Healthy VolunteersNeuroimaging & Brain MeasuresDepressive DisordersAyahuasca

Subacute Effects of the Psychedelic Ayahuasca on the Salience and Default Mode Networks

In a randomised placebo-controlled trial, 24 hours after a single ayahuasca session healthy participants showed increased anterior cingulate connectivity within the salience network, reduced posterior cingulate connectivity within the default mode network and strengthened salience–default mode coupling, with no change in primary sensory networks. These subacute network shifts correlated with acute subjective effects (somesthesia, volition and affect), suggesting ayahuasca transiently modulates higher-order interoceptive, affective and self‑referential brain systems.

Authors

  • Fernanda Palhano-Fontes
  • Draulio Araújo

Published

Journal of Psychopharmacology
individual Study

Abstract

Background

Neuroimaging studies have just begun to explore the acute effects of psychedelics on large-scale brain networks’ functional organization. Even less is known about the neural correlates of subacute effects taking place days after the psychedelic experience. This study explores the subacute changes of primary sensory brain networks and networks supporting higher-order affective and self-referential functions 24 hours after a single session with the psychedelic ayahuasca.

Methods

We leveraged task-free functional magnetic resonance imaging data 1 day before and 1 day after a randomized placebo-controlled trial exploring the effects of ayahuasca in naïve healthy participants (21 placebo/22 ayahuasca). We derived intra- and inter-network functional connectivity of the salience, default mode, visual, and sensorimotor networks, and assessed post-session connectivity changes between the ayahuasca and placebo groups. Connectivity changes were associated with Hallucinogen Rating Scale scores assessed during the acute effects.

Results

Our findings revealed increased anterior cingulate cortex connectivity within the salience network, decreased posterior cingulate cortex connectivity within the default mode network, and increased connectivity between the salience and default mode networks 1 day after the session in the ayahuasca group compared to placebo. Connectivity of primary sensory networks did not differ between groups. Salience network connectivity increases correlated with altered somesthesia scores, decreased default mode network connectivity correlated with altered volition scores, and increased salience default mode network connectivity correlated with altered affect scores.

Conclusion

These findings provide preliminary evidence for subacute functional changes induced by the psychedelic ayahuasca on higher-order cognitive brain networks that support interoceptive, affective, and self-referential functions.

Available with Blossom Pro

Research Summary of 'Subacute Effects of the Psychedelic Ayahuasca on the Salience and Default Mode Networks'

Introduction

Classic psychedelics produce altered states of consciousness with wide-ranging effects on sensory, cognitive, autonomic, interoceptive, self-referential, and emotional systems. Ayahuasca is a traditional Amazonian admixture containing N,N-dimethyltryptamine (N,N-DMT) and monoamine oxidase inhibitors; N,N-DMT has high affinity for serotonergic and sigma-1 receptors, while the monoamine oxidase inhibitors render it orally active. Recent clinical trials have reported rapid antidepressant effects of ayahuasca, including benefits observed 1 day after a single session, but the neural mechanisms underlying changes in affect, mood, and self-representation remain incompletely understood. Task-free functional MRI (tf-fMRI) can map intrinsic large-scale brain networks such as the salience network (involving the anterior cingulate cortex and anterior insula) and the default mode network (involving posterior cingulate cortex, precuneus, medial prefrontal cortex), which are implicated in interoception, socioemotional processing, and self-referential thought. Pasquini and colleagues set out to characterise subacute (24-hour) changes in intra- and inter-network functional connectivity after a single ayahuasca session in ayahuasca‑naïve healthy participants, and to relate those changes to subjective measures of the acute psychedelic experience. The primary hypothesis was that 24 hours after dosing ayahuasca would alter higher-order affective and self-referential networks (salience and default mode) but not primary sensory networks. The investigators used a seed-based connectivity approach, complemented by independent component analysis (ICA), to map salience, default mode, visual and sensorimotor networks before and 24 hours after dosing in a randomised placebo-controlled design.

Expert Research Summaries

Go Pro to access AI-powered section-by-section summaries, editorial takes, and the full research toolkit.

Full Text PDF

Full Paper PDF

Create a free account to open full-text PDFs.

Study Details

References (29)

Papers cited by this study that are also in Blossom

Ketamine Treatment and Global Brain Connectivity in Major Depression

Abdallah, C. G., Averill, L. A., Collins, K. A. et al. · Neuropsychopharmacology (2016)

Neural correlates of the psychedelic state as determined by fMRI studies with psilocybin

Carhart-Harris, R. L., Erritzoe, D., Williams, T. et al. · PNAS (2012)

Functional connectivity measures after psilocybin inform a novel hypothesis of early psychosis

Carhart-Harris, R. L., Leech, R., Erritzoe, D. et al. · Schizophrenia Bulletin (2012)

241 cited
Neural correlates of the LSD experience revealed by multimodal neuroimaging

Carhart-Harris, R. L., Muthukumaraswamy, S., Roseman, L. et al. · PNAS (2016)

Psilocybin for treatment-resistant depression: fMRI-measured brain mechanisms

Carhart-Harris, R. L., Roseman, L., Bolstridge, M. et al. · Scientific Reports (2017)

Seeing with the eyes shut: Neural basis of enhanced imagery following ayahuasca ingestion

De Araujo, D. B., Ribeiro, S., Cecchi, G. A. et al. · Human Brain Mapping (2011)

Pilot study of psilocybin treatment for anxiety in patients with advanced-stage cancer

Grob, C. S., Danforth, A. L., Chopra, G. S. et al. · JAMA Psychiatry (2011)

Show all 29 references
Distinct acute effects of LSD, MDMA, and D-amphetamine in healthy subjects.

Holze, F., Vizeli, P., Müller, F. et al. · Neuropsychopharmacology (2019)

214 cited
Ketamine-Associated Brain Changes: A Review of the Neuroimaging Literature

Ionescu, D. F., Felicione, J. M., Gosai, A. et al. · Harvard Review of Psychiatry (2018)

LSD-induced entropic brain activity predicts subsequent personality change

Lebedev, A. V., Kaelen, M., L€ Ovd En, M. et al. · Human Brain Mapping (2016)

292 cited
Finding the self by losing the self: Neural correlates of ego-dissolution under psilocybin

Lebedev, A. V., L€ Ovd En, M., Rosenthal, G. et al. · Human Brain Mapping (2015)

Antidepressant effects of a single dose of ayahuasca in patients with recurrent depression: a preliminary report

Osório, F. L., Sanches, R. F., Macedo, L. et al. · brazilian Journal of Psychiatry (2015)

420 cited
The psychedelic state induced by ayahuasca modulates the activity and connectivity of the default mode network

Palhano-Fontes, F., Andrade, K. C., Tófoli, L.F. et al. · PLOS ONE (2015)

The effects of psilocybin and MDMA on between-network resting state functional connectivity in healthy volunteers

Roseman, L., Leech, R., Feilding, A. et al. · Frontiers in Human Neuroscience (2014)

229 cited
Antidepressant effects of a single dose of ayahuasca in patients with recurrent depression a SPECT study

Sanches, R. F., Osório, F. L., Dos Santos, R. G. et al. · Journal of Clinical Psychopharmacology (2016)

380 cited
Increased global functional connectivity correlates with LSD-induced ego dissolution

Tagliazucchi, E., Roseman, L., Kaelen, M. et al. · Current Biology (2016)

Changes in Spirituality Among Ayahuasca Ceremony Novice Participants

Trichter, S., Klimo, J., Krippner, S. · Journal of Psychoactive Drugs (2009)

75 cited
Shannon entropy of brain functional complex networks under the influence of the psychedelic Ayahuasca

Viol, A., Palhano-Fontes, F., Onias, H. et al. · Scientific Reports (2017)

Cited By (31)

Papers in Blossom that reference this study

Predicting and exploring ayahuasca effects: Perception, mind-wandering, and EEG oscillations

Silva-Costa, N., Pessoa, J. A., Andrade, K. C. et al. · Journal of Psychopharmacology (2025)

Reduced Brain Responsiveness to Emotional Stimuli With Escitalopram But Not Psilocybin Therapy for Depression

Wall, M. B., Demetriou, L., Giribaldi, B. et al. · American Journal of Psychiatry (2025)

Human brain changes after first psilocybin use

Lyons, T., Spriggs, M. J., Kerkelä, L. et al. · Biorxiv (2024)

Predicting the outcome of psilocybin treatment for depression from baseline fMRI functional connectivity

Copa, D., Erritzoe, D., Giribaldi, B. et al. · Journal of Affective Disorders (2024)

Exploring mechanisms of psychedelic action using neuroimaging

Erritzoe, D., Timmermann, C., Godfrey, K. et al. · Nature Mental Health (2024)

28 cited
Psychedelics for acquired brain injury: a review of molecular mechanisms and therapeutic potential

Allen, J., Dames, S., Foldi, C. J. et al. · Molecular Psychiatry (2024)

Show all 31 papers
Cortical structural differences following repeated ayahuasca use hold molecular signatures

Mallaroni, P., Mason, N. L., Kloft, L. et al. · Frontiers in Neuroscience (2023)

6 cited
N, N-Dimethyltryptamine (DMT)-Occasioned Familiarity and the Sense of Familiarity Questionnaire (SOF-Q)

Lawrence, D. W., Timmermann, C. · Journal of Psychoactive Drugs (2023)

The Altered States Database: Psychometric data from a systematic literature review

Prugger, J., Derdiyok, E., Dinkelacker, J. et al. · Scientific Data (2022)

Default Mode Network Modulation by Psychedelics: A Systematic Review

Gattuso, J. J., Perkins, D., Ruffell, S. G. D. et al. · International Journal of Neuropsychopharmacology (2022)

Nootropic effects of LSD: Behavioral, molecular and computational evidence

Ornelas, I. M., Cini, F. A., Wießner, I. et al. · Experimental Neurology (2022)

25 cited
Psychedelic Resting-state Neuroimaging: A Review and Perspective on Balancing Replication and Novel Analyses

McCulloch, D. E-W., Knudsen, G. M., Barrett, F. S. et al. · Neuroscience and Biobehavioral Reviews (2022)

Increased global integration in the brain after psilocybin therapy for depression

Daws, R. E., Timmermann, C., Giribaldi, B. et al. · Nature Medicine (2022)

Psychedelic-Assisted Therapy for Substance Use Disorders and Potential Mechanisms of Action

Rieser, N. M., Herdener, M. ;., Preller, K. H. · Current Topics in Behavioral Neurosciences (2021)

Psilocybin therapy increases cognitive and neural flexibility in patients with major depressive disorder

Doss, M. K., Považan, M., Rosenberg, M. D. et al. · Translational Psychiatry (2021)

249 cited
Psychedelics as Novel Therapeutics in Alzheimer’s Disease: Rationale and Potential Mechanisms

Garcia-Romeu, A., Darcy, S., Jackson, H. et al. · Current Topics in Behavioral Neurosciences (2021)

Prefrontal contributions to the stability and variability of thought and conscious experience

Zamani, A., Carhart-Harris, R. L., Christoff, K. · Neuropsychopharmacology (2021)

Decreased brain modularity after psilocybin therapy for depression

Daws, R. E., Timmermann, C., Giribaldi, B. et al. · Research Square (2021)

Protocol for Outcome Evaluation of Ayahuasca-Assisted Addiction Treatment: The Case of Takiwasi Center

Rush, B., Marcus, O., García, S. et al. · Frontiers in Pharmacology (2021)

19 cited
Spontaneous and deliberate creative cognition during and after psilocybin exposure

Mason, N. L., Kuypers, K. P. C., Reckweg, J. T. et al. · Translational Psychiatry (2021)

86 cited
Hallucinogenic/psychedelic 5HT2A receptor agonists as rapid antidepressant therapeutics: Evidence and mechanisms of action

Dos Santos, R. G., Hallak, J. E., Baker, G. et al. · Journal of Psychopharmacology (2021)

Combining Psychedelic and Mindfulness Interventions: Synergies to Inform Clinical Practice

Payne, J. E., Chambers, R., Liknaitzky, P. · ACS Pharmacology and Translational Science (2021)

55 cited
Lasting effects of a single psilocybin dose on resting-state functional connectivity in healthy individuals

McCulloch, D. E-W., Madsen, M. K., Stenbæk, D. S. et al. · Journal of Psychopharmacology (2021)

The History of Psychedelics in Psychiatry

Nichols, D. E., Walter, H. · Pharmacopsychiatry (2020)

Pivotal Mental States

Brouwer, A., Carhart-Harris, R. L. · Journal of Psychopharmacology (2020)

Your Personal Research Library

Go Pro to save papers, add notes, rate studies, and organize your research into custom shelves.

Subacute Effects of the Psychedelic Ayahuasca on... — Research Summary & Context | Blossom