1. Neuroscience
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Human complex exploration strategies are enriched by noradrenaline-modulated heuristics

  1. Magda Dubois  Is a corresponding author
  2. Johanna Habicht
  3. Jochen Michely
  4. Rani Moran
  5. Raymond J Dolan
  6. Tobias U Hauser  Is a corresponding author
  1. University College London, United Kingdom
Research Article
  • Cited 3
  • Views 1,419
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Cite this article as: eLife 2021;10:e59907 doi: 10.7554/eLife.59907

Abstract

An exploration-exploitation trade-off, the arbitration between sampling a lesser-known against a known rich option, is thought to be solved using computationally demanding exploration algorithms. Given known limitations in human cognitive resources, we hypothesised the presence of additional cheaper strategies. We examined for such heuristics in choice behaviour where we show this involves a value-free random exploration, that ignores all prior knowledge, and a novelty exploration that targets novel options alone. In a double-blind, placebo-controlled drug study, assessing contributions of dopamine (400mg amisulpride) and noradrenaline (40mg propranolol), we show that value-free random exploration is attenuated under the influence of propranolol, but not under amisulpride. Our findings demonstrate that humans deploy distinct computationally cheap exploration strategies and where value-free random exploration is under noradrenergic control.

Data availability

All necessary resources are publicly available at: https://github.com/MagDub.

Article and author information

Author details

  1. Magda Dubois

    Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom
    For correspondence
    magda.dubois.18@ucl.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
  2. Johanna Habicht

    Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  3. Jochen Michely

    Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  4. Rani Moran

    Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7641-2402
  5. Raymond J Dolan

    The Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9356-761X
  6. Tobias U Hauser

    Max Planck UCL Centre for Computational Psychiatry and Ageing Research, University College London, London, United Kingdom
    For correspondence
    t.hauser@ucl.ac.uk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7997-8137

Funding

Max-Planck-Gesellschaft

  • Magda Dubois

Wellcome Sir Hendry Dale Fellowship (211155/Z/18/Z)

  • Tobias U Hauser

Jacobs Foundation (2017-1261-04)

  • Tobias U Hauser

Wellcome Trust Investigator Award (098362/Z/12/Z)

  • 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 UCL research committee (REC No 6218/002) and all subjects provided written informed consent

Reviewing Editor

  1. Thorsten Kahnt, Northwestern University, United States

Publication history

  1. Received: June 12, 2020
  2. Accepted: January 3, 2021
  3. Accepted Manuscript published: January 4, 2021 (version 1)
  4. Version of Record published: January 19, 2021 (version 2)

Copyright

© 2021, Dubois 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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