1. Neuroscience
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Cross-frequency synchronization connects networks of fast and slow oscillations during visual working memory maintenance

  1. Felix Siebenhühner
  2. Sheng H Wang
  3. J Matias Palva
  4. Satu Palva  Is a corresponding author
  1. University of Helsinki, Finland
Research Article
  • Cited 48
  • Views 2,513
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Cite this article as: eLife 2016;5:e13451 doi: 10.7554/eLife.13451

Abstract

Neuronal activity in sensory and fronto-parietal (FP) areas underlies the representation and attentional control, respectively, of sensory information maintained in visual working memory (VWM). Within these regions, beta/gamma phase-synchronization supports the integration of sensory functions, while synchronization in theta/alpha bands supports the regulation of attentional functions. A key challenge is to understand which mechanisms integrate neuronal processing across these distinct frequencies and thereby the sensory and attentional functions. We investigated whether such integration could be achieved by cross-frequency phase synchrony (CFS). Using concurrent magneto- and electroencephalography, we found that CFS was load-dependently enhanced between theta and alpha-gamma and between alpha and beta/gamma oscillations during VWM maintenance among visual, FP, and dorsal attention (DA) systems. CFS also connected the hubs of within-frequency-synchronized networks and its strength predicted individual VWM capacity. We propose that CFS integrates processing among synchronized neuronal networks from theta to gamma frequencies to link sensory and attentional functions.

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Article and author information

Author details

  1. Felix Siebenhühner

    Neuroscience Center, University of Helsinki, Helsinki, Finland
    Competing interests
    The authors declare that no competing interests exist.
  2. Sheng H Wang

    Neuroscience Center, University of Helsinki, Helsinki, Finland
    Competing interests
    The authors declare that no competing interests exist.
  3. J Matias Palva

    Neuroscience Center, University of Helsinki, Helsinki, Finland
    Competing interests
    The authors declare that no competing interests exist.
  4. Satu Palva

    Neuroscience Center, University of Helsinki, Helsinki, Finland
    For correspondence
    satu.palva@helsinki.fi
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9496-7391

Funding

Suomen Akatemia (SA1126927, SA266402,)

  • Satu Palva

Helsinki University Research Grants (788/51/2010)

  • Satu Palva

Brain and Mind doctoral program

  • Felix Siebenhühner

Suomen Akatemia (SA253130, SA281414, SA256472)

  • J Matias Palva

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

Ethics

Human subjects: This study was approved by the ethical committee of Helsinki University Central hospital and was performed according to the Declaration of Helsinki. Written informed consent was obtained from each subject prior to the experiment.

Reviewing Editor

  1. Maurizio Corbetta, Washington University, United States

Publication history

  1. Received: December 1, 2015
  2. Accepted: September 24, 2016
  3. Accepted Manuscript published: September 26, 2016 (version 1)
  4. Version of Record published: October 19, 2016 (version 2)

Copyright

© 2016, Siebenhühner 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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