title: Dynamic functional network connectivity reveals unique and overlapping profiles of insula subdivisions.
abstract: The human insular cortex consists of functionally diverse subdivisions that engage during tasks ranging from interoception to cognitive control. The multiplicity of functions subserved by insular subdivisions calls for a nuanced investigation of their functional connectivity profiles. Four insula subdivisions (dorsal anterior, dAI; ventral, VI; posterior, PI; middle, MI) derived using a data-driven approach were subjected to static- and dynamic functional network connectivity (s-FNC and d-FNC) analyses. Static-FNC analyses replicated previous work demonstrating a cognition-emotion-interoception division of the insula, where the dAI is functionally connected to frontal areas, the VI to limbic areas, and the PI and MI to sensorimotor areas. Dynamic-FNC analyses consisted of k-means clustering of sliding windows to identify variable insula connectivity states. The d-FNC analysis revealed that the most frequently occurring dynamic state mirrored the cognition-emotion-interoception division observed from the s-FNC analysis, with less frequently occurring states showing overlapping and unique subdivision connectivity profiles. In two of the states, all subdivisions exhibited largely overlapping profiles, consisting of subcortical, sensory, motor, and frontal connections. Two other states showed the dAI exhibited a unique connectivity profile compared with other insula subdivisions. Additionally, the dAI exhibited the most variable functional connections across the s-FNC and d-FNC analyses, and was the only subdivision to exhibit dynamic functional connections with regions of the default mode network. These results highlight how a d-FNC approach can capture functional dynamics masked by s-FNC approaches, and reveal dynamic functional connections enabling the functional flexibility of the insula across time. Hum Brain Mapp 37:1770-1787, 2016. © 2016 Wiley Periodicals, Inc.
authors.affiliation: Department of Psychology, University of Miami, Coral Gables, Florida.
authors.forename: Jason S
authors.initials: JS
authors.lastname: Nomi
authors.affiliation: Department of Psychology, University of Miami, Coral Gables, Florida.
authors.forename: Kristafor
authors.initials: K
authors.lastname: Farrant
authors.affiliation: The Mind Research Network, Albuquerque, New Mexico.
authors.forename: Eswar
authors.initials: E
authors.lastname: Damaraju
authors.affiliation: The Mind Research Network, Albuquerque, New Mexico.
authors.forename: Srinivas
authors.initials: S
authors.lastname: Rachakonda
authors.affiliation: The Mind Research Network, Albuquerque, New Mexico.|Department of ECE, the University of New Mexico, Albuquerque, New Mexico.
authors.forename: Vince D
authors.initials: VD
authors.lastname: Calhoun
authors.affiliation: Department of Psychology, University of Miami, Coral Gables, Florida.|University of Miami Miller School of Medicine, Neuroscience Program, Miami, Florida.
authors.forename: Lucina Q
authors.initials: LQ
authors.lastname: Uddin
mesh_terms: D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008959:Models, Neurological; D009415:Nerve Net / Q000000981:diagnostic imaging*; D009434:Neural Pathways / Q000000981:diagnostic imaging*; D059906:Neuroimaging; D017711:Nonlinear Dynamics; D055815:Young Adult
keywords: default mode network; dynamic functional network connectivity; flexibility; insular cortex; limbic system; resting state fMRI; salience network