title: Amygdala connectivity differs among chronic, early course, and individuals at risk for developing schizophrenia.
abstract: Alterations in circuits involving the amygdala have been repeatedly implicated in schizophrenia neuropathology, given their role in stress, affective salience processing, and psychosis onset. Disturbances in amygdala whole-brain functional connectivity associated with schizophrenia have yet to be fully characterized despite their importance in psychosis. Moreover, it remains unknown if there are functional alterations in amygdala circuits across illness phases. To evaluate this possibility, we compared whole-brain amygdala connectivity in healthy comparison subjects (HCS), individuals at high risk (HR) for schizophrenia, individuals in the early course of schizophrenia (EC-SCZ), and patients with chronic schizophrenia (C-SCZ). We computed whole-brain resting-state connectivity using functional magnetic resonance imaging at 3T via anatomically defined individual-specific amygdala seeds. We identified significant alterations in amygdala connectivity with orbitofrontal cortex (OFC), driven by reductions in EC-SCZ and C-SCZ (effect sizes of 1.0 and 0.97, respectively), but not in HR for schizophrenia, relative to HCS. Reduced amygdala-OFC coupling was associated with schizophrenia symptom severity (r = .32, P < .015). Conversely, we identified a robust increase in amygdala connectivity with a brainstem region around noradrenergic arousal nuclei, particularly for HR individuals relative to HCS (effect size = 1.54), but not as prominently for other clinical groups. These results suggest that deficits in amygdala-OFC coupling could emerge during the initial episode of schizophrenia (EC-SCZ) and may present as an enduring feature of the illness (C-SCZ) in association with symptom severity but are not present in individuals with elevated risk for developing schizophrenia. Instead, in HR individuals, there appears to be increased connectivity in a circuit implicated in stress response.
authors.forename: Alan
authors.initials: A
authors.lastname: Anticevic
authors.affiliation: Department of Psychiatry, The First Affiliated Hospital, China Medical University, Shenyang , Liaoning, PR China;
authors.forename: Yanqing
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Department of Psychiatry, Yale University School of Medicine, New Haven, CT;
authors.forename: Youngsun T
authors.initials: YT
authors.lastname: Cho
authors.affiliation: Department of Psychology, University of Ljubljana, Ljubljana, Slovenia;
authors.forename: Grega
authors.initials: G
authors.lastname: Repovs
authors.affiliation: Department of Psychology, Washington University in St Louis, St Louis, MO;
authors.forename: Michael W
authors.initials: MW
authors.lastname: Cole
authors.affiliation: Department of Psychiatry, Yale University School of Medicine, New Haven, CT; University Psychiatric Hospital Vrapce, University of Zagreb, Zagreb, Croatia;
authors.forename: Aleksandar
authors.initials: A
authors.lastname: Savic
authors.affiliation: Department of Psychiatry, Yale University School of Medicine, New Haven, CT; Department of Radiology, The First Affiliated Hospital, China Medical University, Shenyang , Liaoning, PR China.
authors.forename: Fei
authors.initials: F
authors.lastname: Wang
authors.forename: John H
authors.initials: JH
authors.lastname: Krystal
authors.affiliation: Department of Radiology, The First Affiliated Hospital, China Medical University, Shenyang , Liaoning, PR China kexu@vip.sina.com.
authors.forename: Ke
authors.initials: K
authors.lastname: Xu
mesh_terms: D000328:Adult; D000679:Amygdala / Q000503:physiopathology*; D001933:Brain Stem / Q000503:physiopathology*; D002908:Chronic Disease; D063132:Connectome; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000503:physiopathology; D017397:Prefrontal Cortex / Q000503:physiopathology*; D062706:Prodromal Symptoms; D012306:Risk; D012559:Schizophrenia / Q000503:physiopathology*; D055815:Young Adult
keywords: amygdala; connectivity; first episode; prefrontal cortex; risk for schizophrenia; schizophrenia