title: Dynamic network participation of functional connectivity hubs assessed by resting-state fMRI.
abstract: Network studies of large-scale brain connectivity have demonstrated that highly connected areas, or "hubs," are a key feature of human functional and structural brain organization. We use resting-state functional MRI data and connectivity clustering to identify multi-network hubs and show that while hubs can belong to multiple networks their degree of integration into these different networks varies dynamically over time. The extent of the network variation was related to the connectedness of the hub. In addition, we found that these network dynamics were inversely related to positive self-generated thoughts reported by individuals and were further decreased with older age. Moreover, the left caudate varied its degree of participation between a default mode subnetwork and a limbic network. This variation was predictive of individual differences in the reports of past-related thoughts. These results support an association between ongoing thought processes and network dynamics and offer a new approach to investigate the brain dynamics underlying mental experience.
authors.affiliation: Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Schaefer
authors.affiliation: Max Planck Research Group for Neuroanatomy & Connectivity, Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Margulies
authors.affiliation: Department of High-field Magnetic Resonance, Max Planck Institute for Biological Cybernetics Tübingen, Germany.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Lohmann
authors.affiliation: Max Planck Research Group for Neuroanatomy & Connectivity, Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany.
authors.forename: Krzysztof J
authors.initials: KJ
authors.lastname: Gorgolewski
authors.affiliation: Department of Psychology, The University of York Hesslington, UK.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Smallwood
authors.affiliation: Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany ; Department of Neurology, Biomagnetic Center, University Clinics Jena Jena, Germany.
authors.forename: Stefan J
authors.initials: SJ
authors.lastname: Kiebel
authors.affiliation: Department of Neurology, Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany ; Berlin School of Mind and Brain, Mind and Brain Institute Berlin, Germany ; Department of Cognitive Neurology, University Hospital Leipzig Leipzig, Germany ; Center for Stroke Research, Charité - Universitätsmedizin Berlin, Germany.
authors.forename: Arno
authors.initials: A
authors.lastname: Villringer
keywords: brain networks; graphs; mind wandering; self-generated thoughts