Neuroscience of Consciousness
January 1, 2025
Christopher Timmermann, James W. Sanders, David Reydellet et al.
19 citations
The psychedelic 5-MeO-DMT can, in its most extreme cases, produce a complete absence of self-experience and other perceptual content while preserving a quality of aroused, waking awareness. In an exploratory observational study in naturalistic ceremonial settings, micro-phenomenological interviews, questionnaires, and EEG recordings revealed a dynamic progression of effects, including variable disruptions of bodily and narrative self, reduced phenomenal distinctions, and visual imagery. EEG showed global alpha and posterior beta power reductions, suggesting inhibition of top-down brain models. The findings indicate 5-MeO-DMT's potential as a pharmacological model for deconstructed consciousness, though retrospective questionnaires have limitations.
PsyArXiv
May 14, 2025
James W. Sanders, Raphaël Millière, Ema Demšar et al.
4 citations
preprint
Under DMT, immersive experiences and perceived presences follow a consistent structural pattern: bodily sensations arise first, then visual and auditory elements, and only after multisensory integration and 3D spatial characteristics develop do perceived sentient presences emerge. Micro-phenomenological interviews with 23 participants who received intravenous DMT (20mg) during fMRI-EEG recordings identified 125 phenomenological categories structuring immersion, including modal sensory dimensions, amodal feelings, self/world configurations, and social engagement modes. Perceived presences varied in sensory manifestation, semantic complexity, and social interaction modes. The findings advance understanding of non-ordinary states of consciousness and support future neurophenomenological research.
PsyArXiv
December 29, 2024
James W. Sanders, Raphaël Millière, Zachary G. Daily et al.
3 citations
preprint
DMT reliably produces profound experiences of immersion in other worlds and encounters with seemingly autonomous presences, but the lived qualities and unfolding of these experiences remain poorly understood. Micro-phenomenological interviews with twenty-three healthy participants who received DMT during fMRI scanning revealed rich dimensions of immersive experience—from multisensory engagement to radical reconfigurations of self and world—and illuminated varied ways presences can be seen, felt, or otherwise sensed. The analysis identified structural features and temporal dynamics, particularly the layering of sensory effects followed by spatial, self-related, and social effects, extending beyond traditional constructs like ego dissolution or mystical experience. This mapping advances understanding of DMT's effects and conscious experience, inviting comparisons with meditation, lucid dreaming, and presence phenomena in lab-induced hallucinations or Parkinson's disease.
Neuroscience of Consciousness
January 1, 2026
James W. Sanders, Raphaël Millière, Ema Demšar et al.
The psychedelic compound DMT induces highly immersive experiences that often include encounters with seemingly sentient presences. Using micro-phenomenology, immersion under DMT was characterized as a structured continuum from subtle to gross forms. Twenty-three participants received 20 mg intravenous DMT during fMRI-EEG, followed by detailed interviews. Analysis yielded 125 phenomenological categories describing structural dimensions like sensory faculties, spatial organization, and self-world configuration. Bodily effects typically preceded visual and auditory ones, and perceived presences emerged only after multisensory integration and 3D spatial characteristics had developed, illustrating a hierarchical relationship between subtle and gross immersion. Perceived presences varied widely in sensory modality, semantic complexity, and relational mode, showing immersion as a dynamic, constructive process.