Journal of Psychopharmacology
August 1, 2022
Paweł Orłowski, Anastasia Ruban, Jan Szczypiński et al.
40 citations
People who have used psychedelics more times over their lifetime tend to show greater positive emotional reactions and lower negative emotional reactions, along with more reflection and internal self-awareness, and less rumination and concern about how others see them. These associations were explained largely by the intensity of past ego-dissolution and mystical experiences during psychedelic use. The findings suggest that regular naturalistic use of psychedelics is linked to adaptive, lasting changes in emotional reactivity and self-consciousness, which may underlie previously observed increases in well-being among users.
Frontiers in psychology
January 1, 2018
Michał Bola, Paweł Orłowski, Karolina Baranowska et al.
11 citations
Brain signal diversity is a marker of consciousness, being lower in unconscious states and higher during psychedelic states. This study tested whether increasing the information rate of speech would increase signal diversity, reflecting richer experience. Nineteen participants listened to an audiobook at five speeds (65–135% of original) and to backward (unintelligible) speech, plus a resting-state condition. EEG Lempel-Ziv diversity was measured. The main hypothesis was not supported: Bayes Factor showed evidence for no effect of speech speed on diversity. Resting-state diversity was greater than during any speech condition. Diversity also gradually declined over the experiment, possibly due to decreasing vigilance, suggesting that unconstrained rest allows more varied experiences like mind wandering.
Scientific Reports
March 1, 2023
Paweł Orłowski, Michał Bola
9 citations
Greater meaningfulness of visual stimuli is linked to higher Lempel–Ziv diversity of EEG signals, but the opposite effect occurs for auditory stimuli. Visual perception generally produces higher EEG diversity than auditory perception. Compared to resting state, meaningful visual stimuli increase EEG diversity while meaningful auditory stimuli decrease it. These findings show that brain signal diversity depends on the sensory modality being stimulated, so it cannot serve as a generic measure of the variability of conscious experience.
Psychophysiology
August 1, 2024
Paweł Orłowski, Justyna Hobot, Anastasia Ruban et al.
5 citations
Regular naturalistic use of classic psychedelics does not appear to alter long-term neural representations of the self, but it may affect how attentional resources are allocated to task-relevant stimuli. In a cross-sectional study comparing 56 experienced psychedelics users (15 or more lifetime uses) with 57 nonusers, no difference was found in the P300 brain response to hearing one's own name, a stimulus that robustly activates self-representation. However, psychedelics users showed a larger P300 response to other people's names and a smaller increase in P300 amplitude when processing task-relevant target names compared to nonusers. These results suggest that while self-representation remains unchanged, regular psychedelic use might subtly shift attentional processing.
Journal of psychoactive drugs
February 13, 2025
Stanisław Adamczyk, Małgorzata Paczyńska, Anastasia Ruban et al.
2 citations
Psychedelics can cause profound changes in cognition, emotion, and perception, but the intensity of these effects varies widely. A cross-sectional online survey of 862 psychedelics users (701 had used LSD and 553 had used psilocybin mushrooms) examined how internal and external contextual factors relate to the intensity of ego dissolution. Those who used psychedelics for spiritual or self-healing purposes reported more intense ego dissolution, while those motivated by curiosity reported less intense experiences. The social context and physical environment were not strongly linked to the reported intensity. This suggests that internal mindset, rather than external setting, may be more influential in naturalistic use.
Progress in neuro-psychopharmacology & biological psychiatry
January 10, 2025
Anastasia Ruban, Mikołaj Magnuski, Justyna Hobot et al.
1 citation
People who use psychedelics in natural settings show weaker increases in alpha and beta brainwave power when thinking about themselves, compared to non-users, especially in regions like the posterior cingulate cortex that handle self-related information and memory. However, these differences were not replicated in a second, smaller dataset, limiting confidence in the finding. The results contribute to ongoing debate about how long psychedelic effects last in brain circuits linked to self-processing and question the specific role of default-mode network hubs in such changes.
bioRxiv (Cold Spring Harbor Laboratory)
April 2, 2026
Maja Wójcik, Paweł Orłowski, Stanisław Adamczyk et al.
Long-term naturalistic psychedelic users who had abstained for at least 30 days showed largely no significant differences in brain oscillatory power, signal complexity, or network connectivity compared to non-users, contrary to patterns seen in acute administration studies. Complexity was unexpectedly lower in users during eyes-open conditions. Effective connectivity within and between key brain networks (Default Mode, Salience, Central Executive) showed no group differences after correction. These null findings suggest that repeated psychedelic use may not produce lasting neurophysiological changes detectable in resting-state EEG during abstinence, possibly due to homeostatic adaptation or individual variability.
Human Brain Mapping
April 1, 2026
Paweł Orłowski, Aleksandra Domagalik, Michał Bola
People who have used classic psychedelics many times (at least 10 lifetime uses) recognize angry facial expressions more quickly and accurately than nonusers, indicating enhanced processing of threat-related cues. In an fMRI study comparing 33 experienced psychedelic users with 34 matched nonusers, users showed reduced brain activation to angry faces in key limbic and salience network regions, along with heightened responses to happy expressions in parietal and sensorimotor cortices and increased precuneus activation to fearful expressions. Reduced differentiation between emotional categories appeared in two default mode network nodes. These neurofunctional changes suggest that naturalistic psychedelic use modulates emotional processing in ways that complement findings from clinical settings.