Cerebellar climbing fibers encode expected reward size

  1. Noga Larry  Is a corresponding author
  2. Merav Yarkoni
  3. Adi Lixenberg
  4. Mati Joshua
  1. Hebrew University of Jerusalem, Israel

Abstract

Climbing fiber inputs to the cerebellum encode error signals that instruct learning. Recently, evidence has accumulated to suggest that the cerebellum is also involved in the processing of reward. To study how rewarding events are encoded, we recorded the activity of climbing fibers when monkeys were engaged in an eye movement task. At the beginning of each trial, the monkeys were cued to the size of the reward that would be delivered upon successful completion of the trial. Climbing fiber activity increased when the monkeys were presented with a cue indicating a large reward size. Reward size did not modulate activity at reward delivery or during eye movements. Comparison between climbing fiber and simple spike activity indicated different interactions for coding of movement and reward. These results indicate that climbing fibers encode the expected reward size and suggest a general role of the cerebellum in associative learning beyond error correction.

Data availability

The data used in this paper is available in:https://github.com/MatiJlab

Article and author information

Author details

  1. Noga Larry

    Edmond and Lily Safra Center for Brain Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
    For correspondence
    noga.larry@mail.huji.ac.il
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8750-2182
  2. Merav Yarkoni

    Edmond and Lily Safra Center for Brain Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
    Competing interests
    The authors declare that no competing interests exist.
  3. Adi Lixenberg

    Edmond and Lily Safra Center for Brain Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
    Competing interests
    The authors declare that no competing interests exist.
  4. Mati Joshua

    Edmond and Lily Safra Center for Brain Sciences, Hebrew University of Jerusalem, Jerusalem, Israel
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-2602-3334

Funding

H2020 European Research Council (imove 755745)

  • Mati Joshua

Human Frontier Science Program (CDA 00056)

  • Mati Joshua

Israel Science Foundation (38017)

  • Noga Larry

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

Ethics

Animal experimentation: All the procedures described in this paper were approved in advance by the Institutional Animal Care and Use Committees of the Hebrew University of Jerusalem (ethics approval number MD­15­14585­4) and were in strict compliance with the National Institutes of Health Guide for the Care and Use of Laboratory Animals.

Reviewing Editor

  1. Jennifer L Raymond, Stanford University School of Medicine, United States

Publication history

  1. Received: March 14, 2019
  2. Accepted: October 24, 2019
  3. Accepted Manuscript published: October 29, 2019 (version 1)
  4. Version of Record published: November 11, 2019 (version 2)

Copyright

© 2019, Larry 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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  1. Noga Larry
  2. Merav Yarkoni
  3. Adi Lixenberg
  4. Mati Joshua
(2019)
Cerebellar climbing fibers encode expected reward size
eLife 8:e46870.
https://doi.org/10.7554/eLife.46870

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