What are the aetiology of manic depressive psychosis?

The exact cause of bipolar disorder, formerly known as manic depressive psychosis, is unknown. However, several factors may be involved, such as biological differences, genetics, and environmental triggers. People with bipolar disorder appear to have physical changes in their brains. The significance of these changes is still uncertain but may eventually help pinpoint causes. Bipolar disorder also seems to run in families, suggesting a genetic link. However, no single gene is responsible for bipolar disorder; instead, a number of genetic and environmental factors are thought to act as triggers. Stressful life events such as the breakdown of a relationship, physical, sexual, or emotional abuse, or the death of a close family member or loved one can trigger the symptoms of bipolar disorder.