A November 2025 study in Communications Biology found that seven days of meditation in a San Diego retreat sharply reduced default mode network connectivity. The same program also raised mystical-experience scores to a level the lead researcher said was comparable to psilocybin.
San Diego retreat scans
Researchers scanned twenty adults before and after the seven-day residential program. The retreat combined lectures, guided meditation and group practices, and no substances were involved at any point.
By the end of the week, the brain network linked to constant self-commentary had gone quiet enough to produce a change the study described as sharp and significant. The report says that pattern appeared after the retreat, not during a drug intervention.
Vipassana silence and day four
The retreat leaned heavily on Vipassana-style silent meditation. The study says the first two days were the loudest inside the narrator's mind, and by day four meals had stopped being something people talked through.
That detail points to the setting as well as the practice. The article says the work was observational and had no separate control group, so it cannot split the effect of meditation from the retreat format, isolation, routine or the absence of a phone.
Communications Biology findings
The study's standard measure of mystical or ego-dissolving experience is the scale used to compare a change in subjective state. On that measure, the retreat scores rose to a level the lead researcher described as comparable to what typically requires psilocybin.
For readers thinking about the practical takeaway, the result is not a treatment protocol or a drug substitute backed by a trial design. It is a measured before-and-after finding from twenty adults in San Diego, and the next question is how much of the change came from meditation itself rather than the retreat environment around it.
