Time-resolved Neural and Experience Dynamics of Medium- and High-dose N,N-Dimethyltryptamine
Evan Lewis-Healey, Carla Pallavicini, Federico Cavanna, Tomás Ariel D'Amelio, Laura Alethia de la Fuente, Debora Copa, S. Müller, Nicolás Bruno, Enzo Tagliazucchi, T. Bekinschtein
Journal of Cognitive Neuroscience December 30, 2025 DOI: 10.1162/jocn.a.2423 via OpenAlex
Summary
AI-generated from the abstractThe psychedelic drug DMT rapidly reorganizes conscious experience and brain activity, but the link between brain dynamics and subjective effects remains unclear. In a blinded, dose-dependent study, 19 participants received 20 mg or 40 mg of DMT. The higher dose produced more intense visual hallucinations and emotional experiences. Electroencephalography data showed that alpha power and permutation entropy best tracked moment-to-moment changes in subjective experience, while Lempel-Ziv complexity—previously thought to be a strong correlate—showed the weakest association. The findings indicate that the relationship between neural complexity and psychedelic phenomenology is less straightforward than hypothesized.
Study at a glance
| Characteristics | Repeated-measures dose-dependent study Peer reviewed |
|---|---|
| Sample size | 19 |
| Population | Human participants |
| Intervention | DMT |
| Dose | 20-mg or 40-mg |
| Duration | Two sessions |
| Keywords | Electroencephalography Neural activity Dynamics music Phenomenology philosophy Alpha rhythm |
| Citations | 4 |
| Key finding | Lempel-Ziv complexity, previously considered a robust correlate of subjective experience in psychedelic states, showed the weakest association with continuous subjective experience dimensions, while oscillatory alpha power and permutation entropy were most strongly associated. |
Abstract
N,N-dimethyltryptamine (DMT) is a fast-acting psychedelic drug that induces a radical reorganization of conscious contents and brain dynamics. However, our understanding of how brain dynamics support psychedelic-induced conscious states remains unclear. We therefore present a repeated-measures dose-dependent study of the subjective and neural dynamics induced through DMT under naturalistic conditions. Nineteen participants received either a 20-mg or a 40-mg dose of freebase DMT across two sessions in a blinded, counterbalanced order. Electroencephalography data and time-resolved measures of subjective experience (Temporal Experience Tracing) were collected. Both doses of DMT induced rapid changes in experience dimensions, with the 40-mg dose inducing more extreme visual hallucinations and emotionally intense experiences. A variety of neural features were computed on the electroencephalography data, with oscillatory alpha power and permutation entropy most strongly associated with continuous subjective experience dimensions. Strikingly, Lempel-Ziv complexity, previously hailed as a robust correlate of subjective experiences within the psychedelic state, yielded the weakest associations. These findings suggest that the relationship between neural complexity and phenomenology in psychedelic states is less clear than originally hypothesized.