Mental disorders like depression, bipolar disorder, or schizophrenia were due to faulty brain chemicals, and ultimately, faulty genes. This message was popularized by books like Nancy Andreasen’s 1985 The Broken Brain, Solomon Snyder’s 1986 Drugs and the Brain, and Jon Franklin’s 1987 Molecules of the Mind. The “chemical imbalance” metaphor still has a powerful grip on the professional and public imagination.