Researchers tested whether psilocybin, a psychedelic compound from magic mushrooms, could help reduce compulsive eating in rats bred to binge eat high-fat, high-sugar foods. Using a fear-conditioning experiment, they found that a single dose of psilocybin did not reduce the rats’ compulsive eating behavior at the dosage tested. However, the treatment may have affected fear-related freezing responses, suggesting psilocybin might influence brain circuits involved in learning and memory.