These rules revise our regulations for evaluating mental impairments. They also change some of the provisions of our Listing of Impairments (the Listings) that we use to evaluate mental disorders in adults. We also are adding guidance to the adult neurological listings regarding the evaluation of traumatic brain injury. In addition, the rules make technical changes to the adult digestive listings and the childhood mental disorders listings. We expect that these rules will clarify the intent and purpose of the listings for evaluating mental disorders, and will simplify our adjudication of claims involving mental impairments. These rules also recognize the sometimes unpredictable course of traumatic brain injury, and will improve our adjudication of claims involving traumatic brain injuries.