bioRxiv (Cold Spring Harbor Laboratory)
August 10, 2026
Aedan O'Shea, Natasha L. Mason, Jacco Briede et al.
preprint
Abstract Psilocybin acutely alters neurotrophic, neurochemical, and immune markers, but the relationships between these responses and circulating microRNAs (miRNAs), i.e. non-coding RNAs that regulate post-transcriptional gene expression, remain unclear. In a randomized, double-blind, placebo-controlled study of 62 healthy adults who received psilocybin (0.17 mg/kg) or placebo, we previously...
Molecular Psychiatry
August 4, 2026
Kim P. C. Kuypers, Natasha L. Mason, Aurelie Carlier et al.
Women experience a disproportionate burden of affective and stress-related disorders, with symptom variability shaped by endocrine transitions across the menstrual cycle, pregnancy, postpartum, and menopause. Although psychedelic-assisted therapies are increasingly investigated for these conditions, hormonal state represents a largely unaccounted determinant of variability in exposure,...
bioRxiv (Cold Spring Harbor Laboratory)
July 13, 2026
Natasha L. Mason, Eline Chm Haijen-Bongers, Kim P. C. Kuypers et al.
Serotonergic psychedelics are advancing as psychiatric treatments, yet acute responses vary between individuals and the contribution of sex, a fundamental biological variable, remains largely unexamined. We pooled two double-blind, placebo-controlled studies in healthy volunteers (N = 72; 31 male, 41 female) comparing psilocybin 15 mg, 2C-B 20 mg, and LSD 50 μg. Linear mixed models tested sex...
Journal of Psychedelic Studies
July 3, 2026
Henry J. Whitfield, Jan Schepers, Natasha L. Mason et al.
Abstract Despite growing interest in psychedelic-assisted psychotherapy, research investigating the psychotherapeutic components is lacking. This leaves unanswered questions regarding the psychotherapy's necessity and form. This observational study addresses this gap by measuring the outcomes of a psilocybin truffle retreat, followed by the outcomes of two psychotherapy interventions that...
Journal of Psychedelic Studies
June 26, 2026
Malin V. Uthaug, Jack G. Allocca, Martha N. Havenith et al.
Abstract Background The Pivotal Mental States (PiMS) construct posits that psychedelics and other stress-inducing practices, such as fasting and hypoxia, can evoke transformative mental states through increased serotonin receptor activation in the brain. These states are associated with enhanced cognitive flexibility, accelerated associative learning, and psychological insights that may...
Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie
June 1, 2026
Francisco Madrid-Gambin, Pablo Mallaroni, Noemí Haro et al.
Ayahuasca is a psychoactive brew containing N,N-dimethyltryptamine (DMT) and β-carboline alkaloids that induces marked alterations in perception, emotion and self-referential processing. However, the multiscale biological organization linking peripheral metabolism, brain network dynamics, neurochemistry, and subjective experience in humans remains poorly understood. Here, we applied an...
Nature Medicine
April 1, 2026
Manesh Girn, Manoj K. Doss, Leor Roseman et al.
8 citations
Psychedelic drugs are re-emerging as promising scientific and clinical tools. However, despite a rapidly expanding literature on their therapeutic value, the neural mechanisms underlying psychedelic effects remain unclear. Resting-state functional magnetic resonance imaging studies of acute psychedelic effects, conducted independently by several research groups, have so far yielded fragmented...
Molecular Psychiatry
February 3, 2026
Pablo Mallaroni, S. Parker Singleton, Natasha L. Mason et al.
As psychedelic-assisted psychotherapy gains momentum, clinical investigation of next-generation psychedelics may lead to novel compounds tailored for specific populations. 2,5-dimethoxy-4-bromophenethylamine (2C-B) is a psychedelic phenethylamine reported to produce less dysphoria and subjective impairment than the psychedelic tryptamine psilocybin. Despite its popularity among recreational...
Advanced Science
November 20, 2025
Paolo Cardone, Charlotte Martial, Yonatan Sanz Perl et al.
3 citations
Abstract Disorders of consciousness (DoC), including unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS), have limited treatment options and are characterized by low complexity of brain activity. Recent research suggests that psychedelic drugs, which enhance the complexity of brain activity, could offer promising therapies. Here, individualized whole‐brain computational...
November 17, 2025
Krishna Prasad Bhavaraju, Natasha L. Mason, Pablo Mallaroni et al.
preprint
Abstract Psilocybin induces profound alterations in consciousness, yet prevailing neural models often describe a monolithic change in brain connectivity that may not fully capture the multifaceted nature of the psychedelic state. To test the hypothesis of a composite neural state, this study applied a robust, data-driven framework, Connectome Independent Component Analysis (connICA) with...
Biological Psychiatry
October 21, 2025
Katharina S Lege, Pablo Mallaroni, Sepehr Mortaheb et al.
1 citation
Background The impact of acute cannabis exposure on brain function and cognitive performance varies among individuals. Acute effects of cannabis on behavior may be absent or benign in chronic users, while occasional users experience significant impairment in day-to-day operations. It is hypothesized that repeated cannabis use induces neuroadaptations leading to tolerance and desensitization,...
Br J Pain
September 4, 2025
Mauro Cavarra, Nadia R. P. W. Hutten, Jan Schepers et al.
A randomised placebo-controlled study of the effects of lysergic acid diethylamide microdosing (15 μg) on pain perception in healthy volunteers.
Journal of Psychedelic Studies
September 4, 2025
Giordano Novak Rossi, Rishma S. I. Khubsing, Eline Haijen et al.
Abstract Background and aims Research on classical psychedelics like ayahuasca is increasingly focused on treating mental disorders and enhancing well-being. Ayahuasca has shown promise in improving cognitive flexibility, emotion regulation, and sleep, though findings are mixed and further research is needed. This study tracked participants over three months, assessing cognitive flexibility,...
July 3, 2025
Natasha L. Mason, Pablo-Alexandre Mallaroni, Attila Szabo et al.
preprint
Promising results have emerged in the use of psychedelic drugs for treating depression. Despite multiple neural models attempting to elucidate the acute psychedelic experience, and an increased focus on potential mechanisms driving persistent change, the connections between the acute state and the enduring therapeutic outcomes remain elusive. This targeted review aims to bridge this gap by...
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
June 1, 2025
Johannes G. Ramaekers, Johannes T. Reckweg, Natasha L. Mason et al.
8 citations
3-Methylmethcathinone (3-MMC) is a designer drug that belongs to the group of synthetic cathinones. The compound has been scheduled in many jurisdictions because of public health concerns associated with excessive use. To date, there are no clinical studies that have evaluated the risk profile of 3-MMC in the recreational range of low to moderate doses. The current, first-in-human study (N =...
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
May 1, 2025
Francisco Madrid-Gambin, Noemí Haro, Natasha L. Mason et al.
4 citations
Acute intoxication from Δ9-tetrahydrocannabinol (THC, the primary active ingredient of cannabis) can lead to neurocognitive impairment and interference with day-to-day operations, such as driving. Present evaluations of THC-induced impairment in legal settings rely on biological drug tests that solely establish cannabis use, rather than cannabis impairment. The current study evaluated the...
Psychopharmacology
April 30, 2025
Johannes G. Ramaekers, Johannes T. Reckweg, Natasha L. Mason et al.
4 citations
3-Methylmethcathinone (3-MMC) is a synthetic cathinone that has been scheduled in many jurisdictions after it appeared on the consumer market as a designer drug or "legal high". At present, there are no medical applications for synthetic cathinones, but in the past cathinone and other compounds that are structurally related to amphetamine have been evaluated and recognized for their intrinsic...
Journal of psychopharmacology (Oxford, England)
April 1, 2025
Manoj K. Doss, Lilian Kloft, Natasha L. Mason et al.
5 citations
Ayahuasca is an Amazonian brew with 5-HT2A-dependent psychedelic effects taken by religious groups globally. Recently, psychedelics have been shown to impair the formation of recollections (hippocampal-dependent episodic memory for specific details) and potentially distort memory while remembering. However, psychedelics spare or enhance the formation of familiarity-based memory...
American Journal of Psychiatry
2025
Johannes G. Ramaekers, Johannes T. Reckweg, Natasha L. Mason
25 citations
Unlike classical antidepressants, psychedelics such as psilocybin have been shown to induce a rapid antidepressant response. In the wake of this development, interest has emerged in ultra-fast, short-acting psychedelics such as 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) and N,N-dimethyltryptamine (DMT) with the expectation that these can produce rapid antidepressant effects following an...
Neuroscience of Consciousness
2025
Christopher Timmermann, James W. Sanders, David Reydellet et al.
19 citations
5-MeO-DMT is a short-acting psychedelic that is anecdotally reported to induce a radical disruption of the self and a paradoxical quality of aroused, waking awareness that is nevertheless devoid of any specific perceptual contents. Here, we conducted an exploratory observational study of the phenomenological and neuronal effects of this compound. We collected micro-phenomenological interviews,...
Frontiers in Psychology
2025
Johannes T. Reckweg, Natasha L. Mason, Eef L. Theunissen et al.
2 citations
A three-item Peak Experience Scale (PES) was developed to rapidly evaluate the strength of the psychoactive experience, and to guide the dosing regimen, of the psychedelic 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT; mebufotenin). This paper aims to compare the PES with a range of established questionnaires designed to evaluate the psychedelic experience. Data were gathered from three separate...
bioRxiv (Cold Spring Harbor Laboratory)
October 22, 2024
Pablo Mallaroni, S. Parker Singleton, Natasha L. Mason et al.
2 citations
preprint
As psychedelic-assisted psychotherapy gains momentum, clinical investigation of next-generation psychedelics may lead to novel compounds tailored for specific populations. 2,5-dimethoxy-4-bromophenethylamine (2C-B) is a psychedelic phenethylamine reported to produce less dysphoria and subjective impairment than the psychedelic tryptamine psilocybin. Despite its popularity among recreational...
Biological psychiatry. Cognitive neuroscience and neuroimaging
October 1, 2024
Manoj K. Doss, Pablo Mallaroni, Natasha L. Mason et al.
7 citations
As research on psychedelics (hallucinogenic serotonin receptor 2A agonists) progresses, it is important to delineate the reliability of supposedly unique effects across this drug class. One such effect is how psychedelics impair the formation (i.e., encoding) of hippocampal-dependent recollections (retrieval of specific details) while potentially enhancing the encoding of cortical-dependent...
Translational Psychiatry
July 15, 2024
Nadia R. P. W. Hutten, Conny W E M Quaedflieg, Natasha L. Mason et al.
16 citations
The repeated use of small doses of psychedelics (also referred to as "microdosing") to facilitate benefits in mental health, cognition, and mood is a trending practice. Placebo-controlled studies however have largely failed to demonstrate strong benefits, possibly because of large inter-individual response variability. The current study tested the hypothesis that effects of low doses of LSD on...
Biological psychiatry. Cognitive neuroscience and neuroimaging
July 1, 2024
Sepehr Mortaheb, Larry D. Fort, Natasha L. Mason et al.
15 citations
Psilocybin is a widely studied psychedelic substance that leads to the psychedelic state, a specific altered state of consciousness. To date, the relationship between the psychedelic state's neurobiological and experiential patterns remains undercharacterized because they are often analyzed separately. We investigated the relationship between neurobiological and experiential patterns after...