There’s physical differences in the brain between professional musicians and ordinary people.
Over time, portions of the corpus collosum and right hemisphere change.
So much so, neuroscientists can spot a professional musician by inspecting an image of their brain.
Which is very helpful as the regime tries to enforce the ban on unauthorized music production.
“Let me see your brains,” orders a state neuroscientist to a group of teenagers sitting in a garage.
The teenagers claimed to be playing a Rock Band video game with controllers that look like musical instruments, but you can never tell.
Hail to the state!