The relation between naturalistic use of psychedelics and perception of emotional stimuli: An ERP study comparing non-users and experienced users of classic psychedelics
Paweł Orlowski, Justyna Hobot, Anastasia Ruban, Jan Szczypiński, Michał Bola
October 9, 2023 preprint DOI: 10.31234/osf.io/uzwa3 via OpenAlex
Summary
Psychedelic users showed weaker neural responses to negative emotional stimuli compared to non-users, specifically exhibiting lower amplitude of the N200 component when processing fearful faces. The study involved 56 experienced psychedelic users and 55 non-users, analyzing their EEG signals while viewing emotional expressions. While there were significant differences in early emotional reactivity, later components related to attention and cognition did not show between-group differences. This suggests that using psychedelics in naturalistic settings may reduce reactivity to negative emotions.
Study at a glance
| Design | observational cohort |
|---|---|
| Sample size | 111 |
| Population | experienced users of psychedelics and non-users |
| Key finding | Naturalistic use of psychedelics is associated with reduced reactivity to emotionally negative stimuli at early processing stages. |
Abstract
Previous research indicates that psychedelic substances taken in well-controlled laboratory or therapeutic settings have the potential to decrease negative and increase positive emotional reactivity. However, it is unclear whether similar effects are associated with using psychedelics in less-controlled naturalistic environments. Therefore, in the present study we compared neural markers of emotional stimuli perception between groups of experienced users of psychedelics (N = 56) and non-users (N = 55). EEG signals were collected while participants were presented with pictures of faces showing neutral or emotional expressions (anger, sadness, happiness). Subsequently, we analyzed event-related potential (ERP) components that are established markers of emotional reactivity. Compared to non-users, psychedelics users exhibited weaker neural responses to negative emotional stimuli, as indicated by significantly lower amplitude of the N200 component when processing fearful faces. Furthermore, the analysis revealed significant interaction effects between Group and Emotion on N170 and N200 amplitudes, thus indicating between-group differences in processing of fearful faces. However, analysis of later ERP components associated with attention and cognitive processes (P200, P300) did not reveal significant between-group differences. Therefore, our results indicate that naturalistic use of psychedelics may be related to reduced reactivity to emotionally negative stimuli at the early and automatic processing stages.