Behaviour Research and Therapy
August 10, 2026
Otto Simonsson, Christian A. Webb, Mini Ruiz et al.
Despite decades of meditation research, there is a lack of preregistered and well-powered studies that investigate the effects of brief meditation practices on subjective wellbeing and use data-driven approaches to predict response to these interventions. Using representative samples of the US and UK adult populations with regards to age, sex, and ethnicity (N = 5049), we conducted a...
Psychedelic Medicine
June 22, 2026
Otto Simonsson, Peter S. Hendricks, Walter Osika et al.
Background: Previous research indicates that psychedelics may produce outcomes that are dependent on the immediate context. Recent scholarship hypothesizes that such outcomes may also depend on the broader sociocultural context, but empirical data are lacking. Methods: Using a longitudinal observational research design with a large sample of US adults ( N = 21,990) followed during a 2-month...
JMIR Mental Health
June 12, 2026
Polina Beloborodova, Lillian M. Smith, Kevin M. Riordan et al.
Background: Digital meditation-based interventions (MBIs) reach vast global audiences with millions of active users, yet concerns persist about the frequency and nature of adverse experiences (ie, AExs) occurring during meditation training. Some researchers have argued that AExs are substantially underdetected and reflect iatrogenic harm caused by meditation (ie, adverse effects [AEfs]). Others...
Research Square
May 19, 2026
Sunjuri Sun, Claudia Hanson, Peter S. Hendricks et al.
As the cultural, scientific, and legal landscape surrounding psychedelics continues to shift toward greater access and acceptability, it is likely that increasing numbers of women of reproductive age may be exposed to these substances. Despite this, the evidence on antenatal exposure has not been systematically reviewed. To synthesize the human literature on child and maternal outcomes...
JAMA Network Open
May 7, 2026
Peter S. Hendricks, Sara N Lappan, Richard C. Shelton et al.
4 citations
Importance: Cocaine use disorder is a serious public health problem and no medications have been proven effective for its treatment. Objective: To evaluate psilocybin in the treatment of cocaine use disorder. It was hypothesized that psilocybin, compared with placebo, would yield a higher percentage of cocaine abstinent days, a greater likelihood of complete abstinence from cocaine, and a...
Journal of psychopharmacology (Oxford, England)
May 1, 2026
Otto Simonsson, Sunjuri Sun, Laura W. Wesseldijk et al.
While psychedelics have shown initial promise in the treatment of migraine, experimental studies have relied on small and homogenous samples, which limit the reliability and generalizability of findings. These limitations underscore the complementary value of other research designs that leverage larger and more representative samples. This cross-sectional study included three cohorts of twins...
Journal of psychopharmacology (Oxford, England)
May 1, 2026
Otto Simonsson, Taylor Lyons, Joseph Marks et al.
Previous research suggests that psychedelics may, under certain conditions, decrease authoritarian attitudes, but larger and more rigorously designed studies are needed to confirm these findings. We aimed to examine the effects of psychedelic use on authoritarian attitudes. Using data from three separate studies with different designs and populations, we investigated the relationship between...
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...
Scientific Reports
January 28, 2026
Nicholas A. Carlisle, Otto Simonsson, Sarah Maccarthy et al.
Psychedelic use has been linked to major life changes that may impact health outcomes, yet few studies have systematically examined the prevalence, types, and demographic characteristics that may be associated with such changes. This paper draws subsamples of respondents who endorsed lifetime psychedelic use from two samples of US adults - one nationally representative by age, race/ethnicity,...
Int J Drug Policy
December 13, 2025
Michelle Olofsson, Walter Osika, Simon B. Goldberg et al.
2 citations
BACKGROUND: Naturalistic psychedelic use can result in a range of difficulties that impair social, occupational, and other important areas of functioning. Yet, the prevalence, phenomenology, and etiology of these outcomes remain poorly understood. Recent qualitative research has shown that individuals with long-term difficulties after psychedelic use sometimes attribute their challenges to...
Journal of Affective Disorders
July 9, 2025
Otto Simonsson, Peter S. Hendricks, Caroline M. Swords et al.
8 citations
While growing evidence suggests that psychedelic-assisted therapy may have antidepressant effects in certain populations, little is known about the effects of psychedelic use on depressive symptoms in non-clinical, naturalistic settings. This observational cohort study included a large sample of US residents (18-50 years old) and longitudinally evaluated the relationships between naturalistic...
Psychopharmacology
July 1, 2025
Otto Simonsson, Simon B. Goldberg, Richard Chambers et al.
33 citations
Research on psychedelics has recently shown promising results in the treatment of various psychiatric disorders, but relatively little remains known about the psychiatric risks associated with naturalistic use of psychedelics. The objective of the current study was to investigate associations between naturalistic psychedelic use and psychiatric risks. Using a sample representative of the US...
Psychedelic medicine (New Rochelle, N.Y.)
June 1, 2025
Haley Maria Dourron, Melissa Bradley, Otto Simonsson et al.
7 citations
Prior research examining the associations between psychedelic use and general psychotic symptoms has yielded mixed findings. However, no studies have investigated the relationships between psychedelic use and specific psychotic symptoms, and whether these relationships might differ among those with liability to psychosis, namely those with a history of psychotic or bipolar disorders. Using...
Int J Neuropsychopharmacol
April 1, 2025
Jacob S. Aday, Otto Simonsson, Emmanuelle A. D. Schindler et al.
25 citations
Classic psychedelics have shown promise in the treatment of various neuropsychiatric disorders. However, weak blinding integrity has been argued to limit the interpretability of therapeutic effects observed in psychedelic clinical trials, highlighting the need to explore alternative active placebos. Here, we aimed to describe the drawbacks of current placebo conditions used in classic...
Psychol Med
March 31, 2025
Otto Simonsson, Simon B. Goldberg, Walter Osika et al.
16 citations
BACKGROUND: Findings from contemporary clinical trials suggest that psychedelics are generally safe and may be effective in the treatment of various psychiatric disorders. However, less is known about the risks associated with psychedelic use outside of medically supervised contexts, particularly in populations that are typically excluded from participation in clinical trials. METHODS:...
J Psychiatr Res
March 17, 2025
Otto Simonsson, Sankalp Chaturvedi, Peter S. Hendricks et al.
2 citations
Previous research has investigated associations between psychedelic experiences and meditation practice, but knowledge gaps remain. Using a longitudinal research design with a sample of US residents between 18 and 50 years old (N = 13,012), we investigated associations between psychedelic-related and meditation-related variables. The follow-up survey was completed by 7484 respondents, of whom...
Journal of psychopharmacology (Oxford, England)
March 12, 2025
Zusanna Bjurenfalk, Alva Cosmo, Otto Simonsson et al.
3 citations
Migraine and cluster headache are two primary headache disorders for which conventional treatments are limited. Classic psychedelic substances such as lysergic acid diethylamide (LSD) and psilocybin are potentially promising new treatment candidates for these conditions. The aim of the present study was to investigate the possible relationship between the lifetime use of classic psychedelics...
bioRxiv (Cold Spring Harbor Laboratory)
March 11, 2025
Devon Stoliker, Leonardo Novelli, Moein Khajehnejad et al.
8 citations
preprint
Abstract Psychedelics can profoundly alter consciousness by reorganising brain connectivity; however, their effects are contextsensitive. To understand how this reorganisation depends on the context, we collected and comprehensively analysed the largest psychedelic neuroimaging dataset to date. Sixty-two adults were scanned with functional MRI and EEG during rest and naturalistic stimuli...
PLoS One
February 12, 2025
Zishan Jiwani, Simon B. Goldberg, Jack Stroud et al.
3 citations
INTRODUCTION: Meditation practice and psychedelic use have attracted increasing attention in the public sphere and scientific research. Both methods induce non-ordinary states of consciousness that may have significant therapeutic benefits. Thus, there is growing scientific interest in potential synergies between psychedelic use and meditation practice with some research suggesting that...
Psychiatr Res Clin Pract
February 11, 2025
Jules Evans, Marc Aixalà, Brian T Anderson et al.
18 citations
Objective: This article outlines recommendations from 30 psychedelic researchers on how to create a better psychedelic safety net. Methods: A survey of 30 psychedelic researchers asked them to identify key critical research gaps around psychedelic harm and safety. Results: The critical research gaps identified by the authors included defining the main types of psychedelic harm, the predictors...
The Journal of rural health : official journal of the American Rural Health Association and the National Rural Health Care Association
2025
Melissa Bradley, Daniel H. Grossman, Otto Simonsson et al.
1 citation
Recent legislative initiatives in the United States have focused on the medical and legal status of psychedelics, prompting interest in understanding public perceptions of their risks. This study investigates rural-urban differences in the perception of LSD and cannabis risks using national survey data. Data from the National Survey of Drug Use and Health (NSDUH) between 2015 and 2021 were...
JAMA Health Forum
November 1, 2024
Otto Simonsson, Matthew W. Johnson, Peter S. Hendricks
10 citations
This Viewpoint discusses the need to better understand potential risks associated with psychedelic and 3,4-methylenedioxymethamphetamine (MDMA) use to ensure safe and ethical practice and identifies 4 key research goals.
J Psychopharmacol
October 29, 2024
Otto Simonsson, Simon B. Goldberg, Peter S. Hendricks
4 citations
Into the wild frontier: Mapping the terrain of adverse events in psychedelic-assisted therapies.
PLoS One
May 13, 2024
Otto Simonsson, Stephen D. Fisher
2 citations
OBJECTIVES: The objectives of this study were to examine the prevalence and associations of mindfulness meditation use and also its perceived mental health effects during the COVID-19 pandemic. METHODS: Using repeated cross-sectional data from broad online samples weighted to be representative of the adult population in Britain, we estimated the prevalence of mindfulness meditation use and...
Psychological Medicine
April 1, 2024
Otto Simonsson, Walter Osika, Cecilia U.D. Stenfors et al.
15 citations
Previous research has proposed that there may be potential synergies between psychedelic and meditation interventions, but there are still knowledge gaps that merit further investigation. Using a longitudinal observational research design with samples representative of the US and UK adult population with regard to sex, age, and ethnicity (N = 9732), we investigated potential associations...