A growing body of research has suggested that meditation and psychedelic medicines may share more in common than previously believed. Now, a new study from researchers at the University of California San Diego provides fresh evidence that intensive meditation may induce measurable biological changes across the brain and body, including patterns of neural connectivity that resemble those previously observed following psychedelic experiences.
Published in Communications Biology, the observational study examined 20 healthy adults who participated in a seven-day residential mind-body retreat. Participants completed approximately 33 hours of guided meditation alongside lectures, reconceptualisation exercises and group healing practices before undergoing brain imaging and extensive blood analysis.
While the findings do not establish that meditation produces the same biological effects as psilocybin or other psychedelic medicines, they suggest that profound altered states of consciousness may arise through multiple pathways — some pharmacological and others entirely non-drug based.
The researchers’ findings raise an intriguing question for psychedelic science: could some of the brain and biological changes associated with psychedelic experiences also be reached through intensive contemplative practice?
A Whole-Body Response
Rather than focusing solely on psychological outcomes, the research team examined a broad range of biological markers.
Functional MRI scans revealed changes in brain connectivity, particularly within networks associated with self-referential thinking and internal mental activity.
Researchers observed reduced connectivity within the default mode network and salience network, alongside changes in whole-brain organisation and integration. These findings are particularly interesting because changes to the default mode network and increased communication between normally distinct brain networks have become recurring observations in psychedelic neuroimaging research.
The biological effects extended well beyond the brain.
Blood samples collected after the retreat demonstrated measurable changes in immune signalling, metabolism and molecular pathways associated with brain function. Researchers also observed changes involving endogenous opioid signalling and inflammatory pathways.
Laboratory experiments provided another intriguing result.
When researchers exposed cultured neurons to blood plasma collected after the retreat, the neurons demonstrated greater neurite outgrowth than those exposed to pre-retreat samples. Neurites are the branches that extend from neurons and are involved in forming connections with other cells.
The result provides evidence consistent with changes in processes associated with neuroplasticity, although it does not demonstrate that participants themselves experienced increased neuroplasticity in their brains.
Taken together, the findings suggest that intensive contemplative practice may trigger coordinated changes across multiple biological systems simultaneously.
Mystical Experiences Without Psychedelics
Perhaps the most intriguing finding involved the participants’ subjective experiences.
Using the Mystical Experience Questionnaire (MEQ-30), researchers found significant increases in reported feelings of unity, transcendence and altered consciousness following the retreat.
Average MEQ scores increased from 2.37 before the retreat to 3.02 afterwards.
Importantly, participants reporting stronger mystical experiences also showed relationships between the intensity of those experiences and changes in several biological and neural measures.
This is particularly relevant to psychedelic research.
Mystical-type experiences have become one of the most closely studied aspects of psychedelic states. Research involving psilocybin and other psychedelics has suggested that profound experiences of unity, transcendence and interconnectedness may be associated with subsequent psychological benefits.
The UC San Diego findings raise the possibility that these experiences are not exclusive to psychedelic drugs.
According to the authors, the neural signatures observed during the retreat bear similarities to those reported in previous neuroimaging studies involving psilocybin.
Senior author Professor Hemal Patel said the researchers were observing “the same mystical experiences and neural connectivity patterns that typically require psilocybin, now achieved through meditation practice alone.”
That comparison is likely to attract considerable attention across both contemplative neuroscience and psychedelic medicine.
It also raises a deeper question: are some of the effects attributed to psychedelics actually properties of the altered state of consciousness itself, rather than the drug alone?
Meditation and Psychedelics May Take Different Routes to Similar States
The findings do not suggest that meditation and psychedelics work in the same way.
Psilocybin produces profound changes in consciousness through its interaction with the brain’s serotonin system, particularly the 5-HT2A receptor. Meditation does not operate through the same pharmacological mechanism.
Yet the brain may have multiple ways of reaching certain functional states.
Psychedelics have been associated with reduced rigidity within established brain networks, changes in self-processing and increased communication between systems that do not normally interact as strongly.
Intensive meditation appears capable of producing at least some superficially similar changes.
That does not mean the experiences are identical.
Rather, it suggests that the human brain may have multiple routes towards states characterised by altered self-awareness, reduced habitual thinking and increased integration between normally distinct neural systems.
For psychedelic researchers, that distinction could become increasingly important.
If the therapeutic potential of psychedelics partly depends on changes in consciousness, rather than solely on the pharmacological action of the drug, then researchers may eventually be able to investigate those mechanisms across a much broader range of interventions.
Important Limitations
Despite the exciting results, the study has significant limitations that should temper the strongest interpretations.
The research involved only 20 healthy volunteers and did not include a matched control group.
It was also an observational study of a complex retreat rather than a controlled experiment testing meditation in isolation.
Participants undertook approximately 33 hours of guided meditation, but the retreat also included lectures, reconceptualisation exercises and group healing practices incorporating open-label placebo techniques.
Because these elements were delivered together, researchers cannot determine which component was responsible for the observed changes.
The participants were also a highly selected group taking part in an intensive residential programme, meaning the findings may not generalise to people practising meditation under ordinary conditions.
The study also cannot establish whether the observed biological changes persist beyond the retreat or whether they would occur in people with depression, PTSD, addiction or other clinical conditions.
There is also relevant context surrounding the retreat itself. Neuroscience educator Joe Dispenza, whose organisation hosted the programme, was involved in the retreat and is among the study’s authors. The researchers disclosed these relationships in the published paper.
In July 2026, Communications Biology also published an author correction clarifying aspects of the study’s description and methodology.
None of these limitations invalidate the findings, but they reinforce the need to treat the research as an intriguing early observation rather than proof that meditation can reproduce psychedelic effects.
Randomised controlled trials will be needed before the findings can be translated into therapeutic applications.
Implications for Psychedelic Medicine
For the psychedelic field, the study contributes to an increasingly important discussion.
Rather than viewing psychedelics as unique producers of mystical experience, researchers are beginning to investigate whether altered states themselves may represent a therapeutic mechanism, regardless of how they are achieved.
If meditation, breathwork and psychedelic medicines can all influence overlapping neural processes associated with neuroplasticity, emotional flexibility and changes in self-processing, future treatments may increasingly combine pharmacological and non-pharmacological approaches.
Indeed, mindfulness and meditation practices are already incorporated into various psychedelic-assisted therapy models, particularly during preparation and integration.
The new findings suggest those complementary techniques may not simply support psychedelic therapy.
They may also activate some of the biological and neural processes that psychedelic researchers are trying to understand.
That could eventually lead to new therapeutic approaches that combine pharmacological and contemplative interventions — or, in some circumstances, explore whether particular therapeutic outcomes can be achieved without psychedelic drugs at all.
A New Direction for Consciousness Research
The study also reflects a broader shift occurring within neuroscience.
For decades, meditation research focused largely on stress reduction, attention and psychological wellbeing. Modern neuroscience is increasingly examining whether conscious experience itself can influence measurable biological systems, including immune regulation, metabolism and processes associated with brain plasticity.
The UC San Diego study takes that idea considerably further by examining the relationship between subjective experience and changes occurring throughout the body.
Although many questions remain unanswered, the findings suggest that profound changes in conscious experience can coincide with detectable biological changes — even in the absence of a psychoactive drug.
That does not mean meditation and psychedelics are interchangeable.
Nor does it mean that meditation has been shown to replicate the therapeutic effects of psilocybin.
But it does suggest that the psychedelic experience may be part of a much larger scientific question.
How many different ways can we change the brain’s patterns of perception, self-processing and connectivity — and what happens when we do?
Psychedelic medicines may represent one particularly powerful route into these states.
Intensive meditation may represent another.
Future research will need to determine how much these pathways genuinely have in common.
For now, the UC San Diego study provides another intriguing reminder that the boundaries between meditation, consciousness research and psychedelic science may be far more interconnected than previously imagined.
Reference
Jinich-Diamant A. et al. “Neural and molecular changes during a mind-body reconceptualization, meditation, and open label placebo healing retreat: an observational study.” Communications Biology (2025).
