title: Distinguishing bipolar and major depressive disorders by brain structural morphometry: a pilot study.
abstract: BACKGROUND
  The clinical presentation of common symptoms during depressive episodes in bipolar disorder (BD) and major depressive disorder (MDD) poses challenges for accurate diagnosis. Disorder-specific neuroanatomical features may aid the development of reliable discrimination between these two clinical conditions.
  
  
  METHODS
  For our sample of 16 BD patients, 19 MDD patients and 29 healthy volunteers, we adopted vertex-wise cortical based brain imaging techniques to examine cortical thickness and surface area, two components of cortical volume with distinct genetic determinants. Based on specific characteristics of neuroanatomical features, we then used support vector machine (SVM) algorithm to discriminate between patients with BD and MDD.
  
  
  RESULTS
  Compared to MDD patients, BD patients showed significantly larger cortical surface area in the left bankssts, precuneus, precentral, inferior parietal, superior parietal and the right middle temporal gyri. In addition, larger volumes of subcortical regions were found in BD patients. In SVM discriminative analyses, the overall accuracy was 74.3 %, with a sensitivity of 62.5 % and a specificity of 84.2 % (p = 0.028). Compared to controls, larger surface area in the temporo-parietal regions were observed in BD patients, and thinner cortices in fronto-temporal regions were observed in MDD patients, especially in the medial orbito-frontal area.
  
  
  CONCLUSIONS
  These findings have demonstrated distinct spatially distributed variations in cortical thickness and surface area in patients with BD and MDD, suggesting potentially varying etiological and neuropathological processes in these two conditions. The employment of multimodal classification on disorder-specific biological features has shed light to the development of potential classification tools that could aid diagnostic decisions.
authors.affiliation: Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China. germainefung@gmail.com.|Department of Psychology, the Chinese University of Hong Kong, Hong Kong Special Administrative Region, China. germainefung@gmail.com.
authors.forename: Germaine
authors.initials: G
authors.lastname: Fung
authors.affiliation: Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China. michelle23deng@gmail.com.|Cognitive Analysis & Brain Imaging Laboratory, MIND Institute, University of California, Davis, USA. michelle23deng@gmail.com.
authors.forename: Yi
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China. qing.zhao5@griffithuni.edu.au.|School of Applied Psychology and Behavioral Basis of Health Program, Griffith Health Institute, Griffith University, Brisbane, Australia. qing.zhao5@griffithuni.edu.au.
authors.forename: Qing
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China. moonlightforever@126.com.|University of Chinese Academy of Sciences, Beijing, China. moonlightforever@126.com.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Encephalopathy, Beijing University of Chinese Medicine the 3rd Affiliated Hospital, Beijing, China. qumiaotcm@yahoo.com.cn.
authors.forename: Miao
authors.initials: M
authors.lastname: Qu
authors.affiliation: MRI Center of Beijing 306 Hospital, Beijing, China. leeker1974@126.com.
authors.forename: Ke
authors.initials: K
authors.lastname: Li
authors.affiliation: MRI Center of Beijing 306 Hospital, Beijing, China. zyw_306@sina.com.
authors.forename: Ya-Wei
authors.initials: YW
authors.lastname: Zeng
authors.affiliation: MRI Center of Beijing 306 Hospital, Beijing, China. mdjinzhen@163.com.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Jin
authors.affiliation: Peking University Sixth Hospital, Beijing, China. mayantao@bjmu.edu.cn.|Peking University Institute of Mental Health, Beijing, China. mayantao@bjmu.edu.cn.|Key Laboratory of Mental Health, Ministry of Health (Peking University), Beijing, China. mayantao@bjmu.edu.cn.
authors.forename: Yan-Tao
authors.initials: YT
authors.lastname: Ma
authors.affiliation: Peking University Sixth Hospital, Beijing, China. yuxin@bjmu.edu.cn.|Peking University Institute of Mental Health, Beijing, China. yuxin@bjmu.edu.cn.|Key Laboratory of Mental Health, Ministry of Health (Peking University), Beijing, China. yuxin@bjmu.edu.cn.
authors.forename: Xin
authors.initials: X
authors.lastname: Yu
authors.affiliation: Center for Biological Psychiatry, Beijing Hui-Long-Guan Hospital, Beijing, China. zhiren75@gmail.com.
authors.forename: Zhi-Ren
authors.initials: ZR
authors.lastname: Wang
authors.affiliation: School of Applied Psychology and Behavioral Basis of Health Program, Griffith Health Institute, Griffith University, Brisbane, Australia. d.shum@griffith.edu.au.|Menzies Health Institute Queensland and School of Applied Psychology, Griffith University, Gold Coast, Australia. d.shum@griffith.edu.au.
authors.forename: David H K
authors.initials: DH
authors.lastname: Shum
authors.affiliation: Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China. rckchan@psych.ac.cn.|Institute of Psychology, Chinese Academy of Sciences, 16 Lincui Road, Beijing, 100101, China. rckchan@psych.ac.cn.
authors.forename: Raymond C K
authors.initials: RC
authors.lastname: Chan
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000188:drug therapy / Q000473:pathology*; D002540:Cerebral Cortex / Q000473:pathology*; D003865:Major Depressive Disorder / Q000188:drug therapy / Q000473:pathology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010865:Pilot Projects
chemical_list: D014150:Antipsychotic Agents