Exploring 5-MeO-DMT as a pharmacological model for deconstructed consciousness

Psychedelics offer a means to perturb conscious experience while preserving wakefulness, making them useful for studying mechanisms of consciousness. Timmermann and colleagues note that 5-MeO-DMT is pharmacologically atypical among classic psychedelics: although it acts at 5-HT2A receptors, preliminary reports point to unusually rapid and potent disruption of self-related processing with comparatively less visual imagery, possibly related to higher 5-HT1A agonism. Anecdotal reports describe peak 5-MeO-DMT states as a ‘‘void’’ or ‘‘nondual’’ experience in which selfhood and ordinary phenomenal contents are profoundly diminished despite preserved arousal, a profile that could be informative about the minimal constituents of subjectivity or a ‘‘minimal phenomenal experience.’' This study set out to perform an exploratory neurophenomenological investigation of 5-MeO-DMT in naturalistic ceremonial settings. The investigators combined micro-phenomenological interviews (MPIs), retrospective psychometric questionnaires (the Altered States of Consciousness, ASC, questionnaire), and electroencephalography (EEG) to characterise time-dependent phenomenology and concurrent brain activity. The primary hypothesis was that 5-MeO-DMT would disrupt multiple aspects of the sense of self and reduce alpha-band power in EEG. The paper emphasises the need for rigorous first-person methods (MPIs) to mitigate confabulation and improve the temporal precision of subjective reports when studying extreme psychedelic states.

This was an observational, naturalistic study recruiting adults who intended to participate in 5-MeO-DMT ceremonies in the Netherlands or Spain. Eligibility required being 18 years or older and understanding English; ethics approvals were obtained and all participants provided informed consent. The research team did not organise or administer the ceremonies. Inhalation (via pipe) was the route of ingestion; some participants received synthetic 5-MeO-DMT (Netherlands) and others inhaled parotoid gland secretions from Incilius alvarius (Spain). Facilitators determined doses; reported average doses were 15.4 mg for the Netherlands ceremony and 28.7 mg for the Spain ceremony. The extracted text reports a sample of 14 participants (5 females, 8 males; mean age 35.8 ± 11.8) and notes that some demographic items were incomplete for a minority of participants. Phenomenological data were collected using micro-phenomenological interviews conducted immediately after participants returned to baseline. Interviews (approximately 30–60 minutes) were audio-recorded, transcribed, and analysed by combining micro-phenomenological parsing into time-ordered phases with thematic clustering across participants to identify recurrent experiential substates and their transitions. The ASC questionnaire was administered after the MPI as a complementary retrospective measure. EEG was recorded continuously from a baseline 5-minute period and for up to 15 minutes during and after administration using a 24-channel wireless cap with 21 dry electrodes (300 Hz sampling). Recordings were made with eyes closed while participants were seated. Preprocessing included demean, bandpass filtering (1–30 Hz), visual inspection to remove gross artefacts, and Independent Component Analysis to remove ECG and ocular components. Five participants were excluded from EEG analysis due to unusable data. Spectral analysis used Hanning-windowed FFTs between 1 and 30 Hz at 0.5 Hz resolution, with averaging into canonical bands (including alpha and beta), and gamma/entropy metrics were not analysed because of susceptibility to muscle artefact. Statistical comparisons used cluster-based t-statistics comparing the 5-minute post-administration window against the 5-minute baseline. Given sample size and variability, a qualitative neurophenomenological inspection compared z-scored spectral changes for participants who reported complete absence of self-related features versus those who retained some self-features; however, no real-time experience sampling was performed to align specific phenomenology with moment-to-moment EEG changes.

Phenomenology: Micro-phenomenological analysis identified six recurring experiential categories visited by subsets of participants: Onset (reported by 86%), Immersion/Merging (43%), Abstract (43%), Everything/Nothing (29%), Reconstitution (57%), and Afterglow (43%). The Onset phase was rapid and described with dynamic verbs (e.g. 'shattering', 'collapsing') affecting body, perception, thought, or self. Immersion/Merging involved reduced awareness of surroundings and intense, sometimes depersonalised feelings. The Abstract category described a disembodied state with elementary visuospatial form but lacking ordinary spatial, temporal, and reflective qualities. Everything/Nothing denoted extreme reduction of phenomenological distinctions, absence of subject–object structure, and paradoxical reports of both fullness and void. Reconstitution traced a gradual, variable return of sensory and narrative structures, and Afterglow described a near-baseline but clearer, peaceful state for some participants. Memory effects—difficulty or impossibility of recalling peak moments—were reported and were temporally associated with peak phases; these effects occurred exclusively among participants from the Spain ceremony (63%), who received higher average doses, suggesting amnesia could have led to underreporting of some peak categories. Questionnaire: ASC scores were highly variable across participants. Notably, mean scores on the Oceanic Boundlessness subscale were on average higher in the Netherlands ceremony (71.3%) than the Spain ceremony (58.7%), yet MPIs indicated more frequent peak experiences in the Spain ceremony; the authors attribute this divergence to the limited temporal precision of static self-report questionnaires and potential contextual differences between ceremonies. EEG: Compared to baseline, administration of 5-MeO-DMT was associated with a global reduction in alpha-band power (reported maximum t[9] = 3.77, P = .0001, cluster-corrected) and posterior decreases in both low and high beta power (cluster-corrected P-values reported as .007 for low beta and max t[9] = 3.18, P = .021 for high beta). The extracted text states that five participants were removed from EEG analyses due to unusable data; the final EEG sample size is not clearly stated in the extracted material although t-statistics with df = 9 are reported. Gamma-band power and entropy measures were not analysed because of susceptibility to muscle artefact. Neurophenomenology: A qualitative comparison of averaged EEG spectra for participants who reported complete absence of self-related features (the 'abstract' or 'everything/nothing' categories) versus those who retained some self-features showed no overt differences. The investigators emphasise that absence of real-time experience sampling and use of averaged EEG across the whole period limited the ability to link specific phenomenological phases to momentary neural changes.

Timmermann and colleagues interpret their findings as preliminary support for the utility of 5-MeO-DMT as a pharmacological model of deconstructed consciousness. Peak experiences sometimes produced profound loss of narrative and embodied selfhood and severely reduced phenomenal distinctions while wakefulness was preserved, consistent with the target ‘‘deconstructed’’ states. However, such states occurred only in a subset of participants and were transient, implying variability in individual trajectories. EEG results of broad alpha suppression and posterior beta reductions are discussed in the context of prior work: reductions in alpha have been linked to diminished top-down influence of high-level models (including self-related models), and decreases in posterior beta have been associated with bodily self-disruption in related compounds and advanced meditation. The authors note that variability across other frequency bands parallels inconsistent findings in the psychedelic literature and may reflect differences in phenomenology, drug formulation, dose, or setting. They propose that linking momentary phenomenology to neural signals will require temporally guided, neurophenomenological analyses with real-time experience sampling and tighter experimental control. Key limitations acknowledged by the authors include the naturalistic, uncontrolled design, small sample size, lack of real-time experience sampling, potential amnesic effects (which could underreport peak states), and the pooling of synthetic and natural sources of 5-MeO-DMT in EEG analyses. Entropy measures were not examined because of concerns about uncontrolled artefacts; nonetheless, the authors speculate (as a hypothesis to be tested) that phenomenologically ‘‘deconstructed’’ states might correspond to increases in neuronal entropy rather than decreases. They recommend future controlled laboratory studies with larger samples, real-time phenomenological sampling, and careful control of physiological artefacts to validate the phenomenological categories and to map the neural correlates of deconstructed conscious states more precisely.