In a small open-label trial, 12 people with Parkinson’s disease received two doses of psilocybin (first 10 mg, then 25 mg) alongside psychotherapy. Participants reported reduced depression and anxiety, improved cognitive flexibility, and better motor function, with no serious side effects and the improvements lasted at least six weeks. Researchers had expected mood changes but were surprised by the physical benefits, which suggest psilocybin can help with the motor symptoms of neurological diseases.