title: Individual-specific features of brain systems identified with resting state functional correlations.
abstract: Recent work has made important advances in describing the large-scale systems-level organization of human cortex by analyzing functional magnetic resonance imaging (fMRI) data averaged across groups of subjects. However, new findings have emerged suggesting that individuals' cortical systems are topologically complex, containing small but reliable features that cannot be observed in group-averaged datasets, due in part to variability in the position of such features along the cortical sheet. This previous work has reported only specific examples of these individual-specific system features; to date, such features have not been comprehensively described. Here we used fMRI to identify cortical system features in individual subjects within three large cross-subject datasets and one highly sampled within-subject dataset. We observed system features that have not been previously characterized, but 1) were reliably detected across many scanning sessions within a single individual, and 2) could be matched across many individuals. In total, we identified forty-three system features that did not match group-average systems, but that replicated across three independent datasets. We described the size and spatial distribution of each non-group feature. We further observed that some individuals were missing specific system features, suggesting individual differences in the system membership of cortical regions. Finally, we found that individual-specific system features could be used to increase subject-to-subject similarity. Together, this work identifies individual-specific features of human brain systems, thus providing a catalog of previously unobserved brain system features and laying the foundation for detailed examinations of brain connectivity in individuals.
authors.affiliation: VISN 17 Center of Excellence for Research on Returning War Veterans, Waco, TX, USA; Departments of Neurology, Washington University School of Medicine, St. Louis, MO, USA; Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA. Electronic address: evan.gordon@gmail.com.
authors.forename: Evan M
authors.initials: EM
authors.lastname: Gordon
authors.affiliation: Departments of Neurology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Timothy O
authors.initials: TO
authors.lastname: Laumann
authors.affiliation: Departments of Neurology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Babatunde
authors.initials: B
authors.lastname: Adeyemo
authors.affiliation: Departments of Psychological and Brain Sciences, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Adrian W
authors.initials: AW
authors.lastname: Gilmore
authors.affiliation: VISN 17 Center of Excellence for Research on Returning War Veterans, Waco, TX, USA; Center for Vital Longevity, School of Behavioral and Brain Sciences, University of Texas at Dallas, Dallas, TX, USA.
authors.forename: Steven M
authors.initials: SM
authors.lastname: Nelson
authors.affiliation: Departments of Neurology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Nico U F
authors.initials: NUF
authors.lastname: Dosenbach
authors.affiliation: Departments of Neurology, Washington University School of Medicine, St. Louis, MO, USA; Departments of Psychological and Brain Sciences, Washington University School of Medicine, St. Louis, MO, USA; Departments of Radiology, Washington University School of Medicine, St. Louis, MO, USA; Departments of Anatomy and Neurobiology, Washington University School of Medicine, St. Louis, MO, USA.
authors.forename: Steven E
authors.initials: SE
authors.lastname: Petersen
mesh_terms: D000328:Adult; D002540:Cerebral Cortex / Q000502:physiology*; D063132:Connectome; D005260:Female; D006801:Humans; D007206:Individuality; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000502:physiology; D055815:Young Adult
keywords: Brain systems; Functional connectivity; Individual variability; fMRI