Journal of Affective Disorders
February 12, 2026
Erica Kaczmarek, Nelson Rodriguez, Noah Chisamore et al.
Anhedonia, a core symptom of depression, is often resistant to conventional treatments and significantly impacts quality of life. This secondary analysis aimed to evaluate the effects of psilocybin-assisted psychotherapy (PAP) on anhedonia severity in individuals with treatment-resistant depression (TRD). Participants (n = 30) with TRD and a primary diagnosis of Major Depressive Disorder or...
Progress in Neuro-psychopharmacology and Biological Psychiatry
November 22, 2025
Shakila Meshkat, Noah Chisamore, Zoe Doyle et al.
PAP was associated with modest, short-term improvements in performance on measures of processing speed and executive function among individuals with TRD. While these changes appeared independent of mood, they did not consistently exceed expected practice effects. These findings highlight the need for adequately powered, controlled trials to clarify whether observed cognitive changes reflect...
Journal of Psychopharmacology
July 1, 2025
Ryan M Brudner, Erica Kaczmarek, Marc G Blainey et al.
3 citations
Background: Psilocybin-assisted psychotherapy (PAP) is a promising treatment for various psychiatric disorders. However, the exact biological and psychological mechanisms of action of PAP remain to be determined. Examining predictors of PAP outcomes may help identify necessary processes for positive treatment outcomes. Mystical experiences are considered a key aspect of the subjective effects...
The Canadian Journal of Psychiatry
March 25, 2025
Noah Chisamore, Erica Kaczmarek, Zoe Doyle et al.
1 citation
Objective: To compare changes in depression, anxiety, and suicidality symptoms after a single 25 mg oral dose of psilocybin between treatment-resistant depression participants not on antidepressants at screening to participants that discontinued antidepressant medications leading up to receiving psilocybin-assisted psychotherapy (PAP). Methods: Participants (n = 27) received at least one 25 mg...
Psychedelic Medicine
November 18, 2024
Shakila Meshkat, Erica Kaczmarek, Zoe Doyle et al.
8 citations
Background: Bipolar II disorder (BD-II) is often associated with chronic and treatment resistant major depressive episodes. Psilocybin has shown promise for its rapid-acting antidepressant effects, though its impact on bipolar depression remains unexplored. In the present subgroup analysis of an already published trial on treatment-resistant depression (TRD), we aimed to preliminarily evaluate...
Med (New York, N.Y.)
March 8, 2024
Joshua D. Rosenblat, Shakila Meshkat, Zoe Doyle et al.
97 citations
Psilocybin-assisted psychotherapy (PAP) has been associated with antidepressant effects. Trials to date have typically excluded participants with complex presentations. Our aim was to determine the feasibility of PAP in a complex population, including high levels of treatment resistance in major depressive and bipolar disorder and patients with baseline suicidality and significant comorbidity....