1. Neuroscience
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Differential inhibition onto developing and mature granule cells generates high-frequency filters with variable gain

  1. María Belén Pardi
  2. Mora Belén Ogando
  3. Alejandro F Schinder
  4. Antonia Marin-Burgin  Is a corresponding author
  1. Instituto de Investigación en Biomedicina de Buenos Aires - CONICET - Partner Institute of the Max Planck Society, Argentina
  2. Leloir Institute -CONICET, Argentina
Research Article
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Cite this article as: eLife 2015;4:e08764 doi: 10.7554/eLife.08764

Abstract

Adult hippocampal neurogenesis provides the dentate gyrus with heterogeneous populations of granule cells (GC) originated at different times. The contribution of these cells to information encoding is under current investigation. Here we show that incoming spike trains activate different populations of GC determined by the stimulation frequency and GC age. Immature GC respond to a wider range of stimulus frequencies, whereas mature GC are less responsive at high frequencies. This difference is dictated by feed forward inhibition, which restricts mature GC activation. Yet, the stronger inhibition of mature GC results in a higher temporal fidelity compared to that of immature GC. Thus, hippocampal inputs activate two populations of neurons with variable frequency filters: immature cells, with wide‐range responses, that are reliable transmitters of the incoming frequency, and mature neurons, with narrow frequency response, that are precise at informing the beginning of the stimulus, but with a sparse activity.

Article and author information

Author details

  1. María Belén Pardi

    Instituto de Investigación en Biomedicina de Buenos Aires - CONICET - Partner Institute of the Max Planck Society, Buenos Aires, Argentina
    Competing interests
    The authors declare that no competing interests exist.
  2. Mora Belén Ogando

    Instituto de Investigación en Biomedicina de Buenos Aires - CONICET - Partner Institute of the Max Planck Society, Buenos Aires, Argentina
    Competing interests
    The authors declare that no competing interests exist.
  3. Alejandro F Schinder

    Laboratory of Neuronal Plasticity, Leloir Institute -CONICET, Buenos Aires, Argentina
    Competing interests
    The authors declare that no competing interests exist.
  4. Antonia Marin-Burgin

    Instituto de Investigación en Biomedicina de Buenos Aires - CONICET - Partner Institute of the Max Planck Society, Buenos Aires, Argentina
    For correspondence
    aburgin@ibioba-mpsp-conicet.gov.ar
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Animal experimentation: Experimental protocols were approved by the Institutional Animal Care and Use Committee of the Fundación Instituto Leloir (Protocols Number 2009 08 37 and 64/2015, IACUC, Leloir Institute Foundation) according to the Principles for Biomedical Research involving animals of the Council for International Organizations for Medical Sciences and provisions stated in the Guide for the Care and Use of Laboratory Animals.

Reviewing Editor

  1. Marlene Bartos, Albert-Ludwigs-Universität Freiburg, Germany

Publication history

  1. Received: May 16, 2015
  2. Accepted: July 10, 2015
  3. Accepted Manuscript published: July 11, 2015 (version 1)
  4. Version of Record published: July 31, 2015 (version 2)

Copyright

© 2015, Pardi 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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