title: Functional Connectivity Hubs and Networks in the Awake Marmoset Brain.
abstract: In combination with advances in analytical methods, resting-state fMRI is allowing unprecedented access to a better understanding of the network organization of the brain. Increasing evidence suggests that this architecture may incorporate highly functionally connected nodes, or "hubs", and we have recently proposed local functional connectivity density (lFCD) mapping to identify highly-connected nodes in the human brain. Here, we imaged awake nonhuman primates to test whether, like the human brain, the marmoset brain contains FC hubs. Ten adult common marmosets (Callithrix jacchus) were acclimated to mild, comfortable restraint using individualized helmets. Following restraint training, resting BOLD data were acquired during eight consecutive 10 min scans for each subject. lFCD revealed prominent cortical and subcortical hubs of connectivity across the marmoset brain; specifically, in primary and secondary visual cortices (V1/V2), higher-order visual association areas (A19M/V6[DM]), posterior parietal and posterior cingulate areas (PGM and A23b/A31), thalamus, dorsal and ventral striatal areas (caudate, putamen, lateral septal nucleus, and anterior cingulate cortex (A24a). lFCD hubs were highly connected to widespread areas of the brain, and further revealed significant network-network interactions. These data provide a baseline platform for future investigations in a nonhuman primate model of the brain's network topology.
authors.affiliation: Department of Psychiatry, University of Maryland School of MedicineBaltimore, MD, USA; National Institute on Drug Abuse, National Institutes of HealthBaltimore, MD, USA.
authors.forename: Annabelle M
authors.initials: AM
authors.lastname: Belcher
authors.affiliation: National Institute of Neurological Disorders and Stroke, National Institutes of Health Bethesda, MD, USA.
authors.forename: Cecil Chern-Chyi
authors.initials: CC
authors.lastname: Yen
authors.affiliation: National Institute of Neurological Disorders and Stroke, National Institutes of Health Bethesda, MD, USA.
authors.forename: Lucia
authors.initials: L
authors.lastname: Notardonato
authors.affiliation: National Institute on Drug Abuse, National Institutes of Health Baltimore, MD, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Ross
authors.affiliation: National Institute on Drug Abuse, National Institutes of HealthRockville, MD, USA; National Institute on Alcohol Abuse and Alcoholism, National Institutes of HealthBethesda, MD, USA.
authors.forename: Nora D
authors.initials: ND
authors.lastname: Volkow
authors.affiliation: National Institute on Drug Abuse, National Institutes of Health Baltimore, MD, USA.
authors.forename: Yihong
authors.initials: Y
authors.lastname: Yang
authors.affiliation: National Institute on Drug Abuse, National Institutes of Health Baltimore, MD, USA.
authors.forename: Elliot A
authors.initials: EA
authors.lastname: Stein
authors.affiliation: National Institute of Neurological Disorders and Stroke, National Institutes of Health Bethesda, MD, USA.
authors.forename: Afonso C
authors.initials: AC
authors.lastname: Silva
authors.affiliation: National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health Bethesda, MD, USA.
authors.forename: Dardo
authors.initials: D
authors.lastname: Tomasi
keywords: functional connectivity; hubs; resting-state fMRI; resting-state networks