title: Large-scale functional network reorganization in 22q11.2 deletion syndrome revealed by modularity analysis.
abstract: The 22q11.2 deletion syndrome (22q11DS) is associated with cognitive impairments and a 41% risk of developing schizophrenia. While several studies performed on patients with 22q11DS showed the presence of abnormal functional connectivity in this syndrome, how these alterations affect large-scale network organization is still unknown. Here we performed a network modularity analysis on whole-brain functional connectomes derived from the resting-state fMRI of 40 patients with 22q11DS and 41 healthy control participants, aged between 9 and 30 years old. We then split the sample at 18 years old to obtain two age subgroups and repeated the modularity analyses. We found alterations of modular communities affecting the visuo-spatial network and the anterior cingulate cortex (ACC) in both age groups. These results corroborate previous structural and functional studies in 22q11DS that showed early impairment of visuo-spatial processing regions. Furthermore, as ACC has been linked to the development of psychotic symptoms in 22q11DS, the early impairment of its functional connectivity provide further support that ACC alterations may provide potential biomarkers for an increased risk of schizophrenia. Finally, we found an abnormal modularity partition of the dorsolateral prefrontal cortex (DLPFC) only in adults with 22q11DS, suggesting the presence of an abnormal development of functional network communities during adolescence in 22q11DS.
authors.affiliation: Office Médico-Pédagogique Research Unit, Department of Psychiatry, University of Geneva School of Medicine, Geneva 8, Switzerland. Electronic address: elisa.scariati@unige.ch.
authors.forename: Elisa
authors.initials: E
authors.lastname: Scariati
authors.affiliation: Stanford Cognitive and Systems Neuroscience Laboratory, Stanford University School of Medicine, Palo Alto, CA, USA.
authors.forename: Marie
authors.initials: M
authors.lastname: Schaer
authors.affiliation: Office Médico-Pédagogique Research Unit, Department of Psychiatry, University of Geneva School of Medicine, Geneva 8, Switzerland; Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, USA; Medical Image Processing Lab, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
authors.forename: Isik
authors.initials: I
authors.lastname: Karahanoglu
authors.affiliation: Office Médico-Pédagogique Research Unit, Department of Psychiatry, University of Geneva School of Medicine, Geneva 8, Switzerland.
authors.forename: Maude
authors.initials: M
authors.lastname: Schneider
authors.affiliation: Laboratory for Neurology and imaging of Cognition, Department of Fundamental Neurosciences, University of Geneva, Switzerland.
authors.forename: Jonas
authors.initials: J
authors.lastname: Richiardi
authors.affiliation: Office Médico-Pédagogique Research Unit, Department of Psychiatry, University of Geneva School of Medicine, Geneva 8, Switzerland; Adolescence Clinical Psychology Research Unit, Faculty of Psychology and Educational Sciences, University of Geneva, Geneva, Switzerland.
authors.forename: Martin
authors.initials: M
authors.lastname: Debbané
authors.affiliation: Department of Radiology and Medical Informatics, University of Geneva, Geneva, Switzerland; Medical Image Processing Lab, Institute of Bioengineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland.
authors.forename: Dimitri
authors.initials: D
authors.lastname: Van De Ville
authors.affiliation: Office Médico-Pédagogique Research Unit, Department of Psychiatry, University of Geneva School of Medicine, Geneva 8, Switzerland; Department of Genetic Medicine and Development, University of Geneva School of Medicine, Geneva, Switzerland.
authors.forename: Stephan
authors.initials: S
authors.lastname: Eliez
mesh_terms: D000293:Adolescent; D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging* / Q000503:physiopathology; D002648:Child; D063132:Connectome; D004062:DiGeorge Syndrome / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000000981:diagnostic imaging* / Q000503:physiopathology; D009434:Neural Pathways / Q000000981:diagnostic imaging / Q000503:physiopathology; D013028:Space Perception / Q000502:physiology; D014796:Visual Perception / Q000502:physiology; D055815:Young Adult
keywords: Brain development; Connectome; Graph theory; Modularity; Resting-state fMRI; Schizophrenia