title: Reduction in ventral striatal activity when anticipating a reward in depression and schizophrenia: a replicated cross-diagnostic finding.
abstract: In the research domain framework (RDoC), dysfunctional reward expectation has been proposed to be a cross-diagnostic domain in psychiatry, which may contribute to symptoms common to various neuropsychiatric conditions, such as anhedonia or apathy/avolition. We used a modified version of the Monetary Incentive Delay (MID) paradigm to obtain functional MRI images from 22 patients with schizophrenia, 24 with depression and 21 controls. Anhedonia and other symptoms of depression, and overall positive and negative symptomatology were also measured. We hypothesized that the two clinical groups would have a reduced activity in the ventral striatum when anticipating reward (compared to anticipation of a neutral outcome) and that striatal activation would correlate with clinical measures of motivational problems and anhedonia. Results were consistent with the first hypothesis: two clusters in both the left and right ventral striatum were found to differ between the groups in reward anticipation. Post-hoc analysis showed that this was due to higher activation in the controls compared to the schizophrenia and the depression groups in the right ventral striatum, with activation differences between depression and controls also seen in the left ventral striatum. No differences were found between the two patient groups, and there were no areas of abnormal cortical activation in either group that survived correction for multiple comparisons. Reduced ventral striatal activity was related to greater anhedonia and overall depressive symptoms in the schizophrenia group, but not in the participants with depression. Findings are discussed in relation to previous literature but overall are supporting evidence of reward system dysfunction across the neuropsychiatric continuum, even if the specific clinical relevance is still not fully understood. We also discuss how the RDoC approach may help to solve some of the replication problems in psychiatric fMRI research.
authors.affiliation: Department of Psychiatry, University of Cambridge Cambridge, UK.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Arrondo
authors.affiliation: Department of Psychiatry, University of Cambridge Cambridge, UK.
authors.forename: Nuria
authors.initials: N
authors.lastname: Segarra
authors.affiliation: Department of Psychiatry, University of Cambridge Cambridge, UK.
authors.forename: Antonio
authors.initials: A
authors.lastname: Metastasio
authors.affiliation: Department of Psychiatry, University of Cambridge Cambridge, UK ; Wellcome Trust-MRC Institute of Metabolic Science Cambridge, UK ; Cambridgeshire and Peterborough NHS Foundation Trust UK.
authors.forename: Hisham
authors.initials: H
authors.lastname: Ziauddeen
authors.affiliation: Department of Psychiatry, University of Cambridge Cambridge, UK ; Cambridgeshire and Peterborough NHS Foundation Trust UK.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Spencer
authors.affiliation: Department of Psychiatry, University of Cambridge Cambridge, UK.
authors.forename: Niels R
authors.initials: NR
authors.lastname: Reinders
authors.affiliation: Department of Psychiatry, University of Cambridge Cambridge, UK ; Cambridgeshire and Peterborough NHS Foundation Trust UK ; Psychiatric Liaison Service, Ipswich Hospital Norfolk and Suffolk NHS Foundation Trust, UK.
authors.forename: Robert B
authors.initials: RB
authors.lastname: Dudas
authors.affiliation: Department of Psychology, University of Cambridge Cambridge, UK ; Behavioural and Clinical Neuroscience Institute, University of Cambridge Cambridge, UK.
authors.forename: Trevor W
authors.initials: TW
authors.lastname: Robbins
authors.affiliation: Department of Psychiatry, University of Cambridge Cambridge, UK ; Wellcome Trust-MRC Institute of Metabolic Science Cambridge, UK ; Cambridgeshire and Peterborough NHS Foundation Trust UK ; Behavioural and Clinical Neuroscience Institute, University of Cambridge Cambridge, UK.
authors.forename: Paul C
authors.initials: PC
authors.lastname: Fletcher
authors.affiliation: Department of Psychiatry, University of Cambridge Cambridge, UK ; Cambridgeshire and Peterborough NHS Foundation Trust UK ; Behavioural and Clinical Neuroscience Institute, University of Cambridge Cambridge, UK.
authors.forename: Graham K
authors.initials: GK
authors.lastname: Murray
keywords: depressive symptoms; monetary incentive delay; research domain framework; reward system; ventral striatum