title: Default-Mode Network Abnormalities in Pediatric Posttraumatic Stress Disorder.
abstract: OBJECTIVE
  Resting-state functional magnetic resonance imaging (rs-fMRI) studies of adult posttraumatic stress disorder (PTSD) have identified default-mode network (DMN) abnormalities, including reduced within-network connectivity and reduced anticorrelation between the DMN and task-positive network (TPN). However, no prior studies have specifically examined DMN connectivity in pediatric PTSD, which may differ due to neurodevelopmental factors.
  
  
  METHODS
  A total of 29 youth with PTSD and 30 nontraumatized healthy youth of comparable age and sex completed rs-fMRI. DMN properties were examined using posterior cingulate cortex (PCC) seed-based connectivity and independent component analysis (ICA).
  
  
  RESULTS
  Contrary to findings in adult studies, youth with PTSD displayed increased connectivity within the DMN, including increased PCC-inferior parietal gyrus connectivity, and age-related increases in PCC-ventromedial prefrontal cortex connectivity. Strikingly, youth with PTSD also displayed greater anticorrelation between the PCC and multiple nodes within salience and attentional control networks of the TPN. ICA revealed greater anticorrelation between the entire DMN and TPN networks in youth with PTSD. Furthermore, DMN and TPN connectivity strength were positively and negatively associated, respectively, with re-experiencing symptoms of PTSD.
  
  
  CONCLUSIONS
  Pediatric PTSD is characterized by heightened within-DMN connectivity, which may contribute to re-experiencing symptoms of PTSD and is consistent with the role of the DMN in autobiographical memory. At the same time, greater anticorrelation between the DMN and attentional control networks may represent compensatory mechanisms aimed at suppressing trauma-related thought, a notion supported by the inverse relationship between TPN strength and re-experiencing. These findings provide new insights into large-scale network abnormalities underlying pediatric PTSD, which could serve as biomarkers of illness and treatment response.
authors.affiliation: University of Wisconsin-Madison; University of Minnesota, Minneapolis.
authors.forename: Rémi
authors.initials: R
authors.lastname: Patriat
authors.affiliation: University of Wisconsin-Madison; University of Wisconsin School of Medicine and Public Health, Madison.
authors.forename: Rasmus M
authors.initials: RM
authors.lastname: Birn
authors.affiliation: University of Wisconsin School of Medicine and Public Health, Madison.
authors.forename: Taylor J
authors.initials: TJ
authors.lastname: Keding
authors.affiliation: University of Wisconsin School of Medicine and Public Health, Madison. Electronic address: herringa@wisc.edu.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Herringa
mesh_terms: D000293:Adolescent; D001921:Brain / Q000000981:diagnostic imaging / Q000503:physiopathology; D001931:Brain Mapping; D016022:Case-Control Studies; D002648:Child; D063132:Connectome / Q000523:psychology; D005260:Female; D006179:Gyrus Cinguli / Q000000981:diagnostic imaging / Q000503:physiopathology; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008564:Membrane Potentials / Q000502:physiology; D009415:Nerve Net / Q000000981:diagnostic imaging / Q000503:physiopathology; D009434:Neural Pathways / Q000503:physiopathology; D010296:Parietal Lobe / Q000503:physiopathology; D017397:Prefrontal Cortex / Q000503:physiopathology; D013313:Stress Disorders, Post-Traumatic / Q000000981:diagnostic imaging* / Q000503:physiopathology*
keywords: DMN; connectivity; pediatric PTSD; rs-fMRI