake-sleep cycle can be represented by a small number of characteristic dynamic modes. In this space, transitions between behavioral states occur through specific trajectories from one mode to another. These findings suggest that, at a coarse level of temporal resolution, the different brain states are correlated with several dominant synchrony patterns which are successively activated across wake-sleep states.
Centre de Recherche de l'Institut du Cerveau et de la Moelle Épinière, INSERM, UMRS 975 and CNRS UMR 7225, UPMC, Hôpital de la Pitié-Salpêtrière, 75651 Paris cedex 13, France.
Catalina
C
Alvarado-Rojas
Michel
M
Le Van Quyen
D000465:Algorithms; D001331:Automation; D001921:Brain / Q000502:physiology*; D016000:Cluster Analysis; D004569:Electroencephalography / Q000379:methods*; D004828:Epilepsies, Partial / Q000503:physiopathology; D006801:Humans; D008962:Models, Theoretical; D008991:Monitoring, Physiologic / Q000379:methods; D009991:Oscillometry / Q000379:methods; D025341:Principal Component Analysis; D015203:Reproducibility of Results; D012815:Signal Processing, Computer-Assisted