Sparse activity of identified dentate granule cells during spatial exploration

  1. Maria Diamantaki
  2. Markus Frey
  3. Philipp Berens
  4. Patricia Preston-Ferrer  Is a corresponding author
  5. Andrea Burgalossi  Is a corresponding author
  1. Werner-Reichardt Centre for Integrative Neuroscience, Germany

Abstract

In the dentate gyrus - a key component of spatial memory circuits - granule cells (GCs) are known to be morphologically diverse and to display heterogeneous activity profiles during behavior. To resolve structure-function relationships, we juxtacellularly recorded and labeled single GCs in freely-moving rats. We found that the vast majority of neurons were silent during exploration. Most active GCs displayed a characteristic spike waveform, fired at low rates and showed spatial activity. Primary dendritic parameters were sufficient for classifying neurons as active or silent with high accuracy. Our data thus support a sparse coding scheme in the dentate gyrus and provide a possible link between structural and functional heterogeneity among the GC population.

Article and author information

Author details

  1. Maria Diamantaki

    Werner-Reichardt Centre for Integrative Neuroscience, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  2. Markus Frey

    Werner-Reichardt Centre for Integrative Neuroscience, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
  3. Philipp Berens

    Werner-Reichardt Centre for Integrative Neuroscience, Tübingen, Germany
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0199-4727
  4. Patricia Preston-Ferrer

    Werner-Reichardt Centre for Integrative Neuroscience, Tübingen, Germany
    For correspondence
    patricia.preston@cin.uni-tuebingen.de
    Competing interests
    The authors declare that no competing interests exist.
  5. Andrea Burgalossi

    Werner-Reichardt Centre for Integrative Neuroscience, Tübingen, Germany
    For correspondence
    andrea.burgalossi@cin.uni-tuebingen.de
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0039-3599

Funding

Deutsche Forschungsgemeinschaft (EXC 307)

  • Maria Diamantaki
  • Markus Frey
  • Philipp Berens
  • Patricia Preston-Ferrer
  • Andrea Burgalossi

Bundesministerium für Bildung und Forschung (FKZ 01GQ1601)

  • Philipp Berens

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 experimental procedures were performed according to the German guidelines on animal welfare and approved by the local institution in charge of experiments using animals (Regierungspraesidium Tuebingen, permit numbers CIN2/14, CIN/5/14 and CIN/814).

Copyright

© 2016, Diamantaki 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. Maria Diamantaki
  2. Markus Frey
  3. Philipp Berens
  4. Patricia Preston-Ferrer
  5. Andrea Burgalossi
(2016)
Sparse activity of identified dentate granule cells during spatial exploration
eLife 5:e20252.
https://doi.org/10.7554/eLife.20252

Share this article

https://doi.org/10.7554/eLife.20252

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