Vestibular stimulation has been shown to be a very effective noninvasive treatment for major depression. Bipolar disorder is a mental illness that presents cyclic sequences of depressive and euphoric states. Depressive phases of bipolar disorder are difficult to treat and usually are resistant to actual available treatments. This study investigates the effectiveness of a particular technique of vestibular stimulation in a group of 120 bipolar type I and II patients. After randomization 60 of them will receive specific vestibular stimulation (experimental group) and 60 will receive a sham vestibular stimulation.The study will conducted in Vest Brain, Centro de Estudios Neurovestibulares, in Chile.