A teenage boy, who has no muscle movement that I had seen during music sessions, listens to the music and sounds but cannot physically engage that well. Recently, I walked around with my guitar allowing the students to strum the strings or to put their hand on the guitar (often with the teachers help) to feel the vibrations. From his wheel chair, the teacher moved his arm forward by pushing on his elbow and guiding his hand up to feel the vibrations. He continued to move his hand high all by himself and started moving his fingers, which played the strings. We did this for a few minutes and he was directly engaged in the music and moving his muscles.
This showed us all that through trying different approaches, each person has the ability to play, engage, interact and enjoy music.