Bipolar Disorder (BD) is a complex mental health condition marked by extreme shifts in mood, energy, activity levels, and concentration. These shifts involve distinct periods of elevated or irritable mood, known as manic or hypomanic episodes, and periods of significant low mood, or depressive episodes. Tracing the history of this condition reveals a long journey from ancient observations of extreme emotional states to the sophisticated diagnostic criteria used by clinicians today. The recognition of BD as a single, cyclical illness, distinct from other forms of mental distress, is a story of gradual scientific discovery.
Early Observations of Mood Cycles
The recognition of extreme mood states dates back to ancient Greek and Roman medical thought, though these symptoms were not yet understood as a unified disorder. Hippocrates, often called the father of medicine, was the first to systematically document two distinct mood extremes: melancholia and mania. He and later physician Galen explained these states through the theory of humoral pathology, suggesting health depended on the balance of four bodily fluids.
Melancholia (intense sadness and fear) was attributed to an excess of black bile, while mania (agitation and excitement) was linked to an excess of yellow bile. For many centuries, melancholia and mania were largely considered separate illnesses. However, the physician Aretaeus of Cappadocia, in the first century, suggested a connection, proposing that both conditions existed on a continuous spectrum and could be manifestations of a single, brain-related disease.
Formal Identification in the 19th Century
The formal identification of what is now recognized as bipolar disorder began in mid-19th century France with the first scientific attempts to define its recurrent, cyclical nature. In 1854, the French psychiatrist Jean-Pierre Falret described folie circulaire, or “circular insanity,” to the French Imperial Academy of Medicine. Falret’s description defined the illness as a continuous cycle of depression, mania, and symptom-free intervals occurring in the same patient.
Two weeks prior to Falret’s presentation, a colleague, Jules Baillarger, presented a similar concept, describing folie à double forme, or “dual-form insanity.” Baillarger’s description detailed an illness characterized by a succession of manic and depressive episodes, though his initial description suggested a rapid shift without a symptom-free period, differentiating it from Falret’s folie circulaire. Despite a dispute over priority, the work of both French psychiatrists established the concept of a recurrent, cyclical affective disorder, paving the way for modern diagnosis.
Categorization of Manic-Depressive Illness
The concept of a cycling mood disorder was formalized and categorized by German psychiatrist Emil Kraepelin at the turn of the 20th century. Kraepelin synthesized the earlier French observations, creating the comprehensive category of “manic-depressive insanity” in the late 1800s. His work established a diagnostic framework that unified various mood presentations, including single episodes of mania or depression, under one classification.
Kraepelin’s most significant contribution was the clear differentiation of manic-depressive insanity from dementia praecox (now schizophrenia). He noted that manic-depressive illness had a course marked by episodes punctuated by periods of relative normalcy and a better long-term prognosis. In contrast, he viewed dementia praecox as a progressively deteriorating disease leading to cognitive decline. This distinction, based on the long-term course and outcome, became a foundational paradigm in psychiatric diagnosis.
Adopting the Term Bipolar Disorder
The condition was known as “manic-depressive illness” through the mid-20th century, appearing as “manic-depressive reaction” in the DSM-I (1952). The shift to modern terminology occurred with the publication of the DSM-III in 1980, where “manic-depressive illness” was formally replaced by “Bipolar Disorder.”
The new name, meaning “two poles,” accurately reflects the core feature of the disorder: the oscillation between the opposite mood states of mania/hypomania and depression. This change also helped reduce the historical stigma associated with the word “insanity” in the older name. The DSM-III began to solidify the modern spectrum approach by introducing criteria that distinguished between unipolar and bipolar depression, leading to the recognition of subtypes like Bipolar I and Bipolar II.