1. Neuroscience

Phase-amplitude coupling supports phase coding in human ECoG

  1. Andrew J Watrous  Is a corresponding author
  2. Lorena Deuker
  3. Juergen Fell
  4. Nikolai Axmacher
  1. University of Bonn, Germany
  2. German Center for Neurodegenerative Diseases, Germany
https://doi.org/10.7554/eLife.07886
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  1. Andrew J Watrous
  2. Lorena Deuker
  3. Juergen Fell
  4. Nikolai Axmacher
(2015)
Phase-amplitude coupling supports phase coding in human ECoG
eLife 4:e07886.
https://doi.org/10.7554/eLife.07886
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Abstract

Prior studies have shown that high-frequency activity (HFA) is modulated by the phase of low-frequency activity. This phenomenon of phase-amplitude coupling (PAC) is often interpreted as reflecting phase coding of neural representations, although evidence for this link is still lacking in humans. Here, we show that PAC indeed supports phase-dependent stimulus representations for categories. Six patients with medication-resistant epilepsy viewed images of faces, tools, houses, and scenes during simultaneous acquisition of intracranial recordings. Analyzing 167 electrodes, we observed PAC at 43% of electrodes. Further inspection of PAC revealed that category specific HFA modulations occurred at different phases and frequencies of the underlying low-frequency rhythm, permitting decoding of categorical information using the phase at which HFA events occurred. These results provide evidence for categorical phase-coded neural representations and are the first to show that PAC coincides with phase-dependent coding in the human brain.

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Author details

  1. Andrew J Watrous

    Department of Epileptology, University of Bonn, Bonn, Germany
    For correspondence
    ajw5xc@gmail.com
    Competing interests
    The authors declare that no competing interests exist.

  2. Lorena Deuker

    Department of Epileptology, University of Bonn, Bonn, Germany
    Competing interests
    The authors declare that no competing interests exist.

  3. Juergen Fell

    Department of Epileptology, University of Bonn, Bonn, Germany
    Competing interests
    The authors declare that no competing interests exist.

  4. Nikolai Axmacher

    German Center for Neurodegenerative Diseases, Bonn, Germany
    Competing interests
    The authors declare that no competing interests exist.

Ethics

Human subjects: The study was conducted according to the latest version of the Declaration of Helsinki and approved by the local ethics committee, and all patients provided written informed consent.

Copyright

© 2015, Watrous 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. Andrew J Watrous
  2. Lorena Deuker
  3. Juergen Fell
  4. Nikolai Axmacher
(2015)
Phase-amplitude coupling supports phase coding in human ECoG
eLife 4:e07886.
https://doi.org/10.7554/eLife.07886

Share this article

https://doi.org/10.7554/eLife.07886

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