Disrupted reward circuits is associated with cognitive deficits and depression severity in major depressive disorder

J Psychiatr Res. 2017 Jan:84:9-17. doi: 10.1016/j.jpsychires.2016.09.016. Epub 2016 Sep 17.

Abstract

Neuroimaging studies have demonstrated that major depressive disorder (MDD) patients show blunted activity responses to reward-related tasks. However, whether abnormal reward circuits affect cognition and depression in MDD patients remains unclear. Seventy-five drug-naive MDD patients and 42 cognitively normal (CN) subjects underwent a resting-state functional magnetic resonance imaging scan. The bilateral nucleus accumbens (NAc) were selected as seeds to construct reward circuits across all subjects. A multivariate linear regression analysis was employed to investigate the neural substrates of cognitive function and depression severity on the reward circuits in MDD patients. The common pathway underlying cognitive deficits and depression was identified with conjunction analysis. Compared with CN subjects, MDD patients showed decreased reward network connectivity that was primarily located in the prefrontal-striatal regions. Importantly, distinct and common neural pathways underlying cognition and depression were identified, implying the independent and synergistic effects of cognitive deficits and depression severity on reward circuits. This study demonstrated that disrupted topological organization within reward circuits was significantly associated with cognitive deficits and depression severity in MDD patients. These findings suggest that in addition to antidepressant treatment, normalized reward circuits should be a focus and a target for improving depression and cognitive deficits in MDD patients.

Keywords: Cognitive impairment; Intrinsic functional connectivity; Major depressive disorder; Nucleus accumbens; Reward circuits.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brain / diagnostic imaging
  • Brain / physiopathology*
  • Brain Mapping
  • Depressive Disorder, Major / diagnostic imaging
  • Depressive Disorder, Major / physiopathology*
  • Depressive Disorder, Major / psychology*
  • Female
  • Humans
  • Linear Models
  • Magnetic Resonance Imaging
  • Male
  • Mental Status Schedule
  • Multivariate Analysis
  • Neural Pathways / diagnostic imaging
  • Neural Pathways / physiopathology
  • Neuropsychological Tests
  • Psychiatric Status Rating Scales
  • Reward*
  • Severity of Illness Index