The Psychedelic State Induced by Ayahuasca Modulates the Activity and Connectivity of the Default Mode Network
Fernanda Palhano-Fontes, Kátia C. Andrade, Luís Fernando Tófoli, Antônio Carlos Dos Santos, José Alexandre S. Crippa, Jorge Hallak, Sidarta Ribeiro, Dráulio Barros de Araújo
PLoS One February 18, 2015 DOI: 10.1371/journal.pone.0118143 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 10 |
| Population | Experienced subjects |
| Intervention | Ayahuasca |
| Topics | Ayahuasca Default mode network |
| Keywords | Precuneus Posterior cingulate Hallucinogen Mind-wandering Resting State FMRI Unconsciousness |
| Citations | 461 |
| Key findings | Ayahuasca significantly decreased activity in the DMN, including the PCC/Precuneus and mPFC, and reduced functional connectivity within the PCC/Precuneus, with no significant change in DMN-TPN orthogonality. |
Abstract
The experiences induced by psychedelics share a wide variety of subjective features, related to the complex changes in perception and cognition induced by this class of drugs. A remarkable increase in introspection is at the core of these altered states of consciousness. Self-oriented mental activity has been consistently linked to the Default Mode Network (DMN), a set of brain regions more active during rest than during the execution of a goal-directed task. Here we used fMRI technique to inspect the DMN during the psychedelic state induced by Ayahuasca in ten experienced subjects. Ayahuasca is a potion traditionally used by Amazonian Amerindians composed by a mixture of compounds that increase monoaminergic transmission. In particular, we examined whether Ayahuasca changes the activity and connectivity of the DMN and the connection between the DMN and the task-positive network (TPN). Ayahuasca caused a significant decrease in activity through most parts of the DMN, including its most consistent hubs: the Posterior Cingulate Cortex (PCC)/Precuneus and the medial Prefrontal Cortex (mPFC). Functional connectivity within the PCC/Precuneus decreased after Ayahuasca intake. No significant change was observed in the DMN-TPN orthogonality. Altogether, our results support the notion that the altered state of consciousness induced by Ayahuasca, like those induced by psilocybin (another serotonergic psychedelic), meditation and sleep, is linked to the modulation of the activity and the connectivity of the DMN.
In the evidence
This study is part of the evidence base for a synthesis in the library. Here is how each one recorded it.
-
State of the evidence: Ayahuasca Supports
Ayahuasca significantly decreased activity in default mode network hubs (PCC/precuneus and mPFC) and reduced functional connectivity within the PCC/precuneus, with no significant change in DMN-task-positive network orthogonality.
Synthesized
Comparable studies
Other observational and cohort studies on default mode network, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| A default mode of brain function Normal adult human brain | 2001 | Observational study | |
| Resting-State Functional Connectivity Reflects Structural Connectivity in the Default Mode Network Healthy subjects | 2008 | Observational cohort | |
| Meditation experience is associated with increased cortical thickness Participants with extensive Insight meditation experience and matched controls | 2005 | Observational cohort | n = 20 |
| Meditation experience is associated with differences in default mode network activity and connectivity Experienced meditators and matched meditation-naive controls | 2011 | Observational cohort | |
| The precuneus/posterior cingulate cortex plays a pivotal role in the default mode network: Evidence from a partial correlation network analysis Healthy subjects | 2008 | Observational study |
Citations in the library
Cited by 341
- Neural correlates of the LSD experience revealed by multimodal neuroimaging. Proceedings of the National Academy of Sciences April 11, 2016
- Rapid antidepressant effects of the psychedelic ayahuasca in treatment-resistant depression: a randomized placebo-controlled trial Psychological Medicine June 15, 2018
- The Therapeutic Potential of Psychedelic Drugs: Past, Present, and Future. Neuropsychopharmacology April 26, 2017
- Psilocybin for treatment-resistant depression: fMRI-measured brain mechanisms. Scientific Reports October 13, 2017
- Increased Global Functional Connectivity Correlates with LSD-Induced Ego Dissolution. Current Biology April 13, 2016
and 336 more in the library
Cites 30
- A default mode of brain function Proceedings of the National Academy of Sciences January 16, 2001
- Meditation experience is associated with differences in default mode network activity and connectivity Proceedings of the National Academy of Sciences November 23, 2011
- Functional connectivity of default mode network components: Correlation, anticorrelation, and causality Human Brain Mapping January 24, 2008
- Neural correlates of the psychedelic state as determined by fMRI studies with psilocybin Proceedings of the National Academy of Sciences January 23, 2012
- Neural correlates of attentional expertise in long-term meditation practitioners Proceedings of the National Academy of Sciences June 28, 2007
and 25 more in the library