Effort-cost computation in a transdiagnostic psychiatric sample: Differences among patients with schizophrenia, bipolar disorder, and major depressive disorder

Psych J. 2020 Apr;9(2):210-222. doi: 10.1002/pchj.316. Epub 2019 Nov 6.

Abstract

Amotivational symptoms are observed in schizophrenia (SCZ), bipolar disorder (BD), and major depressive disorder (MDD). Effort-cost computation may be a potential contributor to amotivation transdiagnostically. This study examined effort-cost computation in these three diagnostic groups. This study recruited 141 outpatients (49 SCZ, 52 non-psychotic BD, and 40 non-psychotic MDD) and 57 healthy controls (HCs). We administered the Effort-Expenditure for Reward Task (EEfRT), which manipulated different levels of reward magnitude and probability relating to a high and low physical effort task. There were significant interactions between group and reward magnitude, group and reward probability, and group and expected value on the percentage of high-effort choices. SCZ, BD, and MDD patients made comparably fewer high-effort choices than HCs in the high-reward magnitude, high-reward probability, and high-expected-value conditions. Self-reported amotivation did not correlate with decision-making on the EEfRT. Our findings suggest that reduced effort expenditure for reward is a transdiagnostic phenotype in SCZ, BD, and MDD.

MeSH terms

  • Adult
  • Bipolar Disorder / complications*
  • Brief Psychiatric Rating Scale / statistics & numerical data
  • China
  • Decision Making / physiology
  • Depressive Disorder, Major / complications*
  • Female
  • Humans
  • Male
  • Motivation / physiology*
  • Patients / statistics & numerical data*
  • Probability
  • Reward
  • Schizophrenia / complications*
  • Schizophrenic Psychology