Dopamine enhances model-free credit assignment through boosting of retrospective model-based inference
Abstract
Dopamine is implicated in representing model-free (MF) reward prediction errors a as well as influencing model-based (MB) credit assignment and choice. Putative cooperative interactions between MB and MF systems include a guidance of MF credit assignment by MB inference. Here, we used a double-blind, placebo-controlled, within-subjects design to test an hypothesis that enhancing dopamine levels boosts the guidance of MF credit assignment by MB inference. In line with this, we found that levodopa enhanced guidance of MF credit assignment by MB inference, without impacting MF and MB influences directly. This drug effect correlated negatively with a dopamine-dependent change in purely MB credit assignment, possibly reflecting a trade-off between these two MB components of behavioural control. Our findings of a dopamine boost in MB inference guidance of MF learning highlights a novel DA influence on MB-MF cooperative interactions.
Data availability
Necessary source data files are openly available at: https://osf.io/4dfkv/.
Article and author information
Author details
Funding
Wellcome Trust (098362/Z/12/Z)
- Raymond J Dolan
Max-Planck-Gesellschaft (Open-access funding)
- Lorenz Deserno
- Rani Moran
- Peter Dayan
- Raymond J Dolan
Deutsche Forschungsgemeinschaft (402170461)
- Lorenz Deserno
- Raymond J Dolan
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: The study was approved by the University College London Research Ethics Committee (Project ID 11285/001). Subjects gave written informed consent before the experiment.
Copyright
© 2021, Deserno 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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