Abstract.In 2014, a 26-year-old male was involved in a motor vehicle accident resultingin a severe traumatic brain injury (TBI). The patient sustained a closed-headleft temporal injury with coup contrecoup impact to the frontal region. Thepatient underwent a left side craniotomy and was comatose for 26 days. Aftergaining consciousness, he was discharged to a brain injury treatment centerthat worked with physical, speech, and occupational issues. He was dischargedafter eight months with significant speech, ambulation, spasticity, andcognitive issues as well as the onset of posttraumatic epilepsy. His parentssought hyperbaric oxygen treatment (HBOT) from a doctor in Louisiana. After 165dives, the HBOT doctor recommended an addition of neurofeedback (NFB) therapy.In March 2019 the patient started NFB therapy intermixed with HBOT. Thecombination of NFB and HBOT improved plasticity and functionality in the areasof injury and the correlated symptoms including short-term memory, personality,language, and executive function, as well as significantly reducing theincidence of seizures. Severe brain injuries often leave lasting deficits withlittle hope for major recovery and there is a need for further research intolong-term, effective neurological treatments for severe brain injuries. Theseresults suggest that HBOT combined with NFB may be a viable option in treatingsevere brain injuries and should be investigated.