Phase-tuned neuronal firing encodes human contextual representations for navigational goals
We previously demonstrated that the phase of oscillations modulates neural activity representing categorical information using human intracranial recordings and high-frequency activity from local field potentials (Watrous et al., 2015b). We extend these findings here using human single-neuron recordings during a navigation task. We identify neurons in the medial temporal lobe with firing-rate modulations for specific navigational goals, as well as for navigational planning and goal arrival. Going beyond this work, using a novel oscillation detection algorithm, we identify phase-locked neural firing that encodes information about a person's prospective navigational goal in the absence of firing rate changes. These results provide evidence for navigational planning and contextual accounts of human MTL function at the single-neuron level. More generally, our findings identify phase-coded neuronal firing as a component of the human neural code.
The human single neuron recordings raw data can be obtained upon request from Joshua Jacobs (email@example.com). At this point, the raw data has not been made publicly available to ensure controlled access to the dataset and that the patients' anonymity is not compromised.
Simultaneous electrophysiological recordings of ensembles of isolated neurons in rat medial prefrontal cortex and intermediate CA1 area of the hippocampus during a working memory taskPublicly available at CRCNS.org. - Collaborative Research in Computational Neuroscience.
Article and author information
National Institute of Neurological Disorders and Stroke (NS033221)
- Itzhak Fried
National Institute of Neurological Disorders and Stroke (NS084017)
- Itzhak Fried
National Institute of Mental Health (MH104606)
- Joshua Jacobs
National Science Foundation (DGE 16-44869)
- Salman E Qasim
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Human subjects: The Medical Institutional Review Board at the University of California-Los Angeles approved this study (IRB#10-000973) involving recordings from patients with drug-resistant epilepsy who provided informed consent to participate in research.
- Timothy E Behrens, University of Oxford, United Kingdom
- Received: October 12, 2017
- Accepted: June 21, 2018
- Accepted Manuscript published: June 22, 2018 (version 1)
- Version of Record published: July 11, 2018 (version 2)
© 2018, 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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