bipolar disorder
Bipolar disorder is when you have mood swings. Your mood could shift from very happy to depressed to angry. They do not happen very quickly, but are distinctively different from the other moods. These severe mood swings range from mania or hypomania to severe depression. The symptoms of these are so dangerous because they could potentially lead to injuring yourself.
How are scientists trying to cure it
The main thing now is to take therapy. Talking to people is the main thing now that needs to happen. Some pills to take is antidepressant efficacy. But people would mostly talk to a therapist about their feelings but there is a lot of pills to try to make you relax and feel better.