Bipolar Depression or as it is more commonly called Bipolar Disorder is a mood disorder. This means that many causes or symptoms can lead to Bipolar Depression.Bipolar Depression sufferers will experience bouts of serious depression and high mania. The disordered moods occur in cyclic patterns. There are mood swings from an extremely high or euphoric mood with some irritation mixed in to being extremely sad and hopeless. Between these two poles of mood swings, the individual will feel completely normal. They will not show any signs that they are suffering from erratic moods.