Naturalistic use of psychedelics does not modulate processing of self-related stimuli (but it might modulate attentional mechanisms): an event-related potentials study comparing non-users and experienced users of classic psychedelics
Paweł Orlowski, Justyna Hobot, Anastasia Ruban, Jan Szczypiński, Michał Bola
December 28, 2023 preprint DOI: 10.31219/osf.io/pw8sm via OpenAlex
Summary
The study found that regular users of psychedelics do not show long-term changes in the neural representation of self when responding to their own name compared to non-users. Both groups had similar P300 ERP amplitudes for the Self-name stimulus. However, psychedelics users displayed a smaller increase in P300 amplitude for task-relevant stimuli compared to non-users, suggesting that psychedelics may influence attention allocation rather than self-representation.
Study at a glance
| Design | cross-sectional study |
|---|---|
| Sample size | 113 |
| Population | experienced psychedelics users and non-users |
| Key finding | Regular naturalistic use of psychedelics may not be related to long-term changes in the representation of self, but could affect attentional resources. |
Abstract
Classic psychedelics are able to profoundly alter the state of consciousness and lead to acute experiences of ego dissolution – the blurring of the distinction between representations of self and the external world. However, whether repeated use of psychedelics is associated with more prolonged and permanent modifications to the concept of self remains to be investigated. Therefore, we conducted a preregistered, cross-sectional study in which experienced psychedelics users (15 or more lifetime experiences with psychedelics; N = 56) were compared to non-users (N = 57) in terms of neural reactivity to a Self-name (i.e., each participant’s own name) stimulus, which is known to robustly activate a representation of self. Two control stimuli were additionally used: an Other-name stimulus, as a passive control condition in which no reaction was required; and a Target-name stimulus, to which participants provided a manual response and which thus constituted an active control condition. Analysis of the amplitude of the P300 ERP component evoked by the Self-name revealed no difference between the psychedelics users and non-users. However, in comparison to non-users, psychedelics users exhibited a smaller increase in P300 amplitude when processing the task-relevant Target-name (in relation to both Self- and Other-names). Therefore, our data suggests that regular naturalistic use of psychedelics may not be related to long-term changes in the representation of self, but it might potentially affect allocation of attentional resources to task-relevant stimuli.