Thalamic theta phase alignment predicts human memory formation and anterior thalamic cross-frequency coupling
- Otto von Guericke University, Germany
- University of Texas at Dallas, United States
- University of California, Berkeley, United States
Abstract
Previously we reported electrophysiological evidence for a role for the anterior thalamic nucleus (ATN) in human memory formation (Sweeney-Reed et al. 2014). Theta-gamma cross-frequency coupling (CFC) predicted successful memory formation, with the involvement of gamma oscillations suggesting memory-relevant local processing in the ATN. The importance of the theta frequency range in memory processing is well-established, and phase alignment of oscillations is considered to be necessary for synaptic plasticity. We hypothesized that theta phase alignment in the ATN would be necessary for memory encoding. Further analysis of the electrophysiological data reveal that phase alignment in the theta rhythm was greater during successful compared with unsuccessful encoding, and that this alignment was correlated with the CFC. These findings support an active processing role for the ATN during memory formation.
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Ethics
Human subjects: The measurements were approved by the Ethics Commission of the Medical Faculty of the Otto-von-Guericke University, Magdeburg (application number 0308), and all participants gave written informed consent in accordance with the Helsinki Declaration of 1975, as revised in 2000 and2008. Consent to participate in our study, as well as for publication of results in an anonymized format,was obtained by the neurosurgeon at the same time as consent was obtained for the surgicalprocedure.
Copyright
© 2015, Sweeney-Reed 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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Thalamic theta phase alignment predicts human memory formation and anterior thalamic cross-frequency coupling
eLife 4:e07578.
https://doi.org/10.7554/eLife.07578
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