Motivational differences in unipolar and bipolar depression, manic bipolar, acute and stable phase schizophrenia.

Affiliation

Yang X(1), Huang J(2), Harrision P(3), Roser ME(4), Tian K(5), Wang D(6), Liu G(7).
Author information:
(1)Department of Psychology, Hunan Agricultural University, Changsha, China; Brain Research & Imaging Centre, School of Psychology, Cognition Institute, Faculty of Health & Human Sciences, Plymouth University, UK.. Electronic address: [Email]
(2)Neuropsychology and Applied Cognitive Neuroscience Laboratory, Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Science, Beijing, China. Electronic address: [Email]
(3)Centre for Affective Disorders, Psychological Medicine, Institute of Psychiatry, Psychology & Neuroscience, King's College London, London, UK.. Electronic address: [Email]
(4)Brain Research & Imaging Centre, School of Psychology, Cognition Institute, Faculty of Health & Human Sciences, Plymouth University, UK.. Electronic address: [Email]
(5)Department of Psychology, Hunan Agricultural University, Changsha, China. Electronic address: [Email]
(6)Department of Psychology, Hunan Agricultural University, Changsha, China. Electronic address: [Email]
(7)Department of psychiatry, Brains Hospital of Hunan province, Changsha, China. Electronic address: [Email]

Abstract

BACKGROUND: Motivational anhedonia has been observed in patients with a wide range of mental disorders. However, the similarity and uniqueness of this deficit across diagnostic groups has not been thoroughly investigated. METHOD: The study compared motivational deficits in 37 patients with major depressive disorder (MDD), 32 with bipolar depression, 33 with manic bipolar disorder (BD), 30 with acute phase and 33 with stable phase schizophrenia, as well as 47 healthy controls. Participants were administered the Effort-Expenditure for Reward Task which measures allocation of effort between a high-effort and a low-effort task for monetary rewards at varying magnitudes and probabilities. RESULTS: Compared with healthy controls, BD manic, acute and stable phase schizophrenia patients were significantly less likely to choose the high-effort task in the high reward magnitude condition. BD manic and acute phase schizophrenia patients were significantly less likely to choose the high-effort task in the high probability condition. Acute and stable phase schizophrenia patients made less effort in the high estimated value condition. Bipolar manic patients made excessive effort in low estimated value but less effort in high estimated value. Contrary to expectations, both the unipolar and bipolar depression patients did not differ significantly from healthy controls in reward magnitude, probability, and estimated value conditions. Anhedonia and negative symptoms were associated with fewer high-effort task choices in schizophrenia patients. CONCLUSION: Motivation anhedonia showed distinct patterns across psychiatric patients: acute phase schizophrenia was the most severely affected, bipolar mania was similar to schizophrenia, but bipolar depression was similar to unipolar depression.