The conceptual history of attention deficit hyperactivity disorder: idiocy, imbecility, encephalitis and the child deviant, 1877-1929

This article examines the medical discourse that formed the foundations of what mental health professionals today call Attention Deficit Hyperactivity Disorder (ADHD). The article examines literature from two medical discussions: 1)the discussion of "imbecility" and "idiocy" in the late 19th and early 20th centuries in Western Europe and in the United States; and 2) the diagnosis of encephalitis lethargica in children during the 1920s. The diagnosis of encephalitis lethargica was heavily influenced by the previous discussion of imbecility and occupied a seminal place in the history of medicalizing child behavior. It served as a specific disease category for kids who demonstrated unconventional behavior in a variety of social contexts. It will be argued that the discussion of encephalitis lethargica began a research modality in psychiatry which sought to find neurological bases for childhood deviance, typified by the contemporary discussion of ADHD.