TY - JOUR T1 - Dynamic Functional Connectivity between Order and Randomness and its Evolution across the Human Adult Lifespan JF - bioRxiv DO - 10.1101/107243 SP - 107243 AU - Demian Battaglia AU - Thomas Boudou AU - Enrique C. A. Hansen AU - Diego Lombardo AU - Sabrina Chettouf AU - Andreas Daffertshofer AU - Anthony R. McIntosh AU - Joelle Zimmermann AU - Petra Ritter AU - Viktor Jirsa Y1 - 2020/01/01 UR - http://biorxiv.org/content/early/2020/01/17/107243.abstract N2 - Functional Connectivity (FC) in resting-state or task conditions is not frozen but inherently dynamic. Yet, there is no consensus on whether fluctuations in FC resemble isolated transitions between discrete FC states rather than continuous changes. This quarrel hampered advancing the study of dynamic FC. This is unfortunate as the structure of fluctuations in FC can provide crucial information about developmental changes, aging, or progression of pathologies. We merge the two perspectives and consider dynamic FC as continuous network reconfiguration, including a stochastic exploration of the space of possible steady FC states. The statistical properties of this random walk deviate both from an “order-driven” dynamics, in which the mean FC is preserved, and from a “randomness-driven” scenario, in which fluctuations of FC remain uncorrelated over time. Instead, dynamic FC turns out to have a complex structure endowed with long-range sequential correlations giving rise to transient slowing and acceleration epochs in the continuous flow of reconfiguration. When applying our analysis to an fMRI dataset in healthy elderly, we find that the dynamic FC tends to slow down, becomes less complex and more random with increasing age. All these effects are strongly associated with age-related changes in cognitive performance.HighlightsDynamic Functional Connectivity (dFC) at rest and during cognitive task performs a “complex” (anomalous) random walk.Speed of dFC slows down with aging.Resting dFC replaces complexity by randomness with aging.Task performance correlates with the speed and complexity of dFC.rsresting-stateRSNresting-state networkfMRIfunctional magnetic resonance imagingBOLDblood oxygen level dependentSCstructural connectivityFCfunctional connectivitydFCdynamic functional connectivityDFAdetrended fluctuation analysisMoCAMontreal Cognitive AssessmentSOspectral overlap ER -