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.
- Marc Guitart-Masip
- Peter Dayan
- Lars Bäckman
- Lars Bäckman
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
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.
- Wolfram Schultz, University of Cambridge, United Kingdom
© 2017, de Boer et al.
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