JAMA Psychiatry
June 1, 2026
Ben Deverett, Duan Li, Theresa R. Lii et al.
1 citation
Ketamine has well-known dissociative, analgesic, and antidepressant properties, but it is unknown whether the neurophysiologic effects that are associated with these properties can be modulated separately from one another. Considering that specific cortical oscillations have been associated with specific therapeutic effects, modulating selective aspects of ketamine neurophysiology could inform...
Progress in Neuro-psychopharmacology and Biological Psychiatry
February 18, 2026
Dimitri Henriques Daldegan-Bueno, C Donegan, Rachael Sumner et al.
1 citation
Results suggest short-term improvements in mood following microdosed LSD in people with depression, warranting confirmation in controlled trials. It provides the pharmacokinetic parameters of 8 μg of LSD in a sample of people with depression and indicates no tolerance or sensitisation to repeated microdoses of LSD, despite incremental dose titration.
Ther Adv Psychopharmacol
December 4, 2025
Carina Joy Donegan, Dimitri Daldegan-Bueno, Rachael Sumner et al.
What is it like to microdose LSD for depression? a thematic analysis of participant interviews from an open-label trial.
Neuropharmacology
December 1, 2025
Carina Joy Donegan, Dimitri Daldegan-Bueno, Tehseen Noorani et al.
4 citations
Expectations can impact antidepressant treatment and psychedelic therapy, often enhancing placebo effects and influencing outcomes. However, research in this context is lacking. Our study explored the expectations of participants with major depressive disorder (MDD) before microdosing lysergic acid diethylamide (LSD) in an open-label trial. Twenty-three individuals with MDD completed a...
Neuropharmacology
November 5, 2025
Dimitri Daldegan-Bueno, C Donegan, Rachael Sumner et al.
4 citations
Major depressive disorder (MDD) affects approximately 5 % of the global population. Classic psychedelics have shown promise in treating various mental health disorders. This study evaluated the feasibility and tolerability of an 8-week regimen of microdosed lysergic acid diethylamide (LSD) as a treatment for major depressive disorder in an open-label phase 2A trial (LSDDEP1). Nineteen...
Therapeutic Advances in Psychopharmacology
September 1, 2025
Suresh Muthukumaraswamy, Matthew J. Baggott, Eduardo Ekman Schenberg et al.
8 citations
Psychedelic-assisted therapy (PAT) has typically been evaluated using conventional randomised controlled trials (RCTs), which assess treatment efficacy under highly controlled conditions. However, PAT constitutes a complex intervention, integrating pharmacological, psychotherapeutic and contextual elements that interact dynamically with patient experiences and healthcare settings. Conventional...
medRxiv
August 7, 2025
Ben Deverett, Duan Li, Theresa R. Lii et al.
preprint
Structured Abstract Importance Ketamine has well known dissociative, analgesic, and antidepressant properties, but it is unknown whether the neurophysiologic effects that are associated with these properties can be modulated separately from one another. Given prior studies that link specific cortical oscillations with specific therapeutic effects, it is likely that modulating selective aspects...
Journal of Psychedelic Studies
May 16, 2025
Anna-Leigh Hodge, Anna Forsyth, Tehseen Noorani et al.
6 citations
Abstract Psilocybin, a naturally occurring psychedelic compound found in certain fungi has long been used by Indigenous cultures within ritual and ceremony for healing and spiritual purposes (Spiers et al., 2024). While emerging evidence points to psychedelic agents being novel avenues for the treatment of substance use disorders, the predominantly Western medical models of psychedelic-assisted...
medRxiv : the preprint server for health sciences
October 21, 2024
Pascal Grumbach, Jan Kasper, Joerg F. Hipp et al.
1 citation
preprint
Autism spectrum disorder (ASD) is a neurodevelopmental condition associated with altered resting-state brain function. An increased excitation-inhibition (E/I) ratio is discussed as a potential pathomechanism but in-vivo evidence of disturbed neurotransmission underlying these functional alterations remains scarce. We compared rs-fMRI local activity (LCOR) between ASD (N=405, N=395) and...
Trials
August 24, 2024
Dimitri Daldegan-Bueno, Carina Joy Donegan, Anna Forsyth et al.
14 citations
Major depressive disorder (MDD) poses a significant global health burden with available treatments limited by inconsistent efficacy and notable side effects. Classic psychedelics, including lysergic acid diethylamide (LSD), have garnered attention for their potential in treating psychiatric disorders. Microdosing, the repeated consumption of sub-hallucinogenic doses of psychedelics, has emerged...
Translational Psychiatry
April 15, 2024
Nathan Allen, Aron Jeremiah, Robin J Murphy et al.
15 citations
Microdosing psychedelic drugs at a level below the threshold to induce hallucinations is an increasingly common lifestyle practice. However, the effects of microdosing on sleep have not been previously reported. Here, we report results from a Phase 1 randomized controlled trial in which 80 healthy adult male volunteers received a 6-week course of either LSD (10 µg) or placebo with doses...
Translational Psychiatry
February 24, 2024
Rachael Sumner, Rebecca McMillan, Anna Forsyth et al.
7 citations
Revealing the acute cortical pharmacodynamics of an antidepressant dose of ketamine in humans with depression is key to determining the specific mechanism(s) of action for alleviating symptoms. While the downstream effects are characterised by increases in plasticity and reductions in depressive symptoms-it is the acute response in the brain that triggers this cascade of events. Computational...
Pilot and Feasibility Studies
October 5, 2023
Carina Joy Donegan, Dimitri Daldegan-Bueno, Rachael Sumner et al.
23 citations
Globally, an estimated 260 million people suffer from depression [1], and there is a clear need for the development of new, alternative antidepressant therapies. In light of problems with the tolerability and efficacy of available treatments [2], a global trend is emerging for patients to self-treat depression with microdoses of psychedelic drugs such as lysergic acid diethylamide (LSD) and...
Biological Psychiatry
September 15, 2023
Robin J Murphy, Rachael Sumner, William Evans et al.
69 citations
Microdosing psychedelic drugs is a widespread social phenomenon with diverse benefits claimed for mood and cognition. Randomized controlled trials have failed to support these claims, but the laboratory-based dosing in trials conducted to date may have limited ecological validity. Healthy male volunteers were randomized into lysergic acid diethylamide (LSD) (n = 40) and placebo (n = 40) groups...
Australian & New Zealand Journal of Psychiatry
March 4, 2022
Suresh Muthukumaraswamy, Anna Forsyth, Rachael Sumner
59 citations
With the extensive public, commercial and scientific interest from what has been widely termed the psychedelic renaissance, it is important that the scientific practices and results obtained from its implementation into medicine are put under a critical microscope. While there are numerous works on the potential benefits and applications of psychedelics as medicines, relatively little has been...
Expert Review of Clinical Pharmacology
May 26, 2021
Suresh Muthukumaraswamy, Anna Forsyth, Thomas Lumley
312 citations
Introduction: There is increasing interest in the potential for psychedelic drugs such as psilocybin, LSD and ketamine to treat several mental health disorders, with a growing number of randomized controlled trials (RCTs) being conducted to investigate the therapeutic effectiveness of psychedelics.Areas covered: We review previous literature on expectancy effects and blinding in the context of...
March 8, 2021
Suresh Muthukumaraswamy, Anna Forsyth, Thomas Lumley
16 citations
preprint
There is increasing interest in the potential for psychedelic drugs such as psilocybin, LSD and ketamine to treat a number of mental health disorders. To gain evidence for the therapeutic effectiveness of psychedelics, a number of randomised controlled trials (RCTs) have been conducted using the traditional RCT framework and these trials have generally shown promising results, with large effect...
Human Brain Mapping
December 6, 2019
Anna Forsyth, Rebecca McMillan, Doug Campbell et al.
19 citations
The pharmacological modulation of functional connectivity in the brain may underlie therapeutic efficacy for several neurological and psychiatric disorders. Functional magnetic resonance imaging (fMRI) provides a noninvasive method of assessing this modulation, however, the indirect nature of the blood-oxygen level dependent signal restricts the discrimination of neural from physiological...
Human Brain Mapping
October 21, 2019
Bhim M. Adhikari, Juergen Dukart, Joerg F. Hipp et al.
24 citations
Abstract Subanesthetic administration of ketamine is a pharmacological model to elicit positive and negative symptoms of psychosis in healthy volunteers. We used resting‐state pharmacological functional MRI (rsPhfMRI) to identify cerebral networks affected by ketamine and compared them to the functional connectivity (FC) in schizophrenia. Ketamine can produce sedation and we contrasted its...
Journal of Psychopharmacology
January 21, 2019
Rebecca McMillan, Anna Forsyth, Doug Campbell et al.
23 citations
BACKGROUND: Pharmacological magnetic resonance imaging has been used to investigate the neural effects of subanaesthetic ketamine in healthy volunteers. However, the effect of ketamine has been modelled with a single time course and without consideration of physiological noise. AIMS: This study aimed to investigate ketamine-induced alterations in resting neural activity using conventional...