Dissociated sequential activity and stimulus encoding in the dorsomedial striatum during spatial working memory

Abstract

Several lines of evidence suggest that the striatum has an important role in spatial working memory. The neural dynamics in the striatum have been described in tasks with short delay periods (1-4s), but remain largely uncharacterized for tasks with longer delay periods. We collected and analyzed single unit recordings from the dorsomedial striatum of rats performing a spatial working memory task with delays up to 10s. We found that neurons were activated sequentially, with the sequences spanning the entire delay period. Surprisingly, this sequential activity was dissociated from stimulus encoding activity, which was present in the same neurons, but preferentially appeared towards the onset of the delay period. These observations contrast with descriptions of sequential dynamics during similar tasks in other brains areas, and clarify the contribution of the striatum in spatial working memory.

Article and author information

Author details

  1. Hessameddin Akhlaghpour

    Princeton Neuroscience Institute, Princeton University, Princeton, United States
    Competing interests
    The authors declare that no competing interests exist.
  2. Joost Wiskerke

    Princeton Neuroscience Institute, Princeton University, Princeton, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Jung Yoon Choi

    Princeton Neuroscience Institute, Princeton University, Princeton, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Joshua P Taliaferro

    Princeton Neuroscience Institute, Princeton University, Princeton, United States
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-6051-8635
  5. Jennifer Au

    Princeton Neuroscience Institute, Princeton University, Princeton, United States
    Competing interests
    The authors declare that no competing interests exist.
  6. Ilana Witten

    Princeton Neuroscience Institute, Princeton University, Princeton, United States
    For correspondence
    iwitten@princeton.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0548-2160

Funding

NSF Office of the Director (GRFP)

  • Hessameddin Akhlaghpour

NIH Office of the Director (5R01MH106689-02)

  • Ilana Witten

McKnight Foundation

  • Ilana Witten

Pew Charitable Trusts

  • Ilana Witten

NIH Office of the Director (1 DP2 DA035149-01)

  • Ilana Witten

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

Reviewing Editor

  1. Naoshige Uchida, Harvard University, United States

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (1876-15) of Princeton University. All surgery was performed under anesthesia, and every effort was made to minimize suffering.

Version history

  1. Received: July 11, 2016
  2. Accepted: September 15, 2016
  3. Accepted Manuscript published: September 16, 2016 (version 1)
  4. Version of Record published: October 6, 2016 (version 2)

Copyright

© 2016, Akhlaghpour 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. Hessameddin Akhlaghpour
  2. Joost Wiskerke
  3. Jung Yoon Choi
  4. Joshua P Taliaferro
  5. Jennifer Au
  6. Ilana Witten
(2016)
Dissociated sequential activity and stimulus encoding in the dorsomedial striatum during spatial working memory
eLife 5:e19507.
https://doi.org/10.7554/eLife.19507

Share this article

https://doi.org/10.7554/eLife.19507

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