Cyclothymia is a rare mood disorder. This causes emotional ups and downs, but they are not as extreme as those in bipolar disorder. With ciclothymia, you will experience periods when your mood will change considerably from very good to very bad from the baseline. You may feel at the top of the world for a while, after which it will take a short while to feel somewhat on the ground. Between these maximum and minimum cyclotomics, you can feel good and set.