What is manic-depressive disorder?
Manic-depressive disorder is the former name for bipolar disorder.
Bipolar disorder is a serious brain disease that causes extreme shifts in mood, energy, and functioning. It affects approximately 2.3 million adult Americans-about 1.2 percent of the population.2 Men and women are equally likely to develop this disabling illness. The disorder typically emerges in adolescence or early adulthood, but in some cases appears in childhood.3 Cycles, or episodes, of depression, mania, or “mlxed” manic and depressive symptoms typically recur and may become more frequent, often disrupting work, school, family, and social life.
Scientists are learning about the possible causes of bipolar disorder through several kinds of studies. Most scientists now agree that there is no single cause for bipolar disorder—rather, many factors act together to produce the illness.
Because bipolar disorder tends to run in families, researchers have been searching for specific genes—the microscopic "building blocks" of DNA inside all cells that influence how the body and mind work and grow—passed down through generations that may increase a person's chance of developing the illness. But genes are not the whole story. Studies of identical twins, who share all the same genes, indicate that both genes and other factors play a role in bipolar disorder. If bipolar disorder were caused entirely by genes, then the identical twin of someone with the illness would always develop the illness, and research has shown that this is not the case. But if one twin has bipolar disorder, the other twin is more likely to develop the illness than is another sibling.
Manic-depressive disorder is the former name for bipolar disorder.
Scientists are learning about the possible causes of bipolar disorder through several kinds of studies. Most scientists now agree that there is no single cause for bipolar disorder—rather, many factors act together to produce the illness.
Because bipolar disorder tends to run in families, researchers have been searching for specific genes—the microscopic "building blocks" of DNA inside all cells that influence how the body and mind work and grow—passed down through generations that may increase a person's chance of developing the illness. But genes are not the whole story. Studies of identical twins, who share all the same genes, indicate that both genes and other factors play a role in bipolar disorder. If bipolar disorder were caused entirely by genes, then the identical twin of someone with the illness would always develop the illness, and research has shown that this is not the case. But if one twin has bipolar disorder, the other twin is more likely to develop the illness than is another sibling.