From Scientific American: “A commercial sponsored by Pfizer, the drug company that manufactures the antidepressant Zoloft, asserts, “While the cause [of depression] is unknown, depression may be related to an imbalance of natural chemicals between nerve cells in the brain. Prescription Zoloft works to correct this imbalance.” Using advertisements such as this one, pharmaceutical companies have widely promoted the idea that depression results from a chemical imbalance in the brain . . . In reality, however, depression cannot be boiled down to an excess or deficit of any particular chemical or even a suite of chemicals. ‘Chemical imbalance is sort of last-century thinking. It’s much more complicated than that.'”