Anhedonia, the blunted responsiveness to previously rewarding stimuli, is a core symptom of several psychiatric disorders. Ketamine and psilocybin have shown promising evidence in ameliorating anhedonic symptoms in clinical trials. The Probabilistic Reward Task (PRT) was developed to objectively quantify reward responsiveness in clinical populations and laboratory animals. Here, the PRT was...
Communications BiologyApril 24, 2026Tatum Askey, Daniel Allen-Ross, Daniil Luzyanin et al.
Chronic pain states remain challenging to control with current drug therapies. Here, we demonstrate that a single dose of psilocybin produces a sustained anti-nociceptive effect in chronic neuropathic pain models in male and female mice, mediated primarily by 5-HT2A receptors. Critically, psilocybin significantly potentiates the analgesic efficacy of gabapentin, a standard-of-care treatment,...
Abstract Psilocybin, a serotonergic psychedelic, can produce rapid and enduring antidepressant effects in patients with major depressive disorder (MDD)[1, 2], yet the neural mechanisms underlying these effects remain unclear. Negative affective biases are an important neuropsychological mechanism central to the development and perpetuation of MDD[3]. Using a translational rodent model, we...
Abstract The serotonergic psychedelic, psilocybin, shows potential for rapid and sustained antidepressant effects but the underlying mechanisms remain unknown. Using a chronic interferon-alpha–induced rat model of depression, we show acute psilocybin (0.3 mg/kg) reverses impaired reward-induced biases within 24hrs, with effects enduring for at least 7 days. This suggests psilocybin can restore...
Serotonergic psychedelic drugs are under investigation as therapies for various psychiatric disorders, including major depression. Although serotonergic psychedelic drugs are 5-HT2A receptor agonists, some such agonists are not psychedelic, potentially due to differences in 5-HT2A receptor ligand bias or signalling efficacy. Here, we investigated 5-HT2A receptor signalling properties of...
Abstract Chronic pain states are challenging to control with current drug therapies. Here, we demonstrate that a single dose of psilocybin can produce a sustained anti-nociceptive effect in a mouse model of chronic neuropathic pain. Beyond this, the single dose of psilocybin caused a dramatic increase in the anti-nociceptive potential of gabapentin, a widely used treatment for neuropathic pain,...
ABSTRACT Background and Purpose Serotonergic psychedelic drugs are under renewed investigation for the potential treatment of several psychiatric disorders. While all serotonergic psychedelics have 5-HT 2A receptor activity, the explanation for why some 5-HT 2A receptor agonists are not psychedelic is unknown. To address this question, we investigated the 5-HT 2A receptor signalling bias and...
How rapid-acting antidepressants (RAADs), such as ketamine, induce immediate and sustained improvements in mood in patients with major depressive disorder (MDD) is poorly understood. A core feature of MDD is the prevalence of cognitive processing biases associated with negative affective states, and the alleviation of negative affective biases may be an index of response to drug treatment....