We examined the effectiveness of neurotherapy for chronic, impaired self-awareness and secondary ADHD (SADHD) diagnosed in the patient after severe TBI. We hypothesized a good response to relative beta training. Patient A.A., age 30, after severe TBI and long-term coma, suffered from chronic, impaired self-awareness and SADHD, manifesting two years post trauma. Only slight progress was made after behavioral training. The patient took part in a neurotherapy program consisting of 40 sessions of relative beta training. We used standardized neuropsychological testing, as well as ERPs before and after the completion of neurotherapy. At baseline, A.A. showed an excess of relative mu-rhythm, possibly associated with ADHD (alpha subtype); decreased beta generated centrally, indicating hyperactivation of the central medial cortical area and possibly associated with anxiety; and a decreased visual-related component, an indicator of TBI. There was no significant improvement of the P300 NOGO component after the conclusion of the neurotherapy program. However, as hypothesized, she showed improvements in cognitive parameters, especially attention, memory and executive function, including remission of the impaired self-awareness and SADHD. The patient finished her studies and has now started working. A neurofeedback program using relative beta-theta training produced slight physiological changes in our TBI patient, but major cognitive and behavioral changes, including reduced impaired self-awareness and SADHD. ERPs can be used to assess SADHD and functional brain changes induced by neurotherapy, but has limited application for interpreting the brain mechanism of chronic, impaired self-awareness after severe TBI and long term coma.