Fatal Familial Insomnia (FFI), is an autosomal dominate disease that is invariably fatal after about six to 30 months without sleep. FFI is probably misnamed because death results from multiple organ failure rather than sleep deprivation. The pathological processes include degeneration of the thalamus and other brain areas, over-activity of the sympathetic nervous system, hypertension, fever, tremors, stupor, weight loss, and disruption of the body's endocrine systems. FFI belongs to a class of infectious prion diseases that include Mad Cow Disease.