DMT alters cortical travelling waves

  1. Andrea Alamia  Is a corresponding author
  2. Christopher Timmermann
  3. Rufin VanRullen
  4. Robin L Carhart-Harris
  1. CNRS - Université de Toulouse, France
  2. Imperial College London, United Kingdom
  3. CNRS, UMR5549, Centre de Recherche Cerveau et Cognition, Faculté de Médecine de Purpan, France

Abstract

Psychedelic drugs are potent modulators of conscious states and therefore powerful tools for investigating their neurobiology. N,N, Dimethyltryptamine (DMT) can rapidly induce an extremely immersive state of consciousness characterized by vivid and elaborate visual imagery. Here, we investigated the electrophysiological correlates of the DMT induced altered state from a pool of participants receiving DMT and (separately) placebo (saline) while instructed to keep their eyes closed. Consistent with our hypotheses, results revealed a spatio-temporal pattern of cortical activation (i.e., travelling waves) similar to that elicited by visual stimulation. Moreover, the typical top-down alpha-band rhythms of closed-eyes rest were significantly decreased, while the bottom-up forward wave was significantly increased. These results support a recent model proposing that psychedelics reduce the 'precision-weighting of priors', thus altering the balance of top-down versus bottom-up information passing. The robust hypothesis-confirming nature of these findings imply the discovery of an important mechanistic principle underpinning psychedelic-induced altered states.

Data availability

The data and the code to perform the analysis are available at : https://osf.io/wujgp/

The following data sets were generated

Article and author information

Author details

  1. Andrea Alamia

    CerCo, CNRS - Université de Toulouse, Toulouse, France
    For correspondence
    andrea.alamia@cnrs.fr
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-9826-2161
  2. Christopher Timmermann

    Medicine, Imperial College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-2281-377X
  3. Rufin VanRullen

    CNRS, CNRS, UMR5549, Centre de Recherche Cerveau et Cognition, Faculté de Médecine de Purpan, Toulouse, France
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-3611-7716
  4. Robin L Carhart-Harris

    Psychedelic Research Group, Centre for Psychiatry, Division of Brain Sciences, Imperial College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.

Funding

Alex Mosley Charitable Trust

  • Robin L Carhart-Harris

Ad Astra Chandaria Foundation

  • Robin L Carhart-Harris

CRCNS ANR-NSF (ANR-19-NEUC-0004)

  • Rufin VanRullen

Comision Nacional de Investigacion Cientifica y Tecnologica de Chile

  • Christopher Timmermann

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

Ethics

Human subjects: All participants provided written informed consent, and the study was approved by the National Research Ethics (NRES) Committee London - Brent and the Health Research Authority (16/LO/0897). The study was conducted in line with the Declaration of Helsinki and the National Health Service Research Governance Framework.

Copyright

© 2020, Alamia 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. Andrea Alamia
  2. Christopher Timmermann
  3. Rufin VanRullen
  4. Robin L Carhart-Harris
(2020)
DMT alters cortical travelling waves
eLife 9:e59784.
https://doi.org/10.7554/eLife.59784

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https://doi.org/10.7554/eLife.59784

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