Dynamic functional connectivity reveals altered variability in functional connectivity among patients with major depressive disorder.
Resting-state fMRI (RS-fMRI) has become a useful tool to investigate the connectivity structure of mental health disorders. In the case of major depressive disorder (MDD), recent studies regarding the RS-fMRI have found abnormal connectivity in several regions of the brain, particularly in the default mode network (DMN). Thus, the relevance of the DMN to self-referential thoughts and ruminations has made the use of the resting-state approach particularly important for MDD. The majority of such research has relied on the grand averaged functional connectivity measures based on the temporal correlations between the BOLD time series of various brain regions. We, in our study, investigated the variations in the functional connectivity over time at global and local level using RS-fMRI BOLD time series of 27 MDD patients and 27 healthy control subjects. We found that global synchronization and temporal stability were significantly increased in the MDD patients. Furthermore, the participants with MDD showed significantly increased overall average (static) functional connectivity (sFC) but decreased variability of functional connectivity (vFC) within specific networks. Static FC increased to predominance among the regions pertaining to the default mode network (DMN), while the decreased variability of FC was observed in the connections between the DMN and the frontoparietal network. Hum Brain Mapp 37:2918-2930, 2016. © 2016 Wiley Periodicals, Inc.
Department of Information and Communication Technologies, Center for Brain and Cognition, Universitat Pompeu Fabra, Barcelona, Spain.
Murat
M
Demirtaş
Department of Information and Communication Technologies, Center for Brain and Cognition, Universitat Pompeu Fabra, Barcelona, Spain.
Cristian
C
Tornador
BarcelonaBeta Brain Research Center, Pasqual Maragall Foundation, Barcelona, Spain.|CIBER-BBN, Barcelona, Spain.
Carles
C
Falcón
Department of Psychology and Neuroscience, University of Colorado, Boulder, Colorado.|MRI Research Unit, CRC Mar, Hospital del Mar, Barcelona, Spain.
Marina
M
López-Solà
Carlos III Health Institute, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain.|Psychiatry Department, Bellvitge University Hospital, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain.
Rosa
R
Hernández-Ribas
Department of Radiology, MRI Research Unit, Hospital del Mar, Barcelona, Spain.
Jesús
J
Pujol
Carlos III Health Institute, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain.|Psychiatry Department, Bellvitge University Hospital, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain.|Department of Clinical Sciences, University of Barcelona, Barcelona, Spain.
José M
JM
Menchón
Max-Planck Institute for Cognitive and Brain Sciences, Leipzig, Germany.|Department of Neurology, Charité, Berlin, Germany.
Petra
P
Ritter
Mental Health Department, Depression and Anxiety Program, Parc Taulí Sabadell, Barcelona, Spain.|Hospital Universitari Department of Psychiatry and Legal Medicine, Universitat Autònoma De Barcelona, Spain.
Narcis
N
Cardoner
Carlos III Health Institute, Centro de Investigación Biomédica en Red de Salud Mental (CIBERSAM), Spain.|Psychiatry Department, Bellvitge University Hospital, Bellvitge Biomedical Research Institute (IDIBELL), Barcelona, Spain.|Department of Psychobiology and Methodology of Health Sciences, Universitat Autònoma De Barcelona, Spain.
Carles
C
Soriano-Mas
Department of Information and Communication Technologies, Center for Brain and Cognition, Universitat Pompeu Fabra, Barcelona, Spain.|Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain.
Gustavo
G
Deco
D000328:Adult; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D003865:Major Depressive Disorder / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D009434:Neural Pathways / Q000503:physiopathology*; D012146:Rest / Q000502:physiology
dynamic functional connectivity; fMRI; major depressive disorder; mood disorders; resting state