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Reduced frontostriatal response to expected value and reward prediction error in remitted monozygotic twins with mood disorders and their unaffected high-risk co-twins

Published online by Cambridge University Press:  02 March 2020

Julian Macoveanu Open the ORCID record for Julian Macoveanu [Opens in a new window] ,
Iselin Meluken ,
Henry W. Chase ,
Mary L. Phillips ,
Lars Vedel Kessing ,
Hartwig Roman Siebner ,
Maj Vinberg  and
Kamilla W. Miskowiak
Julian Macoveanu*
Affiliation:
Copenhagen Affective Disorder Research Center (CADIC), Psychiatric Centre Copenhagen, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
Iselin Meluken
Affiliation:
Copenhagen Affective Disorder Research Center (CADIC), Psychiatric Centre Copenhagen, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
Henry W. Chase
Affiliation:
Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
Mary L. Phillips
Affiliation:
Department of Psychiatry, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
Lars Vedel Kessing
Affiliation:
Copenhagen Affective Disorder Research Center (CADIC), Psychiatric Centre Copenhagen, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
Hartwig Roman Siebner
Affiliation:
Danish Research Centre for Magnetic Resonance, Centre for Functional and Diagnostic Imaging and Research, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark Department of Neurology, Copenhagen University Hospital Bispebjerg, Copenhagen, Denmark Faculty of Medical and Health Sciences, Institute for Clinical Medicine, University of Copenhagen, Copenhagen, Denmark
Maj Vinberg
Affiliation:
Copenhagen Affective Disorder Research Center (CADIC), Psychiatric Centre Copenhagen, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark
Kamilla W. Miskowiak
Affiliation:
Copenhagen Affective Disorder Research Center (CADIC), Psychiatric Centre Copenhagen, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark Department of Psychology, University of Copenhagen, Copenhagen, Denmark
*
Author for correspondence: Julian Macoveanu, E-mail: [email protected]
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Abstract

Background

Depressive episodes experienced in unipolar (UD) and bipolar (BD) disorders are characterized by anhedonia and have been associated with abnormalities in reward processes related to reward valuation and error prediction. It remains however unclear whether these deficits are associated with familial vulnerability to mood disorders.

Methods

In a functional magnetic resonance imaging study, we evaluated differences in the expected value (EV) and reward prediction error (RPE) signals in ventral striatum (VS) and prefrontal cortex between three groups of monozygotic twins: affected twins in remission for either UD or BD (n = 53), their high-risk unaffected co-twins (n = 34), and low-risk twins with no family history of mood disorders (n = 25).

Results

Compared to low-risk twins, affected twins showed lower EV signal bilaterally in the frontal poles and lower RPE signal bilaterally in the VS, left frontal pole and superior frontal gyrus. The high-risk group did not show a significant change in the EV or RPE signals in frontostriatal regions, yet both reward signals were consistently lower compared with low-risk twins in all regions where the affected twins showed significant reductions.

Conclusion

Our findings strengthen the notion that reduced valuation of expected rewards and reduced error-dependent reward learning may underpin core symptom of depression such as loss of interest in rewarding activities. The trend reduction in reward-related signals in unaffected co-twins warrants further investigation of this effect in larger samples and prospective follow-up to confirm possible association with increased familial vulnerability to mood disorders.

Keywords

Bipolar disorderexpected valuefamilial riskmajor depressive disorderprediction errortwins
Type
Original Article
Information
Psychological Medicine , Volume 51 , Issue 10 , July 2021 , pp. 1637 - 1646
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Copyright
Copyright © The Author(s) 2020. Published by Cambridge University Press

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