My best friend's son had a stroke when the kid was about 18. The tranditional therapies only worked about 30% improvement over two years. The kid was in to music and I was involved in his band as a sound engineer. Since he did not have anything to lose, we tried various ideas including visualization in a meditative state (the Delta State). At the time, I was teaching meditation separately in a yoga center. It took about 6 months to get about 95% recovery and another 6 months to 99%. That was about 1990. Today, he is married and gainfully employed doing great.
I know, a lot more today and I think, I can speed up the process using certain medicines to improve nerve cell growth in conjunction with therapy. I do not know the demand for such service...may be someday I could set up a center to do that.