Mary Cregan’s debut work of nonfiction, The Scar: A Personal History of Depression and Recovery, is likely shelved in the bookshop’s memoir section. And The Scar does present—with remarkable clarity, candor and narrative presence—the author’s own history with the illness; in particular, a descent into suicidal depression after the death of her newborn daughter, Anna, and the hospitalization and treatment, including electroshock therapy, medication and talk therapy, that followed. But this book is far more than a memoir: it is the result of decades of research on the medical history of the