Dopamine role in learning and action inference

  1. Rafal Bogacz  Is a corresponding author
  1. University of Oxford, United Kingdom

Abstract

This paper describes a framework for modelling dopamine function in the mammalian brain. It proposes that both learning and action planning involve processes minimizing prediction errors encoded by dopaminergic neurons. In this framework, dopaminergic neurons projecting to different parts of the striatum encode errors in predictions made by the corresponding systems within the basal ganglia. The dopaminergic neurons encode differences between rewards and expectations in the goal-directed system, and differences between the chosen and habitual actions in the habit system. These prediction errors trigger learning about rewards and habit formation, respectively. Additionally, dopaminergic neurons in the goal-directed system play a key role in action planning: They compute the difference between an available reward and the reward expected from the current motor plan, and they facilitate action planning until this difference diminishes. Presented models account for dopaminergic responses during movements, effects of dopamine depletion on behaviour, and make several experimental predictions.

Data availability

Matlab codes for all simulations described in the paper are available at MRC Brain Network Dynamics Unit Data Sharing Platform(https://data.mrc.ox.ac.uk/data-set/simulations-action-inference).

The following data sets were generated

Article and author information

Author details

  1. Rafal Bogacz

    Medical Research Council Brain Network Dynamics Unit, University of Oxford, Oxford, United Kingdom
    For correspondence
    rafal.bogacz@ndcn.ox.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-8994-1661

Funding

Medical Research Council (MC_UU_12024/5)

  • Rafal Bogacz

Medical Research Council (MC_UU_00003/1)

  • Rafal Bogacz

Biotechnology and Biological Sciences Research Council (BB/S006338/1)

  • Rafal Bogacz

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Thorsten Kahnt, Northwestern University, United States

Version history

  1. Received: November 1, 2019
  2. Accepted: July 6, 2020
  3. Accepted Manuscript published: July 7, 2020 (version 1)
  4. Version of Record published: July 30, 2020 (version 2)

Copyright

© 2020, Bogacz

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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  1. Rafal Bogacz
(2020)
Dopamine role in learning and action inference
eLife 9:e53262.
https://doi.org/10.7554/eLife.53262

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https://doi.org/10.7554/eLife.53262

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