I have encountered a lot of musicians who had never had the opportunity to play music that wasn't predetermined in a score. That is, they had only recited music from a score and had not had the opportunity to respond spontaneously or autonomously to musical collaborators.

When musicians enter MT training with a habitus like this, they have limited access to the musical observation skills required to pick up on clients' musical cues. They also have limited access to respond to those cues when they do pick them up.

Depending on their musical habitus, music therapists and MT students tend to sit somewhere towards the rigid end of the following spectrum from rigid to plastic.

Insular - (musically) unaware of others, unable to musically match others

Reactive - aware of someone else, react by reflex, unable to match

Yield - giving way, allowing others to their thing, developing capacity to match

Responsive - aware of others, able to respond spontaneously and appropriately to clients' musical cues

Mutual - able to to dialogue musically with client, able to discern when to hold firm and when to adjust musically to client with therapeutic intent.