circular insanity
circular psychosis

"There's a term for it in psychology that's called circular insanity," he said.

In 1851 he published an article describing a condition he called la folie circulaire (circular insanity), of which a patient would experience cycles of manic excitement and cycles of depression.

Two weeks later, on February 14, 1854, Jean-Pierre Falret presented a description to the Academy on what was essentially the same disorder, and designated folie circulaire ("circular insanity") by him.