1. Computational and Systems Biology
  2. Neuroscience
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A cholinergic feedback circuitto regulate striatal population uncertainty and optimize reinforcement learning

  1. Nicholas T Franklin
  2. Michael J Frank  Is a corresponding author
  1. Brown University, United States
Research Article
  • Cited 25
  • Views 2,181
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Cite this article as: eLife 2015;4:e12029 doi: 10.7554/eLife.12029


Convergent evidence suggeststhat the basal ganglia support reinforcement learning by adjusting action values according to reward prediction errors. However, adaptive behavior in stochasticenvironments requires the consideration of uncertainty to dynamically adjust the learning rate. We consider how cholinergic tonically active interneurons (TANs) may endow the striatum with such a mechanismin computational models spanning three Marr's levels of analysis. In the neural model, TANs modulate the excitability of spiny neurons, theirpopulation response to reinforcement, and hence the effective learning rate. Long TAN pauses facilitated robustness to spuriousoutcomes by increasing divergence in synaptic weights between neurons coding for alternative action values,whereas short TAN pauses facilitated stochastic behavior but increased responsiveness to change-points in outcome contingencies.A feedback control system allowed TAN pauses to be dynamically modulated by uncertainty across the spiny neuron population,allowing the system to self-tune and optimizeperformance across stochastic environments.

Article and author information

Author details

  1. Nicholas T Franklin

    Department of Cognitive, Linguistic and Psychological Sciences, Brown Institute for Brain Science, Brown University, Providence, United States
    Competing interests
    No competing interests declared.
  2. Michael J Frank

    Department of Cognitive, Linguistic and Psychological Sciences, Brown Institute for Brain Science, Brown University, Providence, United States
    For correspondence
    Competing interests
    Michael J Frank, Reviewing editor, eLife.

Reviewing Editor

  1. Upinder S Bhalla, National Centre for Biological Sciences, India

Publication history

  1. Received: October 3, 2015
  2. Accepted: December 24, 2015
  3. Accepted Manuscript published: December 25, 2015 (version 1)
  4. Accepted Manuscript updated: January 12, 2016 (version 2)
  5. Accepted Manuscript updated: January 13, 2016 (version 3)
  6. Version of Record published: February 10, 2016 (version 4)


© 2015, Franklin & Frank

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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