BMJ Open
May 11, 2026
Julia Colcott, Alexandre A. Guerin, Olivia Carter et al.
Despite growing interest in the therapeutic potential of 3,4-methylenedioxymethamphetamine (MDMA), no targeted measure to systematically assess side effects of MDMA-assisted psychotherapy (MDMA-AP) exists. Our aim was to develop an MDMA-Assisted Psychotherapy Side Effects Tool (M-SET) to capture side effects over the course of MDMA-AP. Informed by a systematic review and a review of other...
Biological psychiatry. Cognitive neuroscience and neuroimaging
May 1, 2026
Zachary Anderson, Matthew Gunn, Emily Jones et al.
Cannabis use among young adults has reached the highest levels ever recorded. Evidence indicates that acute Δ9-tetrahydrocannabinol (THC) disrupts brain connectivity. Few studies have examined this on a whole-brain level. We examined the effects of a single moderate dose of THC on resting-state functional brain networks among young adult cannabis users. In a within-subject, double-blind,...
Psychopharmacology
April 15, 2026
Hanna Molla, Evan Hahn, Christian Ramos et al.
Abstract Rationale Many cannabis users claim that one reason they use cannabis is to relieve stress or dampen effects of stressful memories. However, the processes by which cannabis or its primary constituent, Δ 9 -tetrahydrocannabinol (THC) alleviate stressful experiences remains unclear. Objective Here, we assessed whether low oral doses of THC reduce emotional or physiological responses to...
Psychedelic medicine (New Rochelle, N.Y.)
March 1, 2026
Jonah Griffin-Stolbach, Hanna Molla, Donald Hedeker et al.
There has been great interest in the use of very low doses of psychedelic drugs like lysergic acid diethylamide (LSD) to improve mood and cognition. However, controlled studies have thus far provided little support for their efficacy. One challenge is that the subjective effects are subtle and on the threshold of detectability, whereas the questionnaires used to assess the drugs' effects were...
Psychopharmacology
February 1, 2026
Ana Deutsch, Connor J Haggarty, Gavin N Petrie et al.
1 citation
Stimulant drugs such as methamphetamine (MA) and 3,4-methylenedioxymethamphetamine (MDMA) can impact neurobiological systems implicated in stress, reward processing, and drug use. Although recent preclinical evidence implicates the endocannabinoid (eCB) system in these processes, little is known about the acute effects of stimulants on eCB levels in humans. The aim of the present study was to...
Journal of psychopharmacology (Oxford, England)
January 13, 2026
James Glazer, Hanna Molla, Royce Lee et al.
Lysergic acid diethylamide (LSD) has been considered as a potential treatment for depression for over 75 years, but its therapeutic potential has only recently been considered in mainstream psychiatry. Repeated ingestion of low doses of LSD ("microdoses") is thought to reduce depression, but the neurobiology underlying this effect is unknown. We previously reported that low doses of LSD...
Journal of Psychopharmacology
September 16, 2025
Ramona L. Martinez, Nina Radošić, Hanna Molla et al.
1 citation
Our findings extend previous research by demonstrating that MDMA increases feelings of trust in the social world beyond lab-specific interaction partners. These findings are consistent with user reports of generalized social well-being effects and support the idea that MDMA may have clinical value from a social psychological perspective.
Psychedelics
August 26, 2025
Harriet de Wit
Professor Harriet de Wit, a pioneering researcher in psychoactive drugs at the University of Chicago, shares her remarkable 45-year scientific journey in this illuminating Genomic Press Interview. As Director of the Human Behavioral Pharmacology Laboratory and recipient of prestigious honors including the 2019 European Behavioral Pharmacology Society Distinguished Investigator Award, Dr. de Wit...
Biological Psychiatry
May 15, 2025
Anya K. Bershad, Harriet de Wit
3 citations
Social disequilibrium, or disrupted social homeostasis, underlies many behavioral disorders, including problematic drug use. One way to study the relationship between drug use and social homeostasis is to determine whether single doses of psychoactive drugs relieve some of the discomfort of social isolation and promote social connection. In this narrative review, we discuss challenges and...
Frontiers in adolescent medicine
2025
K J Paige, A S Weigard, Olusola Ajilore et al.
Cannabis and its main psychoactive constituent, delta-9-tetrahydrocannabinol (THC), are thought to weaken neurocognitive processes. However, past experimental research examining the acute effects of THC on neurocognition has produced mixed results. The current study aims to advance this literature through application of computational modeling and consideration of individual differences in...
Scientific Reports
December 28, 2024
Harriet de Wit, Evan Hahn, Shahd Smadi et al.
1 citation
Psychoactive drugs such as alcohol and stimulants are typically used in social settings such as bars, parties or small groups. Yet, relatively little is known about how social contexts affect responses to drugs, or how the drugs alter social interactions. It is possible that positive social contexts enhance the rewarding properties of drugs, perhaps increasing their potential for repeated use...
Psychedelic medicine (New Rochelle, N.Y.)
December 1, 2024
Connor J Haggarty, Hanna Molla, James Glazer et al.
2 citations
Despite widespread popular interest in the use of low doses of Lysergic acid diethylamide (LSD) to improve mood, little is known about how these doses affect emotional processing in the brain. In this study, we tested the effect of a single low dose of LSD (26 µg) compared with placebo on electroencephalogram (EEG) event-related potentials (ERP: N170, P300 and Mismatch Negativity) in healthy...
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
June 1, 2024
Conor H. Murray, Joel Frohlich, Connor J Haggarty et al.
30 citations
Neural complexity correlates with one's level of consciousness. During coma, anesthesia, and sleep, complexity is reduced. During altered states, including after lysergic acid diethylamide (LSD), complexity is increased. In the present analysis, we examined whether low doses of LSD (13 and 26 µg) were sufficient to increase neural complexity in the absence of altered states of consciousness. In...
The European journal of neuroscience
June 1, 2024
Connor J Haggarty, Anya K. Bershad, Mahesh K Kumar et al.
1 citation
The 3,4-methylenedioxymethamphetamine (MDMA) has long been used non-medically, and it is currently under investigation for its potential therapeutic benefits. Both uses may be related to its ability to enhance empathy, sociability, emotional processing and its anxiolytic effects. However, the neural mechanisms underlying these effects, and their specificity to MDMA compared to other stimulants,...
Biological psychiatry. Cognitive neuroscience and neuroimaging
May 1, 2024
Robin J Murphy, Suresh Muthukumaraswamy, Harriet de Wit
31 citations
Taking regular low doses of psychedelic drugs (microdosing) is a practice that has drawn recent scientific and media attention for its potential psychotherapeutic effects. Yet, controlled studies evaluating this practice have lagged. Here, we review recent evidence focusing on studies that were conducted with rigorous experimental control. Studies conducted under laboratory settings using...
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
April 1, 2024
Hanna Molla, Royce Lee, Ilaria Tare et al.
37 citations
Recent studies and anecdotal reports suggest that psychedelics can improve mood states, even at low doses. However, few placebo-controlled studies have examined the acute effects of low doses of LSD in individuals with psychiatric symptoms. In the current study, we examined the acute and sub-acute effect of a low dose of LSD (26 µg) on subjective effects and mood in volunteers with mild...
Psychological review
March 1, 2024
Manoj K. Doss, Jason Samaha, Frederick S. Barrett et al.
24 citations
Despite distinct classes of psychoactive drugs producing putatively unique states of consciousness, there is surprising overlap in terms of their effects on episodic memory and cognition more generally. Episodic memory is supported by multiple subprocesses that have been mostly overlooked in psychopharmacology and could differentiate drug classes. Here, we reanalyzed episodic memory confidence...
Journal of psychopharmacology (Oxford, England)
March 1, 2024
Anya K. Bershad, David T Hsu, Harriet de Wit
9 citations
The prosocial compound ± 3,4-methylenedioxymethamphetamine (MDMA) is an amphetamine derivative that has shown promise as an adjunct to psychotherapy in the treatment of post-traumatic stress disorder. MDMA increases positive responses to social images, and it has been suggested that the ability of MDMA to positively bias social perception may underlie its therapeutic efficacy as a psychotherapy...
Imaging neuroscience (Cambridge, Mass.)
2024
Hanna Molla, Giovanni Novembre, Anya K. Bershad et al.
The stimulant ± 3,4-methylenedioxymethamphetamine (MDMA) has been shown to enhance the perceived pleasantness of touch. However, the underlying neural processes contributing to touch-related effects of MDMA are not well understood. Using a double-blind, randomized, within-subject design, this study used fMRI to examine hemodynamic changes following MDMA (1.5 mg/kg) vs. lactose placebo...
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
September 1, 2023
Harriet de Wit, M Heilig, Anya K. Bershad
Psychedelic drugs, when used in the context of psychotherapy, can produce significant and long-lasting memories with enduring beneficial effects. Yet, the behavioral and neurobiological mechanisms that underlie these beneficial effects remain a mystery. Here, we suggest that both the quality and durability of memories of the drug-facilitated therapeutic experience may be mediated, in part, by...
Neuroscience and Biobehavioral Reviews
July 1, 2023
Manoj K. Doss, Harriet de Wit, David A Gallo
30 citations
Psychoactive drugs modulate learning and emotional processes in ways that could impact their recreational and medical use. Recent work has revealed how drugs impact different stages of processing emotional episodic memories, specifically encoding (forming memories), consolidation (stabilizing memories), and retrieval (accessing memories). Drugs administered before encoding may preferentially...
Schizophrenia Bulletin
June 26, 2023
Anya K. Bershad, Harriet de Wit
12 citations
BACKGROUND AND HYPOTHESIS: Diminished social motivation is a negative symptom of schizophrenia and leads to severe functional consequences for many patients suffering from the illness. However, there are no effective medications available to treat this symptom. Despite the lack of approved treatments for patients, there is a growing body of literature on the effects of several classes of drugs...
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
2023
James Glazer, Conor H. Murray, Robin Nusslock et al.
52 citations
Renewed interest in classic psychedelics as treatments for psychiatric disorders warrants a deeper understanding of their neural mechanisms. Single, high doses of psychedelic drugs have shown promise in treating depressive disorders, perhaps by reversing deficits in reward processing in the brain. In addition, there are anecdotal reports that repeated ingestion of low doses of LSD, or...
Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology
June 1, 2022
Conor H. Murray, Zhengyi Huang, Royce Lee et al.
Increased cannabis availability has contributed to increased use with concomitant incidence of adverse effects. One risk factor for adverse drug reactions may be age. There is preclinical evidence that acute effects of delta-9-tetrahydrocannabinol (THC), the primary active constituent of cannabis, are greater during adolescence, but this has not been fully studied in humans. The present study...
Journal of psychopharmacology (Oxford, England)
March 1, 2022
Harriet de Wit, Anya K. Bershad, Charles S. Grob
11 citations
Despite substantial progress in the use of mind-altering drugs to treat psychiatric disorders, the psychological processes through which these drugs change mood or behavior are poorly understood. Controlled laboratory studies with well-defined psychological constructs are valuable to understand how these drugs manifest their therapeutic benefit. However, there are substantial methodological...