The study aims to uncover the neural mechanisms by which psilocybin-assisted therapy affects obsessive-compulsive disorder (OCD) and whether those brain changes align with improvements in cognitive symptoms. A secondary goal is to test whether a low, tolerable dose is both practical and effective as a clinical treatment. The results will provide essential data for designing a future randomized controlled trial.
A case series of 12 patients with treatment-resistant depression treated with a novel protocol combining ketamine injections (0.5-1.5 mg/kg intramuscularly, 5-8 sessions) and brief psychodynamic psychotherapy found that 67% responded and 58% achieved remission. Half of the patients maintained remission at 3-month and 1-year follow-ups. Ego dissolution during the third ketamine session correlated with symptom improvement and psychological insight. The results suggest that combining ketamine with psychotherapy may enhance and prolong antidepressant effects beyond ketamine alone.
A protocol describes a planned study testing whether a low-moderate dose of psilocybin (10 mg), combined with non-interventional therapy, can improve cognitive flexibility and neuroplasticity in people with obsessive-compulsive disorder (OCD). Twenty blinded participants will receive an active placebo (1 mg psilocybin) in a first session and 10 mg in a second session four weeks later. Cognitive flexibility will be measured with the intradimensional-extradimensional shift task two days after each session, and neuroplasticity will be assessed via electroencephalography immediately after each session. Secondary outcomes include OCD symptom severity and patient-reported measures. The results are expected to clarify neural mechanisms and guide a future randomized controlled trial.