A Biological Century

At the outset of the 19th century, mental illnesses were few in number, loosely defined, explained through many diverse and often competing theories, and treated by a wide variety of healers. As the century progressed, theological views faded as understandings coalesced around a medical model that understood mental disturbances as comparable to organic diseases. They were brain malfunctions that were often transmitted through hereditarian processes and that should be specified and distinguished from each other through their etiology, course, and outcome. The most seriously ill often entered mental institutions that were run by superintendents affiliated with the new medical specialty of psychiatry. The more numerous classes of nervous patients came to seek help from somatically oriented doctors. Although explanations of mental disturbances still encompassed both internal and external factors, the balance had tilted sharply toward the former.