This secondary analysis of an RCT brain imaging (EEG) study (n=30) examines how DMT/HAR and Harmine alone affect face recognition and self-processing in healthy males using a visual oddball task. It finds DMT/HAR enhanced early visual processing while reducing neural differentiation between self and other faces at posterior sites, suggesting psychedelics reshape rather than erase self-boundaries while preserving socially meaningful representations.
Abstract of Ayahuasca-Inspired DMT/HAR Formulation Reduces Brain Differentiation Between Self and Other Faces
“Background Psychedelics are known to profoundly alter perception and self-referential processing, yet their specific effects on face recognition —particularly regarding recognition of face familiarity—remain underexplored.
Objective This study investigates the effects of an ayahuasca-inspired novel DMT/HAR (N,N-dimethyltryptamine/Harmine) formulation and Harmine alone on face recognition and self-referential processing, as measured by event-related potentials (ERPs) and subjective behavioral measures.
Methods In a within-subject, double-blind, placebo-controlled design, 30 healthy male participants underwent EEG recording during a visual oddball task involving Self, Familiar, and Unknown Faces. The study compared the effects of a DMT/HAR formulation, harmine alone, and placebo on key visual ERP components: P1, N170, and P300.
Results DMT/HAR enhanced early visual processing (P1) but attenuated structural encoding (N170) across all face categories, suggesting altered perceptual integration. Crucially, DMT/HAR selectively reduced P300 amplitudes for self-faces, blurring the neural differentiation between self-other faces at posterior sites. Concurrently, frontal electrodes showed increased self-face responses and decreased unknown-face responses, indicating a dynamic reorganization of self-referential salience rather than a general dissolution of self-boundaries. Familiar face processing remained stable across conditions, suggesting that socially meaningful representations were preserved despite psychedelic-induced perceptions shifts.
Conclusion These findings reveal that psychedelics reshape self-referential processing by balancing perceptual instability with compensatory cognitive mechanisms, leading to a restructuring rather than an erasure of self-boundaries. This reorganization of self-salience may underlie the therapeutic effects of psychedelics in disorders characterized by rigid self-processing, such as depression and social anxiety. By reducing neural differentiation between self and others, psychedelics may facilitate flexibility in social and emotional processing, offering new insights into their potential clinical applications.”
Authors: Dila Suay, Helena D. Aicher, Micheal Kometer, Michael J. Mueller, Luzia Caflisch, Alexandra Hempe, Camilla P. Steinhart, Claudius Elsner, Ilhui A. Wicki, Jovin Müller, Daniel Meling, Dario A. Dornbierer, Milan Scheidegger & Davide Bottari
Summary of Ayahuasca-Inspired DMT/HAR Formulation Reduces Brain Differentiation Between Self and Other Faces
Psychedelic compounds such as psilocybin, LSD and DMT reshape perception and the sense of self by stimulating serotonin (5‑HT2A) receptors densely distributed in the visual cortex and default‑mode network (DMN). Earlier research has shown that psychedelics heighten early visual signals (the P1 event‑related potential, ~90 ms) yet dampen later structural encoding of faces and objects (the N170, ~170 ms). They also diminish the P300 response (300‑500 ms) associated with self‑referential attention and “ego dissolution”. However, no study had directly examined whether psychedelics blur the neural boundary between one’s own face and other faces.
Suay and colleagues therefore tested a rapid‑acting, ayahuasca‑inspired formulation combining intranasal DMT with buccal harmine (a monoamine‑oxidase‑A inhibitor) – referred to as DMT/HAR – to determine its impact on face familiarity processing.
Methods
Experimental design
Find this paper
Ayahuasca-Inspired DMT/HAR Formulation Reduces Brain Differentiation Between Self and Other Faces
https://doi.org/10.1016/j.neuroimage.2025.121247
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Cite this paper (APA)
Suay, D., Aicher, H. D., Kometer, M., Mueller, M. J., Caflisch, L., Hempe, A., ... & Bottari, D. (2025). Ayahuasca-Inspired DMT/HAR Formulation Reduces Brain Differentiation Between Self and Other Faces. NeuroImage, 121247.
Study details
Compounds studied
Ayahuasca
Placebo
Topics studied
Healthy Subjects
Study characteristics
Original Re-analysis
Placebo-Controlled
Double-Blind
Within-Subject
Randomized
Re-analysis
Participants
31
Humans
Institutes
Institutes associated with this publication
University of ZurichWithin the Department of Psychiatry, Psychotherapy and Psychosomatics at the University of Zurich, Dr Mialn Scheidegger is leading team conducting psychedelic research and therapy development.
Compound Details
The psychedelics given at which dose and how many times
DMT 100 mg | 1xLinked Research Papers
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