Disclosed are the unique and unexpected findings that xenon gas possesses the ability to directly inhibited amyloid beta associated toxicity, inhibit production of amyloid beta, and stimulate synthesis of soluble, free-form amyloid beta. The invention teaches the use of xenon gas, as well as various combinations of Noble Gases, for the prevention, amelioration, and treatment of Alzheimer's Disease and other pathologies associated with generation of insoluble aggregates containing amyloid beta.