psychiatry (səkī´ətrē, sī–), branch of medicine that concerns the diagnosis and treatment of mental, emotional, and behavioral disorders, including major depression, schizophrenia, and anxiety. Although the Greeks recognized the significance of emotions in mental disorders, medieval thought emphasized demonic influence. From the Middle Ages until the time of the French physician Philippe Pinel (1745–1826), who instituted humanitarian reforms in the care of the mentally ill, there was no organized attempt to study or treat mental abnormalities or to provide decent institutional conditions for the mentally ill. Such 19th-century reformers as Dorothea Dix fought for improved conditions in asylums. The early 20th cent. saw the organization of the mental hygiene movement, dedicated to the prevention of mental disease through guidance clinics and education. Scientists of the period sought underlying causes of mental and nervous disorders. The German psychiatrist Emil Kraepelin was the first to divide psychosis into the two general classifications of manic-depressive psychosis (see bipolar disorder) and schizophrenia. Gradually, some psychiatrists, led by Sigmund Freud, turned to the behavior and emotional history of the patient as clues to the nature of psychoneurosis and psychosis.
Today, a wide variety of treatment strategies are used in psychiatry, to combat many different psychological disorders. Psychiatry may involve physiological or psychological treatment, or a combination of the two. Physiological treatment generally involves the use of drugs influencing neurotransmitter functions in the brain, or electroconvulsive treatment (see electroconvulsive therapy). Psychiatrists are licensed physicians, specially trained to treat patients with mental disorders and to prescribe drugs. In recent years, psychological difficulties have lost much of the stigma they once had, and many people have sought psychiatric help who might have been reluctant to do so in the past.
See C. M. McGovern, Masters of Madness: Social Origins of the American Psychiatric Profession (1985); C. Thompson, ed., The Origins of Modern Psychiatry (1987); L. Robins and D. Regier, ed., Psychiatric Disorders in America (1991); R. Michaels, ed., Psychiatry (1992); H. Kaplan and B. Sadock, Comprehensive Textbook of Psychiatry (2 vol., rev. ed. 1993); T. M. Luhrmann, Of Two Minds: The Growing Disorder in American Psychiatry (2000).