Kathleen Conneally successfully quit smoking, after a decades-long habit, with the help of psilocybin. Conneally was a participant in a study at Johns Hopkins University looking at whether nicotine addiction could be treated by psilocybin, the active compound in magic mushrooms. In this short video, staff writer Olga Khazan speaks with Conneally about her experience and uncovers the science of how psychedelics work in the brain to make this possible.

We want to hear what you think about this article. Submit a letter to the editor or write to letters@theatlantic.com.