Recruitment of inhibition and excitation across mouse visual cortex depends on the hierarchy of interconnecting areas

  1. Rinaldo David D'Souza  Is a corresponding author
  2. Andrew Max Meier
  3. Pawan Bista
  4. Quanxin Wang
  5. Andreas Burkhalter  Is a corresponding author
  1. Washington University School of Medicine, United States
  2. Allen Institute for Brain Science, United States

Abstract

Diverse features of sensory stimuli are selectively processed in distinct brain areas. The relative recruitment of inhibitory and excitatory neurons within an area controls the gain of neurons for appropriate stimulus coding. We examined how such a balance of inhibition and excitation is differentially recruited across multiple levels of a cortical hierarchy by mapping the locations and strengths of synaptic inputs to pyramidal and parvalbumin (PV)-expressing neurons in feedforward and feedback pathways interconnecting primary (V1) and two higher visual areas. While interareal excitation was stronger in PV than in pyramidal neurons in all layer 2/3 pathways, we observed a gradual scaling down of the inhibition/excitation ratio from the most feedforward to the most feedback pathway. Our results indicate that interareal gain control depends on the hierarchical position of the source and the target, the direction of information flow through the network, and the laminar location of target neurons.

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Author details

  1. Rinaldo David D'Souza

    Department of Neuroscience, Washington University School of Medicine, St. Louis, United States
    For correspondence
    dsouzar@wustl.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9028-1990
  2. Andrew Max Meier

    Department of Neuroscience, Washington University School of Medicine, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  3. Pawan Bista

    Department of Neuroscience, Washington University School of Medicine, St. Louis, United States
    Competing interests
    The authors declare that no competing interests exist.
  4. Quanxin Wang

    Allen Institute for Brain Science, Seattle, United States
    Competing interests
    The authors declare that no competing interests exist.
  5. Andreas Burkhalter

    Department of Neuroscience, Washington University School of Medicine, St. Louis, United States
    For correspondence
    burkhala@wustl.edu
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-5140-3657

Funding

National Eye Institute (R01 EY016184)

  • Andreas Burkhalter

McDonnell Center for Systems Neuroscience

  • Andreas Burkhalter

National Eye Institute (R01 EY022090)

  • Andreas Burkhalter

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 approved by the Institutional Animal Care and Use Committee at Washington University (protocol numbers 20130104 and 20160093) and conformed to guidelines set by the National Institutes of Health.

Copyright

© 2016, D'Souza 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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https://doi.org/10.7554/eLife.19332

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