title: Topologically Reorganized Connectivity Architecture of Default-Mode, Executive-Control, and Salience Networks across Working Memory Task Loads.
abstract: The human brain is topologically organized into a set of spatially distributed, functionally specific networks. Of these networks, the default-mode network (DMN), executive-control network (ECN), and salience network (SN) have received the most attention recently for their vital roles in cognitive functions. However, very little is known about whether and how the interactions within and between these 3 networks would be modulated by cognitive demands. Here, we employed graph-based modularity analysis to identify the DMN, ECN, and SN during an N-back working memory (WM) task and further investigated the modulation of intra- and inter-network interactions at different cognitive loads. As the task load elevated, functional connectivity decreased within the DMN while increased within the ECN, and the SN connected more with both the DMN and ECN. Within-network connectivity of the ventral and dorsal posterior cingulate cortex was differentially modulated by cognitive load. Further, the superior parietal regions in the ECN showed increased internetwork connections at higher WM loads, and these increases correlated positively with WM task performance. Together, these findings advance our understanding of dynamic integrations of specialized brain systems in response to cognitive demands and may serve as a baseline for assessing potential disruptions of these interactions in pathological conditions.
authors.affiliation: Neuroimaging Research Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA.|State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research.
authors.forename: Xia
authors.initials: X
authors.lastname: Liang
authors.affiliation: Center for MRI Research and Beijing City Key Lab for Medical Physics and Engineering, Peking University, Beijing 100871, China.
authors.forename: Qihong
authors.initials: Q
authors.lastname: Zou
authors.affiliation: State Key Laboratory of Cognitive Neuroscience and Learning and IDG/McGovern Institute for Brain Research.|Center for Collaboration and Innovation in Brain and Learning Sciences, Beijing Normal University, Beijing, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: He
authors.affiliation: Neuroimaging Research Branch, National Institute on Drug Abuse, National Institutes of Health, Baltimore, MD 21224, USA.
authors.forename: Yihong
authors.initials: Y
authors.lastname: Yang
mesh_terms: D000328:Adult; D001288:Attention / Q000502:physiology*; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods; D003071:Cognition / Q000502:physiology*; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009434:Neural Pathways / Q000502:physiology; D055815:Young Adult
keywords: connectomics; default-mode network; executive-control network; module; salience network