Alien Hand Syndrome to the rescue! The muse is pre-SMA
“Changes in the pre-SMA and its frontal connections can therefore affect both the objective capacity for voluntary control of action, and the subjective experience of agency.”
[The sense of a ‘muse’ taking over while playing the piano and ‘in the zone’ always seemed to me to be likely a ‘nice’ version of the experience of alien hand syndrome, and that they two might be governed by the same neural correlate. And the answer is yes-indeed!
The medial frontal-prefrontal network for altered awareness and control of action in corticobasal syndrome