Bipolar disorder research papers point out that the disease affects nearly one percent of the United States population. It is a mood disorder involving degrees of mania as well as depression. It was previously known as Manic-Depression, but the title was misleading, as many people believed it was a form of depression. The name was changed to its current state to reflect that the moods of people who suffer from it fluctuate between the polar opposites of the mood spectrum. Patients are generally diagnosed with bipolar disorder, rather than depression, when they show telltale signs of mania.
A manic episode is an abnormally and persistently elevated, expansive, or irritable mood lasting for at least one week in adults. Other symptoms of mania include irritability, little sleep, excessive amounts of energy, unproductivity, racing thoughts, and being easily distracted. During depressive episodes, bipolar individuals can feel sad, lose interest in enjoyable activities, sleeping problems, loss of appetite, thoughts of suicide or death. The degree to which people display these symptoms, as well as the length of the cycles between the symptoms, determines the sub-category of bipolar disorder. Bipolar I disorder occurs when the person shows manic and depressive episodes, as well as mixed episodes. Bipolar II disorder occurs when the person displays mild mania (hypomania) and full depressive episodes. This is often misdiagnosed as depression. Another form of bipolar is schizo-affective disorder, where individuals have mania and depression, but also have persistent psychotic episodes.