The part about the cerebellum is interesting because there used to be evidence of cerebellar control over emotional states in people who didn't have bipolar......
Compared to the brains of people without bipolar disorder, the researchers found that the MRI signal was elevated in the cerebral white matter and the cerebellar region of patients affected by bipolar disorder. The elevated signal may be due to either a reduction in pH or a reduction in glucose concentration - both factors influenced by cell metabolism.
Spurred on by the finding, Johnson and Wemmie conducted an extensive search of the scientific literature on bipolar disorder and began to find pieces of evidence that suggested that the cerebellum may function abnormally in bipolar disorder and that lithium might potentially target the cerebellum and alter glucose levels in this brain region.