The purpose of this study is to discover the feasibility of conducting clinical research in individuals with chronic sequelae following brain injury who are given hyperbaric oxygen. This study will also look at the outcome of individuals with a chronic stable brain injury due to trauma, anoxia (lack of oxygen to the brain), or stroke, who are given hyperbaric oxygen. Outcome measures testing cognitive (memory, etc.) and functional (balance, strength, etc.) measures will be performed before the hyperbaric sessions, immediately following them, and 6 months later. The subject will receive 60 hyperbaric sessions, 60 minutes in the chamber, to a pressure of 1.5 ATA, once daily, Monday through Friday.