title: Developmental Changes in Brain Network Hub Connectivity in Late Adolescence.
abstract: The human brain undergoes substantial development throughout adolescence and into early adulthood. This maturational process is thought to include the refinement of connectivity between putative connectivity hub regions of the brain, which collectively form a dense core that enhances the functional integration of anatomically distributed, and functionally specialized, neural systems. Here, we used longitudinal diffusion magnetic resonance imaging to characterize changes in connectivity between 80 cortical and subcortical anatomical regions over a 2 year period in 31 adolescents between the ages of 15 and 19 years. Connectome-wide analysis indicated that only a small subset of connections showed evidence of statistically significant developmental change over the study period, with 8% and 6% of connections demonstrating decreased and increased structural connectivity, respectively. Nonetheless, these connections linked 93% and 90% of the 80 regions, respectively, pointing to a selective, yet anatomically distributed pattern of developmental changes that involves most of the brain. Hub regions showed a distinct tendency to be highly connected to each other, indicating robust "rich-club" organization. Moreover, connectivity between hubs was disproportionately influenced by development, such that connectivity between subcortical hubs decreased over time, whereas frontal-subcortical and frontal-parietal hub-hub connectivity increased over time. These findings suggest that late adolescence is characterized by selective, yet significant remodeling of hub-hub connectivity, with the topological organization of hubs shifting emphasis from subcortical hubs in favor of an increasingly prominent role for frontal hub regions.
authors.affiliation: Turning Point, Eastern Health and Eastern Health Clinical School, Monash University, Victoria 3065, Australia, Monash Clinical and Imaging Neuroscience, School of Psychological Sciences and Monash Biomedical Imaging, Monash University, Victoria 3168, Australia, Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Victoria 3053, Australia.
authors.forename: Simon T E
authors.initials: ST
authors.lastname: Baker
authors.affiliation: Turning Point, Eastern Health and Eastern Health Clinical School, Monash University, Victoria 3065, Australia.
authors.forename: Dan I
authors.initials: DI
authors.lastname: Lubman
authors.affiliation: Monash Clinical and Imaging Neuroscience, School of Psychological Sciences and Monash Biomedical Imaging, Monash University, Victoria 3168, Australia, Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Victoria 3053, Australia.
authors.forename: Murat
authors.initials: M
authors.lastname: Yücel
authors.affiliation: Melbourne School of Psychological Sciences, Orygen Youth Health Research Centre, Centre for Youth Mental Health, and.
authors.forename: Nicholas B
authors.initials: NB
authors.lastname: Allen
authors.affiliation: Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Victoria 3053, Australia.
authors.forename: Sarah
authors.initials: S
authors.lastname: Whittle
authors.affiliation: Monash Clinical and Imaging Neuroscience, School of Psychological Sciences and Monash Biomedical Imaging, Monash University, Victoria 3168, Australia.
authors.forename: Ben D
authors.identifier: http://orcid.org/0000-0002-3003-4055
authors.initials: BD
authors.lastname: Fulcher
authors.affiliation: Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Victoria 3053, Australia, Melbourne School of Engineering, The University of Melbourne, Victoria 3010, Australia.
authors.forename: Andrew
authors.initials: A
authors.lastname: Zalesky
authors.affiliation: Monash Clinical and Imaging Neuroscience, School of Psychological Sciences and Monash Biomedical Imaging, Monash University, Victoria 3168, Australia, Melbourne Neuropsychiatry Centre, Department of Psychiatry, The University of Melbourne and Melbourne Health, Victoria 3053, Australia, alex.fornito@monash.edu.
authors.forename: Alex
authors.initials: A
authors.lastname: Fornito
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001921:Brain / Q000254:growth & development*; D001931:Brain Mapping / Q000379:methods; D063132:Connectome / Q000379:methods*; D056324:Diffusion Tensor Imaging / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D009415:Nerve Net / Q000254:growth & development*; D009434:Neural Pathways / Q000254:growth & development; D055815:Young Adult
keywords: MRI; adolescence; connectome; development; graph theory; structural connectivity