title: Diminished caudate and superior temporal gyrus responses to effort-based decision making in patients with first-episode major depressive disorder.
abstract: BACKGROUND
  Anhedonia, the loss of interest or pleasure in reward processing, is a hallmark feature of major depressive disorder (MDD), but its underlying neurobiological mechanism is largely unknown. The present study aimed to examine the underlying neural mechanism of reward-related decision-making in patients with MDD.
  
  
  METHODS
  We examined behavioral and neural responses to rewards in patients with first-episode MDD (N=25) and healthy controls (N=25) using the Effort-Expenditure for Rewards Task (EEfRT). The task involved choices about possible rewards of varying magnitude and probability. We tested the hypothesis that individuals with MDD would exhibit a reduced neural response in reward-related brain structures involved in cost-benefit decision-making.
  
  
  RESULTS
  Compared with healthy controls, patients with MDD showed significantly weaker responses in the left caudate nucleus when contrasting the 'high reward'-'low reward' condition, and blunted responses in the left superior temporal gyrus and the right caudate nucleus when contrasting high and low probabilities. In addition, hard tasks chosen during high probability trials were negatively correlated with superior temporal gyrus activity in MDD patients, while the same choices were negatively correlated with caudate nucleus activity in healthy controls.
  
  
  CONCLUSIONS
  These results indicate that reduced caudate nucleus and superior temporal gyrus activation may underpin abnormal cost-benefit decision-making in MDD.
authors.affiliation: Mental Health Institute, The Second Xiangya Hospital, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China; College of Business, Hunan Agricultural University, Changsha, China.
authors.forename: Xin-hua
authors.initials: XH
authors.lastname: Yang
authors.affiliation: Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Huang
authors.affiliation: College of Business, Hunan Agricultural University, Changsha, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Lan
authors.affiliation: College of Business, Hunan Agricultural University, Changsha, China.
authors.forename: Cui-ying
authors.initials: CY
authors.lastname: Zhu
authors.affiliation: School of Public Health, Central South University, Changsha, China.
authors.forename: Xiao-qun
authors.initials: XQ
authors.lastname: Liu
authors.affiliation: Mental Health Institute, The Second Xiangya Hospital, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China.
authors.forename: Ye-fei
authors.initials: YF
authors.lastname: Wang
authors.affiliation: Castle Peak Hospital, Hong Kong Special Administrative Region, China.
authors.forename: Eric F C
authors.initials: EF
authors.lastname: Cheung
authors.affiliation: Mental Health Institute, The Second Xiangya Hospital, National Technology Institute of Psychiatry, Key Laboratory of Psychiatry and Mental Health of Hunan Province, Central South University, Changsha, Hunan 410011, China. Electronic address: xiegr2000@126.com.
authors.forename: Guang-rong
authors.initials: GR
authors.lastname: Xie
authors.affiliation: Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China. Electronic address: rckchan@psych.ac.cn.
authors.forename: Raymond C K
authors.initials: RC
authors.lastname: Chan
mesh_terms: D000328:Adult; D059445:Anhedonia / Q000502:physiology; D001931:Brain Mapping; D002421:Caudate Nucleus / Q000503:physiopathology*; D003657:Decision Making / Q000502:physiology*; D003865:Major Depressive Disorder / Q000503:physiopathology* / Q000523:psychology; D005260:Female; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009042:Motivation / Q000502:physiology*; D009483:Neuropsychological Tests; D011336:Probability; D011569:Psychiatric Status Rating Scales; D012201:Reward; D012815:Signal Processing, Computer-Assisted; D013702:Temporal Lobe / Q000503:physiopathology*
keywords: Anhedonia; Depression; Effort-based decision-making; Motivation; Reward processing