Researchers gave eight patients with body dysmorphic disorder (an excessive preoccupation with appearance flaws) a single dose of psilocybin and measured their brain activity before and after treatment. They found that psilocybin increased communication between key brain regions involved in decision-making and attention control. Patients whose brains showed these changes experienced significant symptom improvement within a week, suggesting psilocybin may help by enhancing mental flexibility and emotional regulation in BDD.