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Matthew B. Wall

University College London, Imperial College London

40 papers in the library · 2,976 citations · publishing 2013-2026

Papers

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Human brain changes after first psilocybin use.

Nature Communications May 5, 2026 T Lyons, M Spriggs, L Kerkelä et al. 19 citations

Psychedelics have robust effects on acute brain function and long-term behavior but whether they also cause enduring functional and anatomical brain changes is largely unknown. In an exploratory, placebo-controlled, within-subjects, electroencephalography (EEG), and magnetic resonance imaging (MRI) study in 28 healthy, entirely psychedelic-naive participants, anatomical and functional brain...

Detecting neuroplastic effects induced by ketamine in healthy human subjects: A multimodal approach.

Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism March 21, 2026 Claudio Agnorelli, Joseph Peill, Gabriela Sawicka et al.

We investigated ketamine's neuroplastic effects in healthy human subjects using integrated Positron Emission Tomography (PET)/Magnetic Resonance Imaging (MRI) measures before and 1-8 days after a single psychedelic dose of ketamine (1 mg/kg, intravenous). Eleven male participants underwent two PET/MRI scans with [11C]-UCBJ (synaptic density/plasticity), 1H-MRS (glutamate and GABA) and...

Dissociable effects of LSD and MDMA on striato-cortical connectivity in healthy subjects.

Neuropsychopharmacology October 31, 2025 Natalie Ertl, Imran Ashraf, Lisa Azizi et al. 1 citation

Lysergic acid diethylamide (LSD) and 3,4-Methylenedioxymethamphetamine (MDMA) are widely used psychoactive drugs and their potential use in psychiatric medicine is currently generating interest. The mechanism by which these drugs may assist recovery in various disorders such as addiction and post-traumatic stress disorder (PTSD) is still not well understood. Most investigations of the effects...

Correction: Dissociable effects of psilocybin and escitalopram for depression on processing of musical surprises.

Mol Psychiatry July 1, 2025 Rebecca Harding, Neomi Singer, Matthew B. Wall et al. correction

The following part of the abstract had a minor error: ‘Following PT, there was greater activation in the ventromedial prefrontal cortex and sensory regions, and reduced activation in the angular gyrus.’ This is now corrected to ‘Following PT, there was decreased activation in the ventromedial prefrontal cortex and angular gyrus, and greater activation in sensory regions.’ The original article...

Receptor-enriched analysis of functional connectivity (REACT) for understanding cannabinoid neuropsychopharmacology

bioRxiv (Cold Spring Harbor Laboratory) June 5, 2025 Ekaterina Shatalina, Natalie Ertl, Kat Petrilli et al. 1 citation preprint

Abstract Background Cannabis is one of the most widely used psychoactive substances in the world and is increasingly investigated as a treatment for neuropsychiatric conditions. Cannabis contains delta-9-tetrahydrocannabinol (THC), which is thought to underlie its main psychoactive effects, and cannabidiol (CBD), which has been proposed to modulate the effects of THC on the brain. Both have...

Reduced Brain Responsiveness to Emotional Stimuli With Escitalopram But Not Psilocybin Therapy for Depression

American Journal of Psychiatry May 7, 2025 Matthew B. Wall, Lysia Demetriou, Bruna Giribaldi et al. 16 citations

Despite large improvements in depressive symptoms in the psilocybin group, psilocybin therapy had only a minor effect on brain responsiveness to emotional stimuli. These results are consistent with prior findings that the antidepressant action of SSRIs is often accompanied by a reduction in emotional responsiveness, but this effect may not occur in psychedelic therapy.

Dissociable effects of psilocybin and escitalopram for depression on processing of musical surprises

Molecular Psychiatry April 26, 2025 Rebecca Harding, Neomi Singer, Talma Hendler et al. 4 citations

Abstract Psilocybin therapy (PT) is emerging as an effective intervention for Major Depressive Disorder (MDD), offering comparable efficacy to conventional treatments like selective serotonin reuptake inhibitors (SSRIs). Music, an emotionally evocative stimulus, provides a valuable tool to explore changes in hedonic and predictive processing mechanisms via expectancy violations, or ‘surprises’....

THE EFFECTS OF ACUTE CANNABIS WITH AND WITHOUT CANNABIDIOL ON NEURAL REWARD ANTICIPATION IN ADULTS AND ADOLESCENTS

The International Journal of Neuropsychopharmacology February 1, 2025 Martine Skumlien, Tom P. Freeman, Daniel L. Hall et al.

Abstract Background Cannabis, and its main psychoactive compound tetrahydrocannabinol (THC), may alter the brain’ s reward system both acutely and over time. The endocannabinoid and reward systems mature during adolescence and adolescents may therefore respond differently to acute cannabis exposure compared with adults. Despite this, no previous functional magnetic resonance imaging (fMRI)...

Human neuroimaging: fMRI.

International review of neurobiology 2025 Matthew B. Wall, Robin Carhart-Harris

Human neuroimaging with functional Magnetic Resonance Imaging has been a key feature of the current wave of psychedelic research, in both healthy and clinical populations. The available data has suggested that classic psychedelics (psilocybin, LSD, DMT) have a characteristic effect of acutely and profoundly disrupting the normal pattern of resting-state connectivity in the human brain, and that...

High hopes? Precision psychedelic addiction medicine.

Frontiers in Psychiatry 2025 Rayyan Raja Zafar, Patrick Kleine, Danielle Kurtin et al.

Despite decades of neuroscience research and significant investment in addiction neuroimaging, clinical outcomes for individuals with substance use and behavioural addictions remain poor. Only 1.8% of people with substance use disorders receive effective treatment, highlighting a major disconnect between mechanistic understanding and clinical utility. This paper calls for a reorientation of...

Neuroimaging and the Investigation of Drug-Drug Interactions Involving Psychedelics.

Neurosci Insights October 8, 2024 Matthew B. Wall, Rebecca Harding, Natalie Ertl et al. 3 citations

Psychedelic therapies are an emerging class of treatments in psychiatry with great potential, however relatively little is known about their interactions with other commonly used psychiatric medications. As psychedelic therapies become more widespread and move closer to the clinic, they likely will need to be integrated into existing treatment models which may include one or more traditional...

Acute effects of different types of cannabis on young adult and adolescent resting-state brain networks

Neuropsychopharmacology May 28, 2024 Natalie Ertl, Tom P. Freeman, Claire Mokrysz et al. 19 citations

Adolescence is a time of rapid neurodevelopment and the endocannabinoid system is particularly prone to change during this time. Cannabis is a commonly used drug with a particularly high prevalence of use among adolescents. The two predominant phytocannabinoids are Delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD), which affect the endocannabinoid system. It is unknown whether this...

Scanning the new frontier of mental health: psychedelic brain imaging

The Biochemist March 14, 2024 Natalie Ertl, Matthew B. Wall

The use of psychoactive substances for ritual, spiritual and medicinal purposes stretches back into prehistory and has been a common feature of many diverse cultures and societies globally. Psychedelics, with their unique ability to amplify feelings of connectedness and openness, may have also served as tools for promoting tribal cohesion and trust in ancient cultures. Psychedelic is a broad...

The acute effects of cannabis, with and without cannabidiol, on attentional bias to cannabis related cues: a randomised, double-blind, placebo-controlled, cross-over study

Psychopharmacology February 28, 2024 Daniel L. Hall, Will Lawn, Shelan Ofori et al. 5 citations

RATIONALE: Attentional bias to drug-related stimuli is hypothesised to contribute towards addiction. However, the acute effects of Δ9-tetrahydrocannabinol (THC) on attentional bias to cannabis cues, the differential response in adults and adolescents, and the moderating effect of cannabidiol (CBD) are unknown. OBJECTIVES: Our study investigated (1) the acute effects of vaporised cannabis on...

Neuroimaging in psychedelic drug development: past, present, and future.

Molecular Psychiatry September 1, 2023 Matthew B. Wall, Rebecca Harding, Rayyan Zafar et al. 39 citations

Psychedelic therapy (PT) is an emerging paradigm with great transdiagnostic potential for treating psychiatric disorders, including depression, addiction, post-traumatic stress disorder, and potentially others. 'Classic' serotonergic psychedelics, such as psilocybin and lysergic acid diethylamide (LSD), which have a key locus of action at the 5-HT2A receptor, form the main focus of this...

Acute effects of Δ9-tetrahydrocannabinol (THC) on resting state connectivity networks and impact of COMT genotype: A multi-site pharmacological fMRI study

Drug and Alcohol Dependence August 11, 2023 Teuntje A. D. Pelgrim, Johannes G. Ramaekers, Matthew B. Wall et al. 3 citations

BACKGROUND: Cannabis produces various acute psychotropic effects, with marked individual differences. Cannabis use is a risk factor for developing psychotic disorders. The main component responsible for these effects is Δ9-tetrahydrocannabinol (THC). Here we investigated the neural basis of acute THC effects and its modulation by catechol-methyl-transferase (COMT) Val158Met genotype. METHODS:...

Associations between regular cannabis use and brain resting-state functional connectivity in adolescents and adults

Journal of Psychopharmacology July 29, 2023 Natalie Ertl, Will Lawn, Claire Mokrysz et al. 17 citations

BACKGROUND/AIM: Cannabis use is highly prevalent in adolescents; however, little is known about its effects on adolescent brain function. METHOD: = 70, 35 adolescents/35 adults). Pre-registered analyses examined the connectivity of seven major cortical and sub-cortical brain networks (default mode network, executive control network (ECN), salience network, hippocampal network and three striatal...

Increased low-frequency brain responses to music after psilocybin therapy for depression.

Journal of Affective Disorders July 15, 2023 Matthew B. Wall, Cynthia Lam, Natalie Ertl et al. 36 citations

Psychedelic-assisted psychotherapy with psilocybin is an emerging therapy with great promise for depression, and modern psychedelic therapy (PT) methods incorporate music as a key element. Music is an effective emotional/hedonic stimulus that could also be useful in assessing changes in emotional responsiveness following PT. Brain responses to music were assessed before and after PT using...

Psychedelic therapy in the treatment of addiction: the past, present and future

Frontiers in Psychiatry June 12, 2023 Rayyan Zafar, Maxim Siegel, Rebecca Harding et al. 95 citations

Psychedelic therapy has witnessed a resurgence in interest in the last decade from the scientific and medical communities with evidence now building for its safety and efficacy in treating a range of psychiatric disorders including addiction. In this review we will chart the research investigating the role of these interventions in individuals with addiction beginning with an overview of the...

The acute effects of cannabis with and without cannabidiol in adults and adolescents: A randomised, double‐blind, placebo‐controlled, crossover experiment

Addiction February 8, 2023 Will Lawn, Katie Trinci, Claire Mokrysz et al. 36 citations

Abstract Background and Aims Long‐term harms of cannabis may be exacerbated in adolescence, but little is known about the acute effects of cannabis in adolescents. We aimed to (i) compare the acute effects of cannabis in adolescent and adult cannabis users and (ii) determine if cannabidiol (CBD) acutely modulates the effects of delta‐9‐tetrahydocannabinol (THC). Design Randomised, double‐blind,...

Changes in music-evoked emotion and ventral striatal functional connectivity after psilocybin therapy for depression

Journal of Psychopharmacology November 26, 2022 Melissa Shukuroglou, Leor Roseman, David Nutt et al. 38 citations

Background: Music listening is a staple and valued component of psychedelic therapy, and previous work has shown that psychedelics can acutely enhance music-evoked emotion. Aims: The present study sought to examine subjective responses to music before and after psilocybin therapy for treatment-resistant depression, while functional magnetic resonance imaging (fMRI) data was acquired. Methods:...

Individual and combined effects of cannabidiol and Δ 9 -tetrahydrocannabinol on striato-cortical connectivity in the human brain

Journal of Psychopharmacology May 20, 2022 Matthew B. Wall, Tom P. Freeman, Chandni Hindocha et al. 21 citations

Background: Cannabidiol (CBD) and Δ 9 -tetrahydrocannabinol (THC) are the two major constituents of cannabis with contrasting mechanisms of action. THC is the major psychoactive, addiction-promoting, and psychotomimetic compound, while CBD may have opposite effects. The brain effects of these drugs alone and in combination are poorly understood. In particular, the striatum is implicated in the...

Increased global integration in the brain after psilocybin therapy for depression.

Nat Med April 11, 2022 Richard E. Daws, Christopher Timmermann, Bruna Giribaldi et al. 432 citations

Psilocybin therapy shows antidepressant potential, but its therapeutic actions are not well understood. We assessed the subacute impact of psilocybin on brain function in two clinical trials of depression. The first was an open-label trial of orally administered psilocybin (10 mg and 25 mg, 7 d apart) in patients with treatment-resistant depression. Functional magnetic resonance imaging (fMRI)...

Decreased brain modularity after psilocybin therapy for depression.

Research Square May 20, 2021 Richard E. Daws, Christopher Timmerman, Bruna Giribaldi et al. 11 citations

Abstract Importance Psilocybin therapy shows antidepressant potential; our data link its antidepressant effects to decreased brain network modularity post-treatment. Objective To assess the sub-acute impact of psilocybin on brain activity in patients with depression. Design Pre vs post-treatment resting-state functional MRI (fMRI) was recorded in two trials: 1) Open-label treatment-resistant...

Individual and combined effects of Cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) on striato-cortical connectivity in the human brain

bioRxiv (Cold Spring Harbor Laboratory) November 21, 2020 Matthew B. Wall, Tom P. Freeman, Chandni Hindocha et al. 4 citations preprint

Abstract Cannabidiol (CBD) and Δ9-tetrahydrocannabinol (THC) are two major constituents of cannabis with contrasting mechanisms of action. THC is the major psychoactive, addiction-promoting, and psychotomimetic compound, while CBD may have somewhat opposite effects. The brain effects of these drugs alone and in combination are poorly understood. In particular the striatum is implicated in the...