September 24, 2026
Alexander V. Lebedev
preprint
Dream reports exhibit reproducible organization at multiple scales. We analyzed >75,000 reports from four platforms: 30,241 reports by 5,524 Dreamseer users and ~45,000 from DreamBank, Reddit r/Dreams, and the Sleep and Dream Database. Within reports, emotional valence declined from beginning to end. Forward and reversed trajectories were distinguishable in all five corpus-language samples with...
Scientific Reports
February 10, 2026
Michelle Olofsson, Kasim Acar, Otto Simonsson et al.
Recent research has highlighted the potential of 3,4-methylenedioxymethamphetamine (MDMA)-assisted psychotherapy for the treatment of post-traumatic stress disorder and other trauma-related psychiatric conditions. However, less is known about the effects of MDMA use on psychological well-being in populations with trauma histories outside of clinical contexts. In the present study, we assessed...
Journal of Affective Disorders
January 26, 2024
Ludwig Honk, Cecilia U.D. Stenfors, Simon B. Goldberg et al.
41 citations
It has long been speculated that psychedelic use could provoke the onset of psychosis, but there is little evidence to support this conjecture. Using a longitudinal research design with samples representative of the US and UK adult populations with regard to sex, age, and ethnicity (n = 9732), we investigated associations between psychedelic use and change in the number of psychotic symptoms...
Scientific Reports
September 30, 2023
Alexander V. Lebedev, Kasim Acar, Otilia Horntvedt et al.
9 citations
Previous research has suggested that classical psychedelics can foster significant and enduring changes in personality traits and subjective wellbeing. Despite the lack of evidence for adverse effects on mental health stemming from psychedelic use, concerns persist regarding the capacity of these substances to modulate information processing and attitudes towards factual data. The aim of the...
Scientific Reports
July 23, 2021
Alexander V. Lebedev, Kasim Acar, Benjamín Garzón et al.
19 citations
Abstract Despite recently resurrected scientific interest in classical psychedelics, few studies have focused on potential harms associated with abuse of these substances. In particular, the link between psychedelic use and psychotic symptoms has been debated while no conclusive evidence has been presented. Here, we studied an adult population (n = 1032) with a special focus on young (18–35...
Human Brain Mapping
May 6, 2016
Alexander V. Lebedev, Mendel Kaelen, Martin Lövdén et al.
333 citations
Personality is known to be relatively stable throughout adulthood. Nevertheless, it has been shown that major life events with high personal significance, including experiences engendered by psychedelic drugs, can have an enduring impact on some core facets of personality. In the present, balanced-order, placebo-controlled study, we investigated biological predictors of post-lysergic acid...
Human Brain Mapping
May 22, 2015
Alexander V. Lebedev, Martin Lövdén, Gidon Rosenthal et al.
347 citations
Ego-disturbances have been a topic in schizophrenia research since the earliest clinical descriptions of the disorder. Manifesting as a feeling that one's "self," "ego," or "I" is disintegrating or that the border between one's self and the external world is dissolving, "ego-disintegration" or "dissolution" is also an important feature of the psychedelic experience, such as is produced by...