Sub-second dynamics of theta-gamma coupling in Hippocampal CA1
Oscillatory brain activity reflects different internal brain states including neurons' excitatory state and synchrony among neurons. However, characterizing these states is complicated by the fact that different oscillations are often coupled, such as gamma oscillations nested in theta in the hippocampus, and changes in coupling are thought to reflect distinct states. Here, we describe a new method to separate single oscillatory cycles into distinct states based on frequency and phase coupling. Using this method, we identified four theta-gamma coupling states in rat hippocampal CA1. These states differed in abundance across behaviors, phase synchrony with other hippocampal subregions, and neural coding properties suggesting that these states are functionally distinct. We captured cycle-to-cycle changes in oscillatory coupling states and found frequent switching between theta-gamma states showing that the hippocampus rapidly shifts between different functional states. This method provides a new approach to investigate oscillatory brain dynamics broadly.
All data are available from the CRCNS data repository.
Recordings from hippocampal area CA1, PRE, during and POST novel spatial learningCRCNS, dx.doi.org/10.6080/K0862DC5.
Article and author information
National Institutes of Health (R01 NS109226)
- Annabelle C Singer
- Annabelle C Singer
National Science Foundation (CCF-1409422)
- Christopher Rozell
DSO National Laboratories of Singapore.
- John Lee
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Animal experimentation: All protocols were approved by the Institutional Animal Care and Use Committee of Rutgers University (hc-3) or New York University (hc-11).
- Frances K Skinner, Krembil Research Institute, University Health Network, Canada
- Received: December 11, 2018
- Accepted: July 28, 2019
- Accepted Manuscript published: July 29, 2019 (version 1)
- Version of Record published: August 6, 2019 (version 2)
© 2019, Zhang 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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