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...
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...
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...
RATIONALE: Reports of resurfaced repressed memories during psychedelic experiences have circulated for decades and still emerge today. However, the veracity of repressed memories remains debated, and the mechanisms through which psychedelics might recover alleged repressed memories are unclear. OBJECTIVES: This scoping review aimed to provide an overview of the literature on repressed memory in...
MDMA's history spans military experimentation, recreational use, and clinical trials for PTSD treatment, reflecting both promise and controversy. While studies in heavy users suggested possible neurotoxicity, evidence remains inconclusive. Clinical trials show that one to three sessions of MDMA-assisted psychotherapy can alleviate PTSD symptoms, yet regulators have criticized inadequate...
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...
Importance: Few pharmacotherapies are approved for treatment-resistant depression, and many patients do not achieve remission following treatment with those therapies. Objective: To examine the efficacy and safety of single-day treatment with a synthetic formulation of inhaled mebufotenin (GH001) vs placebo in patients with treatment-resistant depression. Design, Setting, and Participants: This...
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...
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...
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...
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,...
AbstractBackgroundResearch has shown that psychedelics may have therapeutic potential in treating mental disorders like depression and anxiety. However, the mechanisms and actions underlying their effects are still not fully understood. Similarly, while the significance of mindset and setting in shaping psychedelic experiences and therapeutic outcomes is well established, information about the...
Background: Preliminary research indicates that psychedelics may hold promise as analgesic agents. This study investigated the potential analgesic effects of lysergic acid diethylamide (LSD) microdosing on pain tolerance and subjective pain perception in healthy participants. Methods: Utilizing a randomised, placebo-controlled design, participants received 15 μg of LSD or placebo over four...
Microdosing psychedelics, the regular use of low doses of LSD or psilocybin, have attracted growing public and scientific interest. This review synthesizes findings from 57 human studies on psychological and physiological outcomes in clinical and non-clinical populations. Reported benefits include improved mood, enhanced cognition, social functioning, and mental health, although findings are...
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...
Psychedelic substances exhibit complex interactions with the 'set and setting' of use, that is, the mental state of the user and the environment in which a psychedelic experience takes place. Despite these contextual variables' known importance, psychedelic research has lacked methodological rigor in reporting extra-pharmacological factors. This study aimed to generate consensus-based...
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 =...
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...
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...
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...
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...
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,...
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...
Clinical trials using full doses of psychedelics have provided preliminary evidence supporting their safety and efficacy in treating a variety of physical and psychological conditions. Anecdotal reports indicate that even very small amounts of these substances may provide therapeutic benefits, though robust clinical studies are still needed. This chapter reviews the current experimental studies...
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...