Attenuation of dopamine-modulated prefrontal value signals underlies probabilistic reward learning deficits in old age
- Karolinska Institute, Sweden
- Umeå University, Sweden
- University College London, United Kingdom
Abstract
Probabilistic reward learning is characterised by individual differences that become acute in aging. This may be due to age-related dopamine (DA) decline affecting neural processing in striatum, prefrontal cortex, or both. We examined this by administering a probabilistic reward learning task to younger and older adults, and combining computational modelling of behaviour, fMRI and PET measurements of DA D1 availability. We found that anticipatory value signals in ventromedial prefrontal cortex (vmPFC) were attenuated in older adults. The strength of this signal predicted performance beyond age and was modulated by D1 availability in nucleus accumbens. These results uncover that a value-anticipation mechanism in vmPFC declines in aging, and that this mechanisms is associated with DA D1 receptor availability.
Article and author information
Author details
Marc Guitart-Masip
Funding
Vetenskapsrådet (VR521-2013-2589)
- Marc Guitart-Masip
Gatsby Charitable Foundation
- Peter Dayan
Alexander von Humboldt-Stiftung (Humboldt Research Award)
- Lars Bäckman
Stichting af Jochnick Foundation
- Lars Bäckman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Wolfram Schultz, University of Cambridge, United Kingdom
Ethics
Human subjects: Ethical approval was obtained from the Umeå Ethical Review Board, identifier DNR 2014-251-31M. All participants provided written informed consent prior to commencing the study.
Version history
- Received: February 28, 2017
- Accepted: August 11, 2017
- Accepted Manuscript published: September 5, 2017 (version 1)
- Version of Record published: September 11, 2017 (version 2)
Copyright
© 2017, de Boer et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Attenuation of dopamine-modulated prefrontal value signals underlies probabilistic reward learning deficits in old age
eLife 6:e26424.
https://doi.org/10.7554/eLife.26424
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