Music therapy is gaining acceptance, based in part on some new research:
"...recent findings from McGill University’s Neuropsychology department suggest that specific parts of the brain are activated when patients listen to music which they like. And when the nucleus accumbens and the caudate nucleus, which are part of the reward, motivation and emotion systems, get jazzed up, a person starts feeling better. These same circuits release powerful chemicals when someone falls in love, eats good food, does drugs or has sex."
Rorro, nicknamed the "Violin Doc" (despite the fact that she plays a viola) says that live music, played slowly on lower-pitched instruments, with no lyrics and with a steady beat, connects best with the people she is treating.
You can read more about this, and watch some videos of Rorro playing, here, thanks to New York's WNYC:
Music Therapy Helps Vets Control Symptoms of PTSD