A large survey of randomly selected adults, sponsored by the National Institute of Mental Health (NIMH) and conducted between 2001 and 2003, found that an astonishing 46 percent met criteria established by the American Psychiatric Association (APA) for having had at least one mental illness within four broad categories at some time in their lives. The categories were “anxiety disorders,” including, among other subcategories, phobias and post-traumatic stress disorder (PTSD); “mood disorders,” including major depression and bipolar disorders; “impulse-control disorders,” including various behavioral problems and attention-deficit/hyperactivity disorder (ADHD); and “substance use disorders,” including alcohol and drug abuse. Most met criteria for more than one diagnosis. Of a subgroup affected within the previous year, a third were under treatment—up from a fifth in a similar survey ten years earlier.
Nowadays treatment by medical doctors nearly always means psychoactive drugs, that is, drugs that affect the mental state. In fact, most psychiatrists treat only with drugs, and refer patients to psychologists or social workers if they believe psychotherapy is also warranted. The shift from “talk therapy” to drugs as the dominant mode of treatment coincides with the emergence over the past four decades of the theory that mental illness is caused primarily by chemical imbalances in the brain that can be corrected by specific drugs.