title: Disrupted Structural and Functional Connectivity in Prefrontal-Hippocampus Circuitry in First-Episode Medication-Naïve Adolescent Depression.
abstract: BACKGROUND
  Evidence implicates abnormalities in prefrontal-hippocampus neural circuitry in major depressive disorder (MDD). This study investigates the potential disruptions in prefrontal-hippocampus structural and functional connectivity, as well as their relationship in first-episode medication-naïve adolescents with MDD in order to investigate the early stage of the illness without confounds of illness course and medication exposure.
  
  
  METHODS
  Diffusion tensor imaging and resting-state functional magnetic resonance imaging (rs-fMRI) data were acquired from 26 first-episode medication-naïve MDD adolescents and 31 healthy controls (HC). Fractional anisotropy (FA) values of the fornix and the prefrontal-hippocampus functional connectivity was compared between MDD and HC groups. The correlation between the FA value of fornix and the strength of the functional connectivity in the prefrontal cortex (PFC) region showing significant differences between the two groups was identified.
  
  
  RESULTS
  Compared with the HC group, adolescent MDD group had significant lower FA values in the fornix, as well as decreased functional connectivity in four PFC regions. Significant negative correlations were observed between fornix FA values and functional connectivity from hippocampus to PFC within the HC group. There was no significant correlation between the fornix FA and the strength of functional connectivity within the adolescent MDD group.
  
  
  CONCLUSIONS
  First-episode medication-naïve adolescent MDD showed decreased structural and functional connectivity as well as deficits of the association between structural and functional connectivity shown in HC in the PFC-hippocampus neural circuitry. These findings suggest that abnormal PFC-hippocampus neural circuitry may present in the early onset of MDD and play an important role in the neuropathophysiology of MDD.
authors: Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.
authors: Haiyang
authors: H
authors: Geng
authors: Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.
authors: Feng
authors: F
authors: Wu
authors: Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.
authors: Lingtao
authors: L
authors: Kong
authors: Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.|Department of Gerontology, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.
authors: Yanqing
authors: Y
authors: Tang
authors: Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.
authors: Qian
authors: Q
authors: Zhou
authors: Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.
authors: Miao
authors: M
authors: Chang
authors: Department of Gerontology, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.
authors: Yifang
authors: Y
authors: Zhou
authors: Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.
authors: Xiaowei
authors: X
authors: Jiang
authors: Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.
authors: Songbai
authors: S
authors: Li
authors: Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.|Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning, PR China.|Department of Psychiatry, Yale University School of Medicine, New Haven, CT, 06511, United States of America.
authors: Fei
authors: F
authors: Wang
mesh_terms: D000293:Adolescent; D016880:Anisotropy; D016022:Case-Control Studies; D063132:Connectome; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000473:pathology / Q000503:physiopathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006624:Hippocampus / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D017397:Prefrontal Cortex / Q000473:pathology / Q000503:physiopathology*; D011569:Psychiatric Status Rating Scales