Neural effects and phenomenology of nondual meditation and 5-MeO-DMT in an expert meditation practitioner

Meditation and psychedelics have separately been studied as powerful tools for probing consciousness through their capacity to deconstruct the sense of self. Yet, direct empirical comparisons remain scarce, particularly in expert meditators. Here, we report for the first time a case study in which an advanced meditator and Lama from the Mahāmudrā meditation tradition engaged in a traditional style of nondual meditation, placebo, and two doses of 5-MeO-DMT (5 mg and 12 mg), while high-density EEG (hdEEG), psychometric scales, and phenomenological interviews were collected in a controlled environment.The nondual meditation practice employed and low-dose 5-MeO-DMT showed overlapping features, including timelessness, reduced labeling of sensory content, and reductions in the narrative self and thoughts. Both states were marked by increased alpha power and decreased gamma power, with cross-decoding confirming significant neural overlap driven by posterior and right frontal gamma reductions. At the same time, phenomenological and hdEEG profiles differed: nondual meditation uniquely emphasized the recognition of nonduality and clarity of mind, while low-dose 5-MeO-DMT was characterized by visual imagery. In contrast, high-dose 5-MeO-DMT produced a qualitatively distinct profile of sensory disconnection, seeing a ‘white-light’, and broad increases in gamma power.These qualitative findings indicate that while self-dissolution in this style of non-dual meditation and 5-MeO-DMT overlap in certain respects, they also diverge along specific dimensions. The hdEEG findings suggest that self-deconstruction and approximations to contentless awareness are associated with at least two distinct routes: a “saturation” route, characterized by increased neural firing (indexed by elevated gamma activity), and increased entropy, associated with experiences of spaciousness, white light, and sensory disconnection (high-dose 5-MeO); and a “subtractive” route, characterized by reduced neuronal firing, and decreased entropy, linked to drastic reductions in conceptual elaboration, and increased equanimity (nondual meditation and low-dose 5-MeO-DMT). The latter convergence points to low-dose psychedelics as a potential complement to meditative training, offering synergies that may expand both scientific understanding of consciousness and clinical applications. A promising avenue for testing this possibility would be for future studies to investigate non-dual meditation under low-dose 5-MeO-DMT.